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Flashcards in PAEDIATRICS Deck (140)
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1
Q

RETARDED SKELETAL MATURATION

Chronic ill-health

A
  1. Congenital heart disease—particularly cyanotic.
  2. Renal failure.
  3. Inflammatory bowel disease*.
  4. Malnutrition.
  5. Rickets*.
  6. Maternal deprivation.
2
Q

RETARDED SKELETAL MATURATION

Endocrine disorders

A
  1. Hypothyroidism—severe retardation (≥5 standard deviations
    below the mean) with granular, fragmented epiphyses.
  2. Steroid therapy/Cushing’s disease—see Part 2.
  3. Hypogonadism—including older patients with Turner syndrome.
  4. Hypopituitarism—panhypopituitarism, growth hormone deficiency
    and Laron dwarfism (insensitivity to growth hormone)
3
Q

RETARDED SKELETAL MATURATION

Congenital disorders

A
  1. Chromosome disorders—e.g. trisomy 21, trisomy 18 (severe),
    Turner syndrome.
  2. Skeletal dysplasias involving the epiphyses—e.g. multiple
    epiphyseal dysplasia, pseudoachondroplasia, diaphyseal dysplasia,
    metatropic dysplasia
4
Q

GENERALIZED ACCELERATED
SKELETAL MATURATION
Endocrine disorders

A
  1. Idiopathic precocious puberty.
  2. Hypothalamic dysfunction—e.g. due to mass lesions (hamartoma,
    astrocytoma, craniopharyngioma, optic chiasm glioma),
    hydrocephalus or encephalitis.
  3. Adrenal and gonadal tumours—e.g. androgen-producing
    neoplasms.
  4. Hyperthyroidism
5
Q

GENERALIZED ACCELERATED
SKELETAL MATURATION
Congenital disorders

A
  1. McCune-Albright syndrome—polyostotic fibrous dysplasia +
    precocious puberty.
  2. Cerebral gigantism (Sotos syndrome).
  3. Lipodystrophy.
  4. Pseudohypoparathyroidism*—premature fusion of cone-shaped
    epiphyses.
  5. Acrodysostosis—premature fusion of cone-shaped epiphyses
6
Q

GENERALIZED ACCELERATED
SKELETAL MATURATION
Others

A
  1. Large or obese children.

2. Familial tall stature.

7
Q

PREMATURE CLOSURE OF A

GROWTH PLATE

A
  1. Local hyperaemia—juvenile idiopathic arthritides, infection,
    haemophilia or arteriovenous malformation.
  2. Trauma—especially Salter-Harris fractures.
  3. Vascular occlusion—postmeningococcal septicaemia, infarcts and
    sickle cell anaemia.
  4. Radiotherapy.
  5. Thermal injury—burns, frostbite.
  6. Multiple exostoses or enchondromatosis.
  7. Hypervitaminosis A—now more commonly via vitamin A
    analogue treatment for dermatological conditions rather than
    dietary overdosage.
  8. Skeletal dysplasias—e.g. Albright’s hereditary osteodystrophy,
    acrodysostosis, acromesomelic dysplasia (Maroteaux type) and trichorhinophalangeal syndrome; all with premature fusion of
    cone-shaped epiphyses in the hand.
  9. Iatrogenic—for leg length discrepancies surgical epiphysiodesis
    can be performed to artificially fuse or slow the growth of a
    normal leg to allow the shorter leg to grow
8
Q

ASYMMETRICAL MATURATION

Hemihypertrophy or localized gigantism

A
  1. Vascular anomalies.
    (a) Parkes-Weber syndrome—fast-flow vascular malformations
    with arteriovenous shunting, port-wine stain and limb
    overgrowth.
    (b) Klippel-Trénaunay syndrome*—triad of anomalous veins
    (varicosities or slow-flow malformations), port-wine stain and
    limb overgrowth.
    (c) Capillary malformation (port-wine stain)—associated with
    congenital hypertrophy.
  2. Chronic hyperaemia—e.g. juvenile idiopathic arthritides and
    haemophilia.
  3. Hemihypertrophy—M>F; R>L. May be a presenting feature of
    Beckwith-Wiedemann syndrome (hemihypertrophy, macroglossia,
    hypoglycaemia and umbilical hernia). Increased risk of Wilms
    tumour.
  4. Neurofibromatosis* (NF1).
  5. Macrodystrophia lipomatosa—bony and fatty overgrowth of one
    or more digits.
  6. Russell-Silver dwarfism—evident from birth. Triangular face with
    down-turned corners of the mouth, frontal bossing, asymmetrical
    growth and skeletal maturation.
  7. Proteus syndrome—hamartomatous disorder with multiple and
    varied manifestations including vascular and lymphatic
    malformations, macrocephaly and cranial hyperostosis.
  8. WAGR syndrome—Wilms tumour, aniridia, genitourinary
    anomalies and mental retardation.
9
Q

ASYMMETRICAL MATURATION

Hemiatrophy or localized atrophy

A
  1. Paralysis—with osteopenia and overtubulation of long bones.
  2. Radiation treatment in childhood.
  3. Pure venous malformation involving skin, muscle and bone
10
Q

SKELETAL DYSPLASIAS

With predominant metaphyseal involvement

A
  1. Achondroplasia*—see Part 2. NB: hypochondroplasia is due to
    mutations in the same gene, fibroblast growth factor receptor 3,
    with milder features.
  2. Metaphyseal chondrodysplasias.
    (a) Jansen—severe rickets-like changes with short stature.
    (b) Schmid—milder than Jansen. Bowed legs.
    (c) McKusick—immune deficiency and haematological
    problems.
    (d) Shwachman-Diamond—with pancreatic insufficiency
    and neutropenia.
    (e) Hypophosphatasia—severe forms are lethal. V-shaped
    metaphyseal defects. Diaphyseal spurs.
    (f) Jeune’s asphyxiating thoracic dystrophy—short ribs with
    irregular costochondral junctions, renal cysts and short hands.
    (g) Ellis-van Creveld syndrome—short ribs with congenital heart
    disease and polydactyly.
11
Q

SKELETAL DYSPLASIAS
With predominant epiphyseal involvement
3

A
  1. Multiple epiphyseal dysplasia—irregular epiphyseal ossification.
    Epiphyses may be small and round or flat, depending on type.
    Normal metaphyses, mild spine changes, mild short stature.
  2. Pseudoachondroplasia—more severe epiphyseal dysplasia with short stature; proportions resemble achondroplasia but with a normal face. Spinal radiographic changes, but usually preserved spinal height.
  3. Diastrophic dysplasia—flattened epiphyses with joint contractures
    (e.g. club feet) and kyphoscoliosis. Cauliflower ear in infancy.
    Hypoplastic proximally placed ‘hitch-hiker’s’ thumb is characteristic
12
Q
SKELETAL DYSPLASIAS
Mesomelic dysplasias (short forearms ± shanks)
A
  1. Dyschondrosteosis (Leri-Weill)—short radius + Madelung
    deformity and dorsal subluxation of distal ulna.
  2. Langer mesomelic dysplasia—more severe mesomelic
    shortening.
  3. Acromesomelic dysplasia (Maroteaux type)—short upper limbs
    with shortening more severe from distal to proximal. Associated
    spinal abnormalities
13
Q
SKELETAL DYSPLASIAS
Acromelic dysplasias (short hands and feet) 4
A
  1. Pseudo- and pseudopseudo-hypoparathyroidism—metacarpal ±
    phalangeal shortening. Soft-tissue/basal ganglia calcifications and
    exostoses in some.
  2. Brachydactyly types A–E—abnormal hands and feet only.
  3. Acrodysostosis—very short metacarpals and phalanges with cone
    epiphyses. Similar to acromesomelic dysplasia on imaging.
  4. Trichorhinophalangeal syndrome—multiple short phalanges with
    cone epiphyses. Sparse hair and typical facial appearances. Type 2
    associated with exostoses
14
Q

SKELETAL DYSPLASIAS
Dysplasias with major involvement of the spine
2

A
  1. Type 2 collagen disorders
    includes spondyloepiphyseal dysplasia congenita, Kniest and Stickler type 1. Delayed appearance of epiphyseal ossification centres with progressive platyspondyly and spinal deformity. Associated ear and eye problems and micrognathia in many. Hands and feet near normal.
  2. Metatropic dysplasia—‘changing form’.
    In infancy manifests as short-limbed dysplasia, evolving into short spine dysplasia over childhood. Epiphyseal ossification delay with marked metaphyseal flare. Characteristic pattern of platyspondyly with wide flat
    vertebral bodies. Some patients have a tail. Spondylometaphyseal
    dysplasia (Kozlowski type) is a milder form.
15
Q

LETHAL NEONATAL DYSPLASIA

A
  1. Thanatophoric dysplasia—short ribs; severe platyspondyly with
    wafer-thin vertebral bodies; small square iliac wings; severe limb
    shortening. Curved femora and humeri (‘telephone handle’) in
    type 1; craniosynostosis in type 2.
  2. Osteogenesis imperfecta type 2—deficient skull ossification;
    numerous fractures resulting in crumpled long bones and
    beaded ribs.
  3. Achondrogenesis—absent or poor ossification, especially of
    vertebral bodies; small chest; very short long bones.
  4. Hypochondrogenesis—milder form of achondrogenesis, but still
    lethal.
  5. Short rib polydactyly syndromes—extremely short ribs;
    polydactyly in most with variable acromesomelic shortening
    depending on type.
  6. Fibrochondrogenesis—short long bones with metaphyseal flaring
    and diamond-shaped vertebrae.
  7. Campomelic dysplasia—bowed femora and tibiae. Deficient
    ossification of thoracic pedicles and severe hypoplasia of scapular
    blades are most characteristic features. Eleven ribs.
  8. Chondrodysplasia punctata—see Section 14.15.
  9. Lethal hypophosphatasia—severely deficient skull ossification.
    Absent pedicles in spine. Missing bones. Variable metaphyseal
    defects. Some bones look normal.
16
Q
CONDITIONS EXHIBITING
DYSOSTOSIS MULTIPLEX
dysostosis refers to abnormal 
bone formation in early pregnancy and the distribution of 
involved bones remains static
A

(a) Abnormal bone texture.
(b) Large skull vault with calvarial thickening.
(c) J-shaped sella + poor pneumatization of paranasal sinuses.
(d) Odontoid hypoplasia + atlantoaxial subluxation.
(e) Anterior beak of upper lumbar vertebrae + gibbus deformity.
(f) Inferior tapering of iliac bones + steep acetabula + coxa valga.
(g) Widened diaphyses, e.g. ribs (oar-shaped), clavicles, small
tubular bones.
(h) Tilting of distal radius and ulna towards each other.
(i) Pointing of the proximal ends of the metacarpals

17
Q

Diseases exhibiting dysostosis multiplex

rare disease of congenital origin characterized by chondrodystrophic skeletal changes and deposition of a lipid-like substance

6

A
  1. Mucopolysaccharidoses.
  2. Mucolipidoses types I–III.
  3. Fucosidosis types I and II.
  4. GM1 gangliosidosis.
  5. Mannosidosis.
  6. Aspartylglucosaminuria
Superiorly notched [inferiorly beaked] vertebral bodies
Middle beaked in MPS I
Posterior scalloping
Rounded iliac wings
Ilia, tapered inferiorly
Abnormal J-shaped sella
Thickened diploic space
Short, thick clavicles
Paddle [oar-shaped] ribs
Mildly hypoplastic epiphyses [often generalized]
 Long/narrow femoral neck
 Hypoplastic/fragmented CFE
Thick [short] diaphyses
Proximal humeral notching
Metacarpals: Proximal pointing
 Metacarpals: Thick, short, with thin cortices
 Carpal bones: Irregular, hypoplastic
 Tarsal bones: Irregular contours
18
Q

GENERALIZED INCREASED BONE DENSITY

Dysplasias

A
  1. Osteopetrosis—diffuse bony sclerosis due to reduced osteoclast
    activity, with a ‘bone-in-bone’ appearance and ‘rugger jersey’
    spine. Increase risk of fractures.
  2. Pyknodysostosis—short stature, hypoplastic lateral ends of
    clavicles, hypoplastic terminal phalanges, bulging cranium and
    delayed closure of the anterior fontanelle.
  3. Dysosteosclerosis—thought to be an osteoclast-poor form of
    osteopetrosis in infancy, but does not cause ‘bone-in-bone’
    appearance. Progressive spinal involvement with endplate
    irregularity, and marked undertubulation of long bones with
    submetaphyseal lucencies.
  4. Progressive diaphyseal dysplasia (Camurati-Engelmann
    syndrome)—diffuse symmetrical cortical thickening in diaphyses
    of long bones (especially femur and tibia) ± skull or spine
    involvement.
  5. Melorheostosis—undulating periosteal ± endosteal hyperostosis
    with a characteristic ‘dripping candle wax’ appearance. Involves
    one or more bones in a single limb, in a sclerotomal distribution.
  6. Wnt-pathway disorders—including endosteal hyperostosis,
    hyperostosis corticalis generalisata, sclerosteosis and osteopathia
    striata
19
Q

GENERALIZED INCREASED BONE DENSITY

Metabolic

A
  1. Renal osteodystrophy*—rarely renal osteodystrophy causes bone
    sclerosis, typically seen as a ‘rugger jersey’ spine. Oxalosis may also
    cause renal failure and bone sclerosis
20
Q

GENERALIZED INCREASED BONE DENSITY paediatrics
Poisoning
4

A
  1. Lead—dense metaphyseal bands. Cortex and flat bones may also
    be slightly dense. Modelling deformities later, e.g. flask-shaped femora.
  2. Fluorosis—more common in adults. Thickened cortex at the
    expense of the medulla. Periosteal reaction. Ossification of
    ligaments, tendons and interosseous membranes.
  3. Hypervitaminosis D—slightly increased density of skull and
    vertebrae early, followed later by osteoporosis. Soft-tissuecalcification. Dense metaphyseal bands and widened zone of provisional calcification.
  4. Chronic hypervitaminosis A—not <1 year of age. Cortical
    thickening of long and tubular bones, especially in the feet.
    Subperiosteal new bone. Normal epiphyses, reduced metaphyseal
    density. The mandible is not affected (cf. Caffey’s disease)
21
Q

GENERALIZED INCREASED BONE DENSITY

Idiopathic

A
  1. Caffey’s disease (infantile cortical hyperostosis)—see Section 14.11.
  2. Idiopathic hypercalcaemia of infancy—probably a manifestation
    of hypervitaminosis D. Generalized increased density or dense
    metaphyseal bands. Increased density of skull base.
22
Q

PAEDIATRIC TUMOURS THAT METASTASIZE TO BONE

A
  1. Neuroblastoma.
  2. Leukaemia.
  3. Lymphoma*.
  4. Renal clear cell sarcoma.
  5. Rhabdomyosarcoma.
  6. Retinoblastoma.
  7. Ewing sarcoma—lung metastases much more common.
  8. Osteosarcoma—lung metastases much more common
23
Q

‘MOTH-EATEN BONE’ IN A CHILD

Neoplastic

A
  1. Neuroblastoma metastases.
  2. Leukaemia—consider when there is diffuse involvement of an
    entire bone or a neighbouring bone with low T1 and high T2/STIR
    signal on MRI.
  3. Long bone sarcomas—Ewing sarcoma and osteosarcoma.
  4. Lymphoma of bone.
  5. Langerhans cell histiocytosis (LCH)*.
24
Q

‘MOTH-EATEN BONE’ IN A CHILD

Infective

A
  1. Acute osteomyelitis
25
Q

PERIOSTEAL REACTIONS—BILATERALLY

SYMMETRICAL IN CHILDREN

A
  1. Normal infants—diaphyseal, not extending to the growth plate,
    bilaterally symmetrical and a single lamina. Frequently involves
    femur, tibia and humerus. Very unusual >4 months of age. A
    mimicker of trauma; sometimes difficult to differentiate from child
    abuse when seen incidentally on skeletal survey.
  2. Juvenile idiopathic arthritis*—in ~25% of cases. Most common in
    the periarticular regions of phalanges, metacarpals and metatarsals.
    When it extends into the diaphysis it will eventually result in
    enlarged, rectangular tubular bones.
  3. Acute leukaemia—associated with prominent metaphyseal bone
    resorption ± a dense zone of provisional calcification. Osteopenia.
    Metastatic neuroblastoma can look identical.
  4. Rickets*—the presence of uncalcified subperiosteal osteoid mimics
    a periosteal reaction because the periosteum and ossified cortex
    are separated.
  5. Caffey’s disease—first evident <5 months of age. Mandible,
    clavicles and ribs show cortical hyperostosis and a diffuse periosteal
    reaction. The scapulae and tubular bones are affected less often
    and tend to be involved asymmetrically.
  6. Scurvy*—subperiosteal haemorrhage is most frequent in the
    femur, tibia and humerus. Periosteal reaction is particularly evident
    in the healing phase. Age ≥6 months.
  7. Prostaglandin E1 therapy—in infants with ductus-dependent
    congenital heart disease. Severity is related to duration of therapy.
    Other features include pseudowidening of cranial sutures and
    bone-in-bone appearance.
  8. Congenital syphilis*—an exuberant periosteal reaction can be due
    to infiltration by syphilitic granulation tissue (diaphyseal) or healing
    of osteochondritis by callus (metaphyseal-epiphyseal junction)
26
Q

SYNDROMES AND BONE DYSPLASIAS
FEATURING MULTIPLE FRACTURES
With reduced bone density

A
  1. Osteogenesis imperfecta.
  2. Rickets*—usually only in presence of severe rachitic change and
    clear demineralization.
  3. Hypophosphatasia.
  4. Juvenile idiopathic osteoporosis—2–4 years duration, age of
    onset 2–13 years.
  5. Gerodermia osteodysplastica—osteopenia and wormian bones
    associated with wrinkly skin (cutis laxa) and hip dislocation.
  6. Osteoporosis-pseudoglioma syndrome—blindness in infancy +
    bony fragility.
  7. Mucolipidosis II—osteopenia and periosteal ‘cloaking’ in infancy,
    evolving into dysostosis multiplex.
  8. Cushing’s syndrome.
27
Q

SYNDROMES AND BONE DYSPLASIAS
FEATURING MULTIPLE FRACTURES
With normal bone density
2

A
  1. Cleidocranial dysplasia( absent/hypoplastic clavicles; widened sutures, brachycephaly,, maxilla/max sinus hypoplasia, wormian bones, supernumery teeth).
  2. Fibrous dysplasia.
28
Q

SYNDROMES AND BONE DYSPLASIAS
FEATURING MULTIPLE FRACTURES
With increased bone density

A
  1. Osteopetrosis.

2. Pyknodysostosis

29
Q

PSEUDARTHROSIS IN A CHILD 7

A
  1. Nonunion of a fracture—including pathological fracture.
  2. Congenital—in the mid-lower third of the tibia ± fibula. 50%
    present in the first year. Later there may be cupping of the
    proximal bone end and pointing of the distal bone end.
  3. Neurofibromatosis*—identical to congenital tibial pseudarthrosis.
  4. Osteogenesis imperfecta.
  5. Cleidocranial dysplasia*—congenitally in the femur.
  6. Fibrous dysplasia.
  7. Proximal focal femoral deficiency—at the site of the femoral
    defect
30
Q

‘BONE WITHIN A BONE’ APPEARANCE 8

A
  1. Normal neonate—especially in the spine.
  2. Growth arrest/recovery lines.
  3. Bisphosphonate therapy—similar to growth arrest lines.
  4. Osteopetrosis.
  5. Sickle cell anaemia.
  6. Gaucher disease*.
  7. Heavy metal poisoning.
  8. Prostaglandin E1 therapy
31
Q

IRREGULAR OR STIPPLED EPIPHYSES 11

A
  1. Normal—particularly in the distal femur.
  2. Avascular necrosis—single, e.g. Perthes’ disease (although 10% are bilateral), or multiple, e.g. sickle cell anaemia.
  3. Congenital hypothyroidism—not present at birth. Delayed appearance and growth of ossification centres. Appearance varies from slightly granular to fragmentation. The femoral capital epiphysis may be divided into inner and outer halves.
  4. Morquio syndrome—irregular ossification of the femoral capital epiphyses results in flattening.
  5. Multiple epiphyseal dysplasia
  6. Meyer dysplasia—resembles multiple epiphyseal dysplasia but limited to the femoral heads.
  7. Chondrodysplasia punctata—punctate calcifications of developing epiphyses in fetus and infant which resolve in first few years of life, with disturbance of growth of affected bones. Cause may be genetic or maternal during pregnancy (e.g. mixed connective tissue disease, hyperemesis gravidarum, vitamin K deficiency and warfarin embryopathy).
  8. Trisomy 18 and 21.
  9. Prenatal infections.
  10. Zellweger syndrome (cerebrohepatorenal syndrome).
  11. Fetal alcohol syndrome—mostly calcaneum and lower extremities
32
Q

SOLITARY RADIOLUCENT

METAPHYSEAL BAND 8

A
  1. Normal neonate.
  2. Any severe illness.
  3. Metaphyseal fracture—especially in nonaccidental injury.
    Depending on the radiographic projection there may be the
    additional appearance of a ‘corner’ or ‘bucket-handle’ fracture.
  4. Healing rickets*.
  5. Leukaemia, lymphoma* or metastatic neuroblastoma.
  6. Congenital infections.
  7. Intrauterine perforation.
  8. Scurvy*
33
Q

ALTERNATING RADIOLUCENT AND

DENSE METAPHYSEAL BANDS 7

A
  1. Growth arrest lines—Harris or Park lines.
  2. Bisphosphonate therapy—‘zebra stripes’ appearance.
  3. Rickets*—especially those types that require prolonged treatment
    such as vitamin D-dependent rickets.
  4. Osteopetrosis.
  5. Chemotherapy.
  6. Chronic anaemias—sickle cell and thalassaemia.
  7. Treated leukaemia
34
Q

SOLITARY DENSE METAPHYSEAL BAND 6

A
  1. Normal infants.
  2. Lead poisoning—dense line in the proximal fibula is said to
    differentiate from normal. Other poisons include bismuth, arsenic,
    phosphorus, mercury fluoride and radium.
  3. Radiation.
  4. Congenital hypothyroidism.
  5. Osteopetrosis.
  6. Hypervitaminosis D.
35
Q

DENSE VERTICAL METAPHYSEAL LINES 4

A
1. Congenital rubella—celery stalk appearance. Less commonly in 
congenital CMV.
2. Osteopathia striata—± exostoses.
3. Hypophosphatasia.
4. Localized metaphyseal injury
36
Q

FRAYING OF METAPHYSES 4

A
  1. Rickets*.
  2. Hypophosphatasia—similar features as rickets.
  3. Chronic stress—in the wrists of young gymnasts; wide, irregular,
    asymmetrical widening of the distal radial growth plate and
    metaphyseal sclerosis.
  4. Copper deficiency
37
Q

CUPPING OF METAPHYSES 6

A
  1. Normal—especially distal ulna and proximal fibula of young
    children. No fraying.
  2. Rickets*—with widening of the growth plate and fraying.
  3. Trauma—to the growth plate/metaphysis. Localized changes.
  4. Bone dysplasias—e.g. achondroplasia, pseudoachondroplasia,
    metatropic dwarfism, diastrophic dwarfism, the metaphyseal
    chondrodysplasias, hypophosphatasia.
  5. Scurvy*—usually after fracture.
  6. Menkes disease—Copper deficiency can have similar appearances
38
Q

ERLENMEYER FLASK DEFORMITY

Dysplasias 3

A
  1. Osteopetrosis—in infantile and juvenile forms. Particularly striking
    in the similar disorder of dysosteosclerosis.
  2. Craniotubular disorders—e.g. metaphyseal dysplasia,
    craniometaphyseal dysplasia, craniodiaphyseal dysplasia,
    progressive diaphyseal dysplasia.
  3. Others—otopalatodigital syndrome type 1, Melnick-Needles
    syndrome and frontometaphyseal dysplasia
39
Q

ERLENMEYER FLASK DEFORMITY

Haematological 1

A
  1. Thalassaemia*.
40
Q

ERLENMEYER FLASK DEFORMITY

Depositional disorders 2

A

. Gaucher disease*.

2. Niemann-Pick disease*.

41
Q

ERLENMEYER FLASK DEFORMITY

Poisoning 1

A
  1. Lead poisoning—thick transverse dense metaphyseal bands are
    the classic manifestation of chronic infantile and juvenile lead
    poisoning. There may also be flask-shaped femora, which can
    persist for years before resolving
42
Q

FOCAL RIB LESION (SOLITARY OR
MULTIPLE) IN A CHILD
Neoplastic 4

A
  1. Metastases—typically neuroblastoma.
  2. Ewing sarcoma—can arise from bone or chest wall (Askin
    tumour) .
  3. Benign—e.g. osteochondroma, enchondroma.
  4. Langerhans cell histiocytosis*.
43
Q

FOCAL RIB LESION (SOLITARY OR
MULTIPLE) IN A CHILD
Nonneoplastic 3

A
  1. Healed rib fracture.
  2. Fibrous dysplasia.
  3. Osteomyelitis—bacterial, tuberculous or fungal.
44
Q

WIDENING OF THE SYMPHYSIS PUBIS
>10 mm in the newborn, >9 mm at 3 years, >8 mm at 7 years and
over.
Acquired 2

A
  1. Trauma.

2. Infection—low-grade osteomyelitis mimics osteitis pubis

45
Q

WIDENING OF THE SYMPHYSIS PUBIS

With normal ossification 9

A
  1. Bladder exstrophy—marked widening; ‘manta ray’ sign.
  2. Cloacal exstrophy
  3. Epispadias—degree of widening correlates well with severity of
    epispadias.
  4. Hypospadias.
  5. Imperforate anus with rectovaginal fistula.
  6. Urethral duplication.
  7. Prune-belly syndrome. ( partial or complete absence of the abdominal muscles, bilateral cryptorchidism and/or urinary tract malformations.)
  8. Sjögren–Larsson syndrome. ( is an inherited disorder characterized by scaling skin (ichthyosis), intellectual disability, speech abnormalities, and spasticity. Affected infants develop various degrees of reddened skin with fine scales soon after birth)
  9. Goltz syndrome (It is a type of ectodermal dysplasia, a group of heritable disorders causing the hair, teeth, nails, and glands to develop and function abnormally.)
46
Q

WIDENING OF THE SYMPHYSIS PUBIS

Poorly ossified cartilage 12

A
  1. Cleidocranial dysplasia*.
  2. Achondrogenesis/hypochondrogenesis.
  3. Campomelic dysplasia.
  4. Chondrodysplasia punctata.
  5. Hypophosphatasia.
  6. Congenital hypothyroidism.
  7. Spondyloepiphyseal dysplasia congenita.
  8. Spondyloepimetaphyseal dysplasia.
  9. Pyknodysostosis.
  10. Larsen syndrome.
  11. Wolf-Hirschhorn syndrome.
  12. Chromosome 9(p+) trisomy syndrome
47
Q

‘SHEETS’ OF CALCIFICATION IN

A CHILD 2

A
  1. Fibrodysplasia ossificans progressiva—manifests in childhood.
    Initially neck and trunk muscles involved. Short first metacarpal
    and metatarsal.
  2. Juvenile dermatomyositis
48
Q

PLATYSPONDYLY IN CHILDHOOD

Congenital platyspondyly 4

A
  1. Thanatophoric dwarfism—inverted ‘U’- or ‘H’-shaped vertebrae
    with markedly increased disc space/body height ratio. Telephone
    handle-shaped long bones.
  2. Metatropic dwarfism—flat-appearing vertebral bodies, but large
    disc spaces mean that overall spinal height is near normal in
    infancy. As childhood progresses, relative spinal height reduces.
  3. Osteogenesis imperfecta—type IIA.
  4. Homozygous achondroplasia
49
Q

PLATYSPONDYLY IN CHILDHOOD

Platyspondyly in later childhood 3

A
  1. Morquio syndrome.
  2. Spondyloepiphyseal dysplasia congenita/tarda.
  3. Kniest syndrome.
50
Q

PLATYSPONDYLY IN CHILDHOOD

Acquired platyspondyly 4

A
  1. Scheuermann’s disease—irregular endplates and Schmorl’s nodes
    in the thoracic spine of children and young adults. Disc-space
    narrowing. May progress to a severe kyphosis.
  2. Langerhans cell histiocytosis*—the spine is more frequently
    involved in eosinophilic granuloma and Hand-Schüller-Christian
    disease than in Letterer-Siwe disease. The thoracic and lumbosacral
    spine are the usual sites of disease. Disc spaces are preserved.
  3. Osteogenesis imperfecta—multiple spinal compression fractures,
    resulting in loss of height and spinal deformity.
  4. Sickle cell anaemia—characteristic step-like depression in the
    central part of the endplates (‘H-shaped’ vertebrae).
51
Q

ANTERIOR VERTEBRAL BODY BEAKS
7
Involves 1–3 vertebral bodies at the thoracolumbar junction,
usually associated with a kyphosis. Hypotonia is probably the
common denominator, leading to an exaggerated thoracolumbar
kyphosis, anterior herniation of the nucleus pulposus and
subsequently an anterior vertebral body defect

A
  1. Mucopolysaccharidoses*—with platyspondyly in Morquio; this is
    probably a more useful distinguishing characteristic than the
    position of the beak (inferior or middle), which is variable.
  2. Achondroplasia*.
  3. Mucolipidoses.
  4. Pseudoachondroplasia.
  5. Congenital hypothyroidism.
  6. Down’s syndrome*.
  7. Neuromuscular diseases
52
Q

MULTIFOCAL BONE MARROW LESIONS
ON MRI
Malignancy 2

A

. Metastases—commonly from neuroblastoma, leukaemia,
lymphoma, clear cell sarcoma, rhabdomyosarcoma, retinoblastoma,
osteosarcoma and Ewing sarcoma
2. Langerhans cell histiocytosis*—low T1 signal, high signal on T2
fatsat sequences, variable enhancement pattern

53
Q

MULTIFOCAL BONE MARROW LESIONS
ON MRI
Dysplasias 3

A
  1. Hereditary multiple osteochondromas.
  2. Enchondromatosis.
  3. Polyostotic fibrous dysplasia—isointense with focal low signal
    areas on T1, heterogeneous on T2, patchy variable enhancement
54
Q

MULTIFOCAL BONE MARROW LESIONS
ON MRI
Infection/inflammatory 2

A
  1. Multifocal osteomyelitis—may present with nonenhancing fluid
    collections and rim-enhancing abscesses in bone, joint effusions
    and cartilaginous involvement.
  2. Chronic recurrent multifocal osteomyelitis—idiopathic,
    noninfective, inflammatory disorder. Diagnosis of exclusion. Tends
    to occur at epiphyseal/metaphyseal regions in long bones,
    especially the clavicles (rare for haematogenous osteomyelitis)
55
Q

MULTIFOCAL BONE MARROW LESIONS
ON MRI
Trauma/infarction
2

A
  1. Multiple stress fractures—as seen in gymnasts and young athletes
    from repetitive strain.
  2. Multifocal infarction/avascular necrosis—children prone to this
    include those with sickle cell disease, corticosteroid exposure,
    storage disorders and inflammatory arthritis. May also occur
    secondary to radiotherapy
56
Q

SOFT-TISSUE TUMOURS AND MASSES

Vascular tumours
3

A
  1. Infantile haemangioma—usually solitary, first noticed around time
    of birth with a period of proliferation before involution (90% will
    have involuted by 9 years).
  2. Congenital haemangioma—similar appearance to infantile type,
    but does not grow after birth; depending on subtype they can
    involute. RICH, PICH, NICH
  3. Kaposiform haemangioendothelioma—associated with
    Kasabach-Merritt syndrome ( thrombocytopenia, coagulopathy)
57
Q

SOFT-TISSUE TUMOURS AND MASSES
Vascular malformations (can also occur in
combination with each other) 4

A
  1. Arteriovenous malformation—high flow lesion, 60% are
    diagnosed at birth.
  2. Venous malformations—low flow lesion, phleboliths commonly
    present.
  3. Lymphatic malformation—previously referred to as cystic
    hygromas.
  4. Capillary malformations—usually do not require imaging to
    diagnose
58
Q

SOFT-TISSUE TUMOURS AND MASSES

Fat-containing soft-tissue lesions 6

A
  1. Lipoma—usually no vascularity, can have a fibrous capsule that
    may enhance, but should not internally enhance on MRI.
    Uncommon in children.
  2. Lipoblastoma—benign tumour, exclusively found within first 3
    years of life. Slightly lower T1 signal compared to normal fat.
  3. Angiolipoma—slow growing, painful, ± vascular flow (in 25%).
  4. Lipomatosis—infiltrative adipose tissue involving multiple layers
    (muscle, skin and bone). Usually <2 years of age.
  5. Fibrous hamartoma of infancy (FHI)—>90% occur in infancy,
    most common around shoulder or inguinal region. Subcutaneous
    location. Contains fat and T1/T2 hypointense strands of fibrous
    tissue.
  6. Lipofibromatosis—benign tumour of young children, most
    common in hands and feet (in contrast to FHI). Contains fat and
    fibrous tissue, often infiltrative
59
Q

SOFT-TISSUE TUMOURS AND MASSES

Fibrous soft-tissue lesions 13

A
  1. Rhabdomyosarcoma—most common soft-tissue sarcoma in
    children. Can occur anywhere (not just in skeletal muscle), e.g.
    orbit, pharynx, sinuses, paratesticular, bladder, etc. Nonspecific
    imaging features.
  2. Synovial sarcoma—usually in adolescents, most commonly in
    soft tissues near the knees. Calcification, if present, is suggestive.
  3. Infantile myofibroma—typically <2 years of age. Benign, usually
    solitary and subcutaneous, but can be multiple (myofibromatosis)
    and deep, involving muscle, bone or viscera (the latter is rare and
    conveys a poor prognosis). Bone lesions are typically metaphyseal
    and well-defined. Often regresses spontaneously if viscera are not
    involved.
  4. Fibrous hamartoma of infancy—contains fat; see above.
  5. Lipofibromatosis—contains fat; see above.
  6. Nodular fasciitis—see Section 4.4. Can occur in children, usually
    adolescents (except cranial fasciitis that occurs <2 years of age)
  7. Desmoid tumour—see Section 4.4. May be the first sign of
    Gardner syndrome (‘Gardner fibroma’).
  8. Inflammatory pseudotumour—can occur anywhere, most
    commonly lung, mesentery and omentum. Variable imaging
    appearance.
  9. Fibromatosis colli—<6 months of age, benign fibroblastic
    proliferation specific to the sternocleidomastoid muscle. Unilateral
    fusiform muscle thickening is characteristic.
  10. Fibroma of tendon sheath—typically involves tendons of the
    hands. T2 hypointense, no/minimal enhancement.
  11. Infantile digital fibroma—<3 years of age, subcutaneous nodule
    in dorsolateral aspect of digits.
  12. Infantile fibrosarcoma—typically <2 years of age. Large painless
    mass, rapid growth. Heterogeneous and hypervascular on US/
    MRI, can cause adjacent bone erosion.
  13. Low-grade fibromyxoid sarcoma—can occur in children.
    Alternating T2 hyper- and hypointense areas due to mixture of
    myxoid and fibrous components.
60
Q

SOFT-TISSUE TUMOURS AND MASSES

Soft-tissue tumour mimics 4

A
  1. Posttraumatic lesions—e.g. contusion, fat necrosis, foreign body
    reaction or cellulitis. Typically painful and ill-defined on imaging.
  2. Subcutaneous granuloma annulare—rapidly growing painless
    subcutaneous nodule, typically in children <5 years of age. Most
    common on extensor surface of extremities (especially pretibial) or
    in scalp. Nonspecific ill-defined lesion on US/MRI. Resolves
    spontaneously.
  3. Pilomatricoma—often calcified; see Section 4.2.
  4. Microcystic lymphatic malformation—appears solid on US ±
    enhancement on MRI.
61
Q

OSTEOCHONDRITIS DISSECANS

OSTEOCHONDRAL DEFECTS

A

• Multiple adjacent bone cysts at margin of defect, or a single cyst
>5 mm
• Fluid separating bone fragment from adjacent bone (fluid rim)
• Multiple disruptions in subchondral plate

Common locations
• Arms: capitellum of humerus, radial head.
• Legs: anteromedial talar dome, lateral aspect of medial femoral
condyle.

62
Q

ACUTE UPPER AIRWAY OBSTRUCTION IN

A CHILD 7

A
  1. Laryngotracheobronchitis (croup)—most common 6 months–3
    years. Narrowing of the glottic and subglottic airway. Ballooning of
    hypopharynx on lateral view. ‘Steepling’ of upper airway on frontal
    view.
  2. Acute epiglottitis—the epiglottis is swollen ± shortened. Other
    components of the supraglottic region (aryepiglottic folds,
    arytenoids, uvula and prevertebral soft tissues) are also swollen.
    The hypopharynx and pyriform sinuses are distended with air.
  3. Abscess—retropharyngeal is more common <2 years as
    retropharyngeal nodes atrophy thereafter. Enlarged prevertebral
    soft tissues ± gas or air-fluid level. Rim enhancement seen post
    contrast on CT or MRI. Role for US in diagnosis and follow-up.
    Peritonsillar is more common in teenagers and young adults.
  4. Oedema—caused by angioedema (allergic, anaphylactic or
    hereditary), inhalation of noxious gases or trauma. Predominantly
    laryngeal oedema.
  5. Foreign body—more commonly occludes a major bronchus rather
    than the upper airway.
  6. Choanal atresia—most common congenital nasal abnormality;
    bilateral (33%) or unilateral (R>L), bony (90%) or membranous,
    complete or incomplete. When bilateral and complete, it presents
    with severe respiratory distress at birth (infants are primarily nasal
    breathers until 6 weeks–6 months of age). Incomplete obstruction
    is associated with respiratory difficulty during feeding. Diagnosis is
    determined by failure to pass a catheter through the nose,
    nasopharyngography or CT.
  7. Retropharyngeal haemorrhage—due to trauma, neck surgery,
    direct carotid arteriography or bleeding disorders. Widened
    retropharyngeal soft-tissue space
63
Q

CHRONIC UPPER AIRWAY
OBSTRUCTION IN A CHILD
Nasal 3

A
  1. Choanal atresia—see Section 14.33.
  2. Juvenile nasopharyngeal angiofibroma—nearly always in
    adolescent males. Symptoms of nasal obstruction and/or recurrent
    atraumatic epistaxis. Benign but locally aggressive, causing bony
    remodelling. Avid enhancement on CT/MRI. Plain films may show:
    (a) Anterior bowing of the posterior wall of the maxillary antrum.
    (b) Deviation of the nasal septum.
    (c) A nasopharyngeal soft-tissue mass with erosion of contiguous
    bony structures.
  3. Antrochoanal polyp.
64
Q

CHRONIC UPPER AIRWAY
OBSTRUCTION IN A CHILD
Supraglottic 4

A
  1. Grossly enlarged tonsils and adenoids.
  2. Laryngomalacia—presents at or shortly after birth, persists for
    several months and usually resolves by 2 years. Diagnosis is
    confirmed by direct laryngoscopy, but fluoroscopy reveals anterior
    motion of aryepiglottic folds and distension of hypopharynx.
  3. Micrognathia—e.g. in Pierre Robin syndrome.
  4. Cysts—of the epiglottis or aryepiglottic folds. The degree of
    obstruction depends on size and location
65
Q

CHRONIC UPPER AIRWAY
OBSTRUCTION IN A CHILD
Glottic 1

A
  1. Laryngeal polyp, papilloma or cyst
66
Q

CHRONIC UPPER AIRWAY
OBSTRUCTION IN A CHILD
Subglottic and tracheal 7

A
  1. Tracheomalacia—weakness of tracheal wall, may be:
    (a) Primary—e.g. premature infants; also in cartilage disorders, e.g. polychondritis, chondromalacia, mucopolysaccharidoses.
    (b) Secondary.
    (i) Following prolonged intubation.
    (ii) With tracheoesophageal fistula/oesophageal atresia.
    (iii) With vascular ring or other extrinsic vascular compression.
    (iv) With long-standing external compression by tumour, etc.
  2. Vascular ring.
    (a) Double aortic arch.
    (b) Right arch with left-sided duct/ductal ligament.
    (c) Pulmonary artery sling—often coexists with intrinsic airway
    narrowing from complete cartilage rings.
    (d) Anomalous subclavian artery ± large Kommerell diverticulum ( bulbous configuration of the origin of an aberrant left subclavian artery in the setting of a right-sided aortic arch.)
  3. Following prolonged inflammation—e.g. prolonged tracheal intubation (may be fixed stenosis or malacia) or chronic aspiration (laryngeal cleft, H-type tracheoesophageal fistula, etc.).
  4. External compression from other structures—e.g. adenopathy, foregut duplication cyst, teratoma, lymphovascular malformation, enlarged heart or pulmonary trunk (especially in tetralogy of Fallot with absent pulmonary valve or severe pulmonary hypertension).
  5. Subglottic haemangioma—the most common subglottic soft-tissue mass in infancy. Occurs <6 months. 50% have associated cutaneous haemangiomas. Characteristically produces an asymmetrical narrowing of the subglottic airway.
  6. Intrinsic congenital obstruction—e.g. tracheal stenosis due to complete cartilage rings, webs, etc. Can result in congenital high airway obstruction syndrome (CHAOS).
  7. Respiratory papillomatosis—occurs anywhere from the nose to the lungs; most cases are limited to the larynx. Irregular soft-tissue masses ± cavitation of lung lesions.
67
Q

NEONATAL RESPIRATORY DISTRESS
Pulmonary causes With no mediastinal shift
8

A
  1. Respiratory distress syndrome (RDS)—surfactant deficiency
    disorder, occurs in premature infants. Symptomatic soon after birth
    but maximum radiographic findings develop at 12–14 hours. Fine
    granular pattern throughout both lungs, air bronchograms, and
    later, obscured heart and diaphragm outlines. Small lung volumes
    due to diffuse microatelectasis. Often cardiomegaly. May progress
    to a complete ‘white-out’. Frequent ventilator-associated
    complications include pulmonary interstitial emphysema,
    pneumomediastinum and pneumothorax, all of which can lead to
    mediastinal displacement. Patchy clearing of infiltrate occurs after
    exogenous surfactant therapy. As oxygenation improves,
    bidirectional or left-to-right shunting through the patent ductus
    arteriosus may lead to pulmonary oedema, cardiomegaly and
    occasionally pulmonary haemorrhage
  2. Transient tachypnoea of the newborn (TTN)—prominent
    interstitial markings and vessels, thickened septa, small effusions
    and occasionally mild cardiomegaly. May mimic RDS, MAS or
    neonatal pneumonia, but resolves within 2–3 days.
  3. Meconium aspiration syndrome (MAS)—predominantly in term
    and postmature babies. Coarse linear and irregular opacities of
    uneven size, generalized hyperinflation and focal areas of collapse.
    Spontaneous pneumothorax in 20%. Pleural effusion in up to 2/3;
    supposedly never seen in RDS. No air bronchograms. High risk of
    superimposed infection.
  4. Pneumonia—in <1% of newborns. Risk factor: prolonged rupture
    of membranes. Most commonly group B streptococcus. Segmental
    or lobar consolidation. Pleural effusions may be large, and suggest
    diagnosis. May resemble RDS or MAS, but should be suspected if
    unevenly distributed.
  5. Pulmonary haemorrhage—75% are <2.5 kg. Onset at birth or
    delayed several days. May occur after surfactant therapy, probably
    due to left-to-right shunting. Resembles MAS or RDS.
  6. Upper airway obstruction—e.g. choanal atresia, micrognathia.
  7. Abnormal thoracic cage.
    (a) Neuromuscular disorders—often with thin ribs and clavicles.
    (b) Skeletal dysplasias—e.g. Jeune’s asphyxiating thoracic
    dysplasia, thanatophoric dwarfism, osteogenesis imperfecta
    and metatropic dwarfism.
    (c) Pulmonary hypoplasia—e.g. due to fetal renal failure (Potter
    sequence) or primary (rare).
    (d) Major abdominal wall defects (exomphalos/gastroschisis)—
    short, down-sloping ribs with ‘long’ chest.
  8. Infant-onset childhood interstitial lung disease (chILD)—wide
    variety of rare pathologies (see Section 14.37). Variable appearance
    from complete bilateral white-out to normal
68
Q

NEONATAL RESPIRATORY DISTRESS

With mediastinal shift away from the abnormal side 5

A
  1. Diaphragmatic hernia—six times more common on the left side.
    Multiple lucencies due to gas-containing bowel in the chest.
    Herniated bowel may appear solid if X-rayed too early, but there
    will still be a paucity of gas in the abdomen. Liver herniation
    present in large hernias, bad prognostic sign. Displaces umbilical
    venous catheters.
  2. Congenital lobar overinflation (CLO)—left upper > right middle
    > right upper lobe, with compression of the lung base (cf.
    pneumothorax which produces generalized compression). CT is
    useful, particularly to exclude extrinsic compression of a bronchus
    by an aberrant vessel or foregut duplication cyst.
  3. Large congenital pulmonary airway malformation (CPAM)—
    translucencies of various shapes and sizes scattered throughout an area of opaque lung with well-defined margins. Types 0–IV, varying
    from cystic to apparently solid. Generally asymptomatic unless very
    large or superadded infection.
  4. Pneumothorax—may complicate resuscitation or positive pressure
    ventilation, or may be spontaneous. Spontaneous pneumothorax is
    associated with pulmonary hypoplasia, e.g. in Potter sequence. In
    the supine neonate, pleural air collects anteriorly and may not
    collapse the lung medially. In the absence of a lung edge, other
    signs include:
    (a) Sharp ipsilateral heart border.
    (b) Depression or inversion of the ipsilateral hemidiaphragm with
    a deep lateral sulcus.
    (c) Sharp ipsilateral parietal pleura in the upper medial part of the
    hemithorax. If there is tension this may herniate across the
    superior mediastinum.
    (d) Medial deviation of the ipsilateral compressed thymic lobe.
    (e) Mediastinal shift to the contralateral side.
  5. Pleural fluid—effusion (especially in congenital heart disease),
    chylothorax (especially in Noonan and Turner syndromes),
    empyema (rare)
69
Q

NEONATAL RESPIRATORY DISTRESS

With mediastinal shift towards the abnormal side 3

A
  1. Atelectasis—most commonly due to incorrect placement of an
    endotracheal tube down a major bronchus. Other causes include
    extrinsic compression (e.g. large duplication cyst, aberrant
    vasculature), intrinsic causes (e.g. tracheobronchomalacia), luminal
    obstruction by a large mucus plug or, rarely, primary atelectasis
    without another abnormality.
  2. Pulmonary agenesis/aplasia—rare. May be difficult to
    differentiate from collapse but other congenital defects, especially
    hemivertebrae, are often present. Agenesis = no bronchus; aplasia
    = rudimentary bronchus present.
  3. Unilateral pulmonary hypoplasia—most commonly due to
    compression, e.g. by diaphragmatic hernia. May also be associated
    with vascular anomalies, e.g. absent pulmonary artery and
    anomalous venous drainage (scimitar syndrome).
70
Q

NEONATAL RESPIRATORY DISTRESS

Other causes 4

A
  1. Cardiac causes—e.g. congenital heart diseases.
  2. Cerebral causes—e.g. haemorrhage, oedema, drugs. After
    cardiopulmonary causes, these account for 50% of the remainder.
  3. Metabolic causes—metabolic acidosis, hypoglycaemia and
    hypothermia.
  4. Abdominal causes—massive organomegaly, e.g. polycystic
    kidneys, elevating the diaphragms
71
Q

RING SHADOWS IN A CHILD

Neonate 5

A
  1. Diaphragmatic hernia—unilateral.
  2. Pulmonary interstitial emphysema (PIE)—secondary to ventilator
    therapy. Linear lucencies, unilateral or bilateral. Usually transient,
    but may persist.
  3. CPAM—Stocker types I/IV (at least one cyst >2 cm) and type II (all
    cysts <2 cm). Unilateral focal lucency/lucencies. Type III is
    microcystic and appears solid.
  4. Bronchopulmonary dysplasia (BPD)—aka chronic lung disease of
    prematurity. Bilateral, diffuse ‘bubbly lung’ appearances, with
    alternating areas of overinflation and atelectasis.
  5. Cystic lung disease in chromosomal disorders—especially
    Down’s.
72
Q

PULMONARY RING SHADOWS IN A CHILD

Older child 6

A
  1. Bronchiectasis—postinfective, cystic fibrosis, primary ciliary
    dyskinesia, immunodeficiency, etc.
  2. Pneumatocoeles—e.g. postinfective, ventilation-induced.
  3. Respiratory papillomatosis—multiple cystic lesions with nodular
    walls on CT. Laryngeal and tracheal involvement is usually also
    present.
  4. Pleuropulmonary blastoma (type 1)—indistinguishable from type
    I/IV CPAM on imaging and similar histologically to type IV CPAM.
  5. Langerhans cell histiocytosis*—lung involvement very rare in
    children.
  6. Neurofibromatosis*—upper zone cysts/bullae
73
Q

INTERSTITIAL LUNG DISEASE UNIQUE
TO CHILDHOOD
Very rare conditions divided into infant or later onset 2

A
  1. Disorders of infancy.
    (a) Diffuse developmental disorders—e.g. congenital alveolar
    dysplasia, alveolar capillary dysplasia with misalignment of
    pulmonary veins.
    (b) Lung growth abnormalities—e.g. pulmonary hypoplasia,
    chronic BPD, cystic disease in Down’s.
    (c) Conditions of undefined origin—e.g. pulmonary interstitial
    glycogenosis, neuroendocrine hyperplasia of infancy.
    (d) Genetic surfactant dysfunction disorders—most commonly
    surfactant protein B/C or ABCA3 mutations.
  2. Disorders not specific to infancy.
    (a) Normal host—e.g. postinfective constrictive obliterative
    bronchiolitis.
    (b) Systemic disease processes—e.g. storage disorders (Gaucher,
    Niemann-Pick).
    (c) Immunocompromise—e.g. lymphocytic interstitial pneumonitis
    in HIV (rare but much more common in children with AIDS
    versus adults with AIDS).
    (d) Masqueraders of interstitial lung disease—e.g. pulmonary
    hypertension, lymphatic disorders.
74
Q

ANTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Congenital 3

A
  1. Normal thymus—see Section 14.38.
  2. Lymphangioma—nearly all extend into the mediastinum from the
    neck. Cystic.
  3. Morgagni hernia—anterior, usually on the right side.
75
Q

ANTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Neoplastic 5

A
  1. Lymphoma* and leukaemia—most common cause of an anterior
    mediastinal mass in children. The majority are due to Hodgkin
    disease. At presentation, enlarged mediastinal lymph nodes (LN)
    are seen in 85% of Hodgkin, 50% of non-Hodgkin and 5%–10%
    of leukaemias. The lymphadenopathy is usually confluent and
    homogeneous on CT. Comparing mediastinal involvement in
    Hodgkin versus non-Hodgkin lymphoma After lymphoma treatment, a residual anterior mediastinal mass
    may present a diagnostic dilemma. If CT shows this to be
    homogeneous and there is no other lymphadenopathy then a
    tumour is unlikely to be present. PET-CT is currently used to risk
    stratify and determine whether radiotherapy is needed.
  2. Germ cell tumours—5%–10% of germ cell tumours arise in the
    mediastinum. Two age peaks: at 2 years and in adolescence. 60%
    are benign teratomas. Endodermal sinus (yolk sac) tumours are
    more aggressive. Seminomas rare. Tumours may contain
    calcification (including teeth), fat and cystic/necrotic areas. Large size, marked mass effect and local infiltration suggest an aggressive
    lesion.
  3. Thymic cysts—either congenital, or in young children with LCH,
    or in HIV/EBV-driven lymphoproliferative disease.
  4. Thymolipoma—contains fat and thymic tissue.
  5. Thymoma—1%–2% of mediastinal tumours in childhood. Most
    occur >10 years of age. Linear calcification in 10%. Only rarely
    associated with myasthenia gravis.
76
Q

ANTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Inflammatory 1

A
  1. Lymphadenopathy—less common than neoplasia. Most frequent
    causes are TB and histoplasmosis. Involved nodes typically show
    central necrosis
77
Q

MIDDLE MEDIASTINAL MASSES

IN CHILDHOOD 20%

A

Neoplastic
Most middle mediastinal tumours are extensions of those
which arise primarily in the anterior mediastinum (see
Section 14.39).
Inflammatory
1. Lymphadenopathy—TB, histoplasmosis and sarcoidosis (NB:
pulmonary sarcoid is very rare before early teens).

78
Q

MIDDLE MEDIASTINAL MASSES
IN CHILDHOOD
Congenital 4

A
  1. Foregut duplication cysts—account for 10%–20% of paediatric
    mediastinal masses. The spectrum of abnormalities includes:
    (a) Bronchogenic cyst—abnormal lung budding and
    development of ventral foregut during first trimester. Round/
    oval, well-defined, unilocular and homogeneous mass; usually
    0–20 HU, but can be up to 100 HU due to mucus,
    haemorrhage or even milk of calcium contents. There may be
    airway obstruction and secondary infection, both within the
    cyst and in the surrounding lung. May rarely communicate
    with the tracheobronchial tree, resulting in a cavity ± infection.
    Most commonly attached to the carina, but can be located
    anywhere along tracheobronchial tree, e.g. paratracheal, hilar,
    intrapulmonary, paraoesophageal.
    (b) Oesophageal duplication cyst—abnormal development of the
    posterior division of the embryonic foregut. Less common
    than bronchogenic cysts, usually larger and along the upper
    third of the oesophagus, situated to the right of the midline
    extending into the posterior mediastinum. May produce
    symptoms related to oesophageal or tracheobronchial tree
    compression. May contain ectopic gastric mucosa (+ve 99mTc-pertechnetate scan), which causes ulceration,
    haemorrhage or perforation. Communication with the
    oesophageal lumen is rare.
    (c) Neurenteric cyst—failure of separation of gastrointestinal tract
    from primitive neural crest. Located in the middle or posterior
    mediastinum, contains neural tissue and maintains a
    connection with the spinal canal. R>L. Vertebral body
    anomalies (hemivertebra, butterfly vertebra and scoliosis) are
    usually superior to the cyst.
  2. Lymphangioma—5% of lymphangiomas in the neck extend into
    the mediastinum. Most are present at birth. Cystic ± solid
    components on imaging.
  3. Congenital hiatus hernia—less common than other congenital
    diaphragmatic hernias.
  4. Achalasia—rare in children
79
Q

POSTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Neoplastic 2

A
  1. Ganglion cell tumours—neuroblastoma (most malignant, usually
    <5 years), ganglioneuroblastoma (malignant potential, age 5–10 years) and ganglioneuroma (benign, usually >10 years). Imaging
    features of all three types are similar but metastases do not occur
    with ganglioneuroma. Plain films show a paravertebral soft-tissue
    mass with calcification in 30%. Thinning/separation of posterior
    ribs and enlargement of intervertebral foramina may be seen. CT
    shows calcification in 90%. Both CT and MRI may show extradural
    extension.
  2. Nerve sheath tumours—benign (schwannoma, neurofibroma) or
    malignant peripheral nerve sheath tumour
80
Q

POSTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Congenital 1

A
  1. Bochdalek hernia—most present at, or shortly after, birth with
    respiratory distress, but 5% present after the neonatal period.
    Rarely it may complicate group B streptococcal infection. A
    herniated liver/kidney may mimic a mass or pleural effusion, and a
    herniated bowel may mimic a pneumothorax, pneumatocoeles or
    CPAM. Bochdalek hernias include:
    (a) Persistence of the pleuroperitoneal canal with a posterior lip of
    diaphragm.
    (b) Larger defects with no diaphragm.
    (c) Herniation through the costolumbar triangles.
81
Q

POSTERIOR MEDIASTINAL MASSES
IN CHILDHOOD
Other 1

A
  1. Extramedullary haematopoiesis—in children, usually related to
    thalassaemia or sickle cell disease. Single or multiple paravertebral
    masses with features of the underlying cause
82
Q

SOLITARY PULMONARY MASS
IN CHILDHOOD
Pseudomass lesions 4

A
  1. Round pneumonia—may contain air-bronchograms. Rarer >8
    years.
  2. Encysted pleural effusion—usually an elliptiform mass in right
    midzone. Lateral film confirms.
  3. Mucus plug in cystic fibrosis—can be large. CT confirms
    location.
  4. Vasculitis
83
Q

SOLITARY PULMONARY MASS
IN CHILDHOOD
Nonneoplastic lesions 6

A
  1. Pulmonary sequestration—focal area of lung that does not
    communicate with the bronchial tree or pulmonary arteries,
    appearing as a nonaerated mass with systemic arterial supply
    (usually from descending aorta). Two types:
    (a) Intralobar—most common type. No separate pleural covering,
    usually has pulmonary venous drainage. Typically in lower
    lobes (L>R). Usually presents in older children or adolescents
    with recurrent infection.
    (b) Extralobar—has its own separate pleural covering, usually has
    systemic venous drainage. Typically in left lower lobe, but can
    be subdiaphragmatic. Usually presents in neonates with
    respiratory distress. Often associated with other congenital
    anomalies.
  2. Intrapulmonary bronchogenic cyst—well-defined rounded lesion
    that may contain air–fluid level, particularly if a previous infection.
  3. CPAM—type III is microcystic and appears solid. Type I/II are fluidfilled at birth and gradually become air-filled (often reimaged at 3
    months). Note that CPAM-sequestration hybrid lesions can occur
    (looks like CPAM but has systemic arterial supply).
  4. Granuloma—most common after TB or histoplasmosis. Usually
    small and calcified.
  5. Pulmonary AVM—may visualize draining vein.
  6. Bochdalek hernia—due to defect in posterior diaphragm; located
    at lung base, well-defined cranial margin. May contain abdominal
    viscera, e.g. kidney
84
Q

SOLITARY PULMONARY MASS
IN CHILDHOOD
Neoplastic lesions 7

A

Malignant
1. Solitary metastasis—most commonly Wilms tumour and
sarcomas. Note that ~one-third of lung nodules in children with a
known primary tumour are NOT metastases, e.g. drug reaction,
intrapulmonary lymph node, etc. Lung metastases are rarely an
incidental finding in children.
2. Neuroendocrine tumour—80% are carcinoids. Usually malignant,
frequently endobronchial, causing lobar collapse or overinflation.
Carcinoid syndrome less common in pulmonary carcinoids than
tumours elsewhere.
3. Pleuropulmonary blastoma (PPB)—may be cystic (type I, mimics
CPAM), mixed (type II) or solid (type III). Can be very large, often
peripheral and locally invasive.
4. Bronchogenic carcinoma—most commonly mucoepidermoid
carcinoma.
Benign
1. Inflammatory myofibroblastic tumour—neoplastic subset of
inflammatory pseudotumours. Most common primary lung
neoplasm in children. Usually benign but can be malignant.
Variable size, usually peripheral. Calcified in 25%.
2. Hamartoma—occasionally calcified. Slow-growing, well-defined.
3. Chondroma—e.g. in Carney triad.

85
Q

MULTIPLE PULMONARY NODULES IN
A CHILD
Benign 6

A
  1. Miliary TB*/other granulomatous infection—miliary pattern of
    haematogenous spread should be distinguished from ‘tree-in-bud’
    pattern of endobronchially disseminated TB.
  2. Septic emboli—frequently cavitary.
  3. Wegener’s granulomatosis*—may cavitate.
  4. Respiratory papillomatosis—represents pulmonary seeding of
    laryngeal papillomas, occurring in 1% of cases. Nodular and
    cystic lesions. Poor prognosis. Risk of malignant transformation.
  5. Prior varicella infection—can result in multiple small calcified
    granulomas.
  6. Multiple AVMs—2/3 associated with HHT. Multiple in most cases,
    usually lower lobes
86
Q

MULTIPLE PULMONARY NODULES IN
A CHILD
Malignant 2

A
  1. Multiple pulmonary metastases—Wilms tumour and sarcomas
    (calcified nodules in osteosarcoma) are the most common primary
    sites. Multiple nodules are more likely to be malignant than a
    single nodule.
  2. Lymphoma* or PTLD.
87
Q

SITUS AND CARDIAC MALPOSITIONS

Visceral situs 4

A
  1. Situs solitus—normal position, i.e. liver on the right, gastric
    bubble on the left and normal airway anatomy.
  2. Situs inversus—completely switched positions, i.e. liver on the left,
    stomach bubble on the right, inverted airway anatomy (i.e. earlier
    take-off of the left-sided upper lobe bronchus).
  3. Left atrial isomerism (LAI)—bilateral left-sidedness, i.e. long main
    bronchi passing inferior to the pulmonary arteries with late
    upper-lobe take-off (as per a normal left bronchus), bilateral
    bilobed lungs, azygous continuation of the IVC (absent
    intrahepatic IVC with resultant large azygous venous system)
    and polysplenia. Associated with complex congenital heart
    disease.
  4. Right atrial isomerism (RAI)—bilateral right-sidedness, i.e.
    bilateral short main bronchi with early upper-lobe take-off (as per a
    normal right bronchus), bilateral trilobed lungs, ± asplenia.
    Associated with more severe cardiac and extracardiac
    malformations than left atrial isomerism
88
Q

CONGENITAL HEART DISEASES

Plethoric Acyanotic 4

A
  1. VSD
  2. ASD
  3. AVSD
  4. APW
89
Q

CONGENITAL HEART DISEASES

Plethoric Cyanotic 6

A
  1. d-TGA (vessels are switched, cf l TGA - ventricles switched)
  2. TAPVD
  3. Truncus arteriosus ( common trunk + VSD, 4 types)
  4. HLHS ( hypoplastic left heart xd, small asc aorta)
  5. Tricuspid atresia + TGA
  6. Single ventricle
90
Q

CONGENITAL HEART DISEASES

Oligaemic Cyanotic 4

A
  1. Tetralogy of Fallot
  2. Ebstein’s anomaly
  3. Tricuspid atresia
  4. Pulmonary atresia
91
Q

CONGENITAL HEART DISEASES

Normal lung fields Acyanotic 3

A
  1. Aortic stenosis
  2. Coarctation of aorta
  3. Pulmonary stenosis
92
Q

ABDOMINAL MASS IN A CHILD

Renal (55%) 3

A
  1. Renal tumours
  2. Hydronephrosis
  3. Cysts
93
Q

ABDOMINAL MASS IN A CHILD

Non-renal retroperitoneal (23%) 9

A
  1. Neuroblastoma (21%)—most common solid extracranial
    childhood malignancy. 90% <5 years, median age 2 years.
    Accounts for 50% of all neonatal tumours. 70% are metastatic at
    presentation.
    (a) Site—adrenal (40%), abdominal sympathetic chain (25%),
    posterior mediastinal sympathetic chain (15%), neck (5%),
    pelvis (5%) and unknown (10%).
    (b) Clinical presentation.
    (i) Local effects—pain, mass, spinal cord compression,
    dyspnoea, dysphagia.
    (ii) Effects of metastases—blueberry muffin syndrome (skin
    metastases), scalp masses, limping, bone pain, weight
    loss, anaemia, fatigue, etc.
    (iii) Effects of hormone secretion—severe diarrhoea (due to
    vasoactive intestinal peptides), hypertension, flushing and
    sweating.
    (iv) Opsomyoclonus—jerky eye movements, myoclonic jerks
    and cerebellar ataxia; 50% will have neuroblastoma,
    therefore must investigate thoroughly.
    (c) Plain films—calcification (in 2/3), loss of psoas outline, bony
    metastases, enlarged intervertebral foramina, and in the chest,
    abnormal posterior ends of ribs.
    (d) US—heterogeneous echogenic mass + vascularity ±
    calcification.
    (e) CT—heterogeneous soft-tissue mass with calcification in nearly
    all. Encasement rather than displacement of major vessels.
    Paravertebral fat plane is often obliterated ± intraspinal
    extension via the intervertebral foramina.
    (f) MRI—heterogeneously T1 hypointense and T2 hyperintense.
    Calcification is not as readily recognized as on CT, but MRI is
    superior for lymph-node metastases, liver metastases and
    extradural spread of tumour.
    (g) Nuclear imaging—bone scan (for cortical disease) and MIBG
    scan (for medullary disease) are complementary techniques to
    identify skeletal metastases.
  2. Lymphoma*—uncommon in the absence of mediastinal disease.
    NHL > Hodgkin disease in children <5 years.
  3. Germ cell tumours—usually represent a metastasis from a gonadal
    primary. The most common primary retroperitoneal GCT in
    children is benign teratoma; typically it contains variable amounts
    of fluid, soft tissue, fat and calcification.
  4. Other ganglion cell tumours—i.e. ganglioneuroma (benign,
    usually >10 years) and ganglioneuroblastoma (malignant
    potential, age 5–10 years). Similar imaging features to
    neuroblastoma, but ganglioneuroma does not metastasize,
    is less commonly calcified and may have a characteristic whorled
    appearance on MRI.
  5. Other adrenal masses—see Section 14.56.
  6. Other neurogenic tumours—schwannoma, neurofibroma
    (multiple in NF1, may mimic lymphadenopathy), paraganglioma
    (hypervascular).
  7. Sarcomas—most commonly rhabdomyosarcoma. Heterogeneous,
    often with areas of necrosis, but calcification is rare (in contrast to
    neuroblastoma)
  8. Lipoblastoma—contains fat. NB: lipomas and liposarcomas are
    very rare in children.
  9. Intraabdominal pulmonary sequestration—pyramidal suprarenal
    solid-cystic mass, separate from adrenal. Has its own arterial
    supply, usually from aorta
94
Q

ABDOMINAL MASS IN A CHILD

Gastrointestinal (18%) 7

A
  1. Appendix mass/abscess (10%)—particularly spreads to pouch
    anterior to rectum.
  2. Hepatoblastoma—see Section 14.53.
  3. Haemangioma—commonly multiple, involving entire liver; may
    also involve mesentery. Large haemangiomas may bleed and
    appear heterogeneous, but shrink with time. Rarely calcify. May be
    associated with congestive heart failure and cutaneous
    haemangiomas.
  4. Choledochal cyst—the classic triad of mass, pain and jaundice is
    only present in 10%. Dynamic radionuclide scintigraphy (HIDA
    scan) is diagnostic. See Section 14.55.
  5. Enteric duplication cyst.
  6. Mesenteric cyst.
  7. Meconium pseudocyst—complication of meconium peritonitis
    in newborns, forming a rim-calcified pseudocyst in the
    peritoneal cavity. Other peritoneal calcifications may also
    be present.
95
Q

ABDOMINAL MASS IN A CHILD

Genital (4%) 3

A
  1. Ovarian cysts or teratoma.
  2. Urogenital sinus-associated cyst.
  3. Fetus in fetu—malformed parasitic fetus located inside the body
    of its viable twin.
96
Q

ABDOMINAL CYST IN A FETUS

OR NEONATE 11

A
  1. Ovarian—most common cyst in a female infant; occasionally
    cystic teratoma.
  2. Bowel—enteric duplication cyst, mesenteric/omental cysts and
    atresias.
  3. Renal—hydronephrosis (± urinoma), multicystic dysplastic kidney
    and autosomal recessive polycystic kidney disease (markedly
    enlarged kidneys + microcysts).
  4. Liver/biliary tree—choledochal cyst, hydatid cyst, mesenchymal
    hamartoma (cystic) and umbilical vein varix.
  5. Peritoneum—meconium pseudocyst.
  6. Bladder—urachal cyst and megacystis.
  7. Genital tract—urogenital sinus.
  8. Spleen—simple cyst and hydatid.
  9. Adrenal—endothelial/epithelial cysts, hydatid and following
    haemorrhage.
  10. Spine—anterior meningocoele and sacrococcygeal teratoma.
  11. Pulmonary sequestration—intraabdominal suprarenal location
97
Q

INTESTINAL OBSTRUCTION IN
A NEONATE
High intestinal obstruction - to jejunum
6

A
  1. Duodenal atresia/stenosis/web—marked dilatation of the
    proximal duodenum with the ‘double bubble’ sign, which may
    also be seen on US of the fetus (50% have a history of
    polyhydramnios). No gas distally when there is atresia, but a variable amount of gas in the distal bowel when there is stenosis.
    Duodenal web may produce a ‘windsock’ appearance as web
    balloons into distal duodenum. Bile-stained vomiting in the
    majority. Associated with annular pancreas, Down’s syndrome,
    cardiac anomalies, oesophageal atresia and other anomalies of GI
    tract. A preduodenal portal vein may be seen—this is associated
    with intrinsic duodenal obstruction (the vein is not the direct cause
    of obstruction).
  2. Malrotation and volvulus—sudden onset of bile-stained vomiting.
    Few radiological signs if the obstruction is recent, intermittent or
    incomplete. Due to its acute nature, the duodenum is not dilated.
    If not recognized, progresses to bowel ischaemia, infarction and
    death. A contrast study should show the normal C-shaped
    duodenal loop terminating to the left of the left-sided pedicle at
    the same level as the duodenal cap. In malrotation without
    volvulus the duodenojejunal flexure is abnormal, to the right of
    and below its normal position. Volvulus with incomplete
    obstruction leads to a ‘corkscrew’ jejunum. With complete
    obstruction, the distal duodenum terminates as a beak.
  3. Malrotation with obstructing Ladd’s bands—these fibrous bands
    connect the malrotated caecum to the right posterolateral
    abdominal wall and typically cross the duodenum (D2). They can
    cause obstruction even in the absence of volvulus.
  4. Jejunal atresia—constitutes 50% of small bowel atresias, and 50%
    are associated with other atretic sites distally (ileum > colon). AXR
    demonstrates three (‘triple bubble’) or more dilated, air-filled
    loops. Colon is usually normal in calibre.
  5. Pyloric atresia—rare.
  6. Pyloric or prepyloric membrane/antral web—gastric outlet
    obstruction with a normal pylorus and the appearance of two
    duodenal caps. The web may be identified by US
98
Q

INTESTINAL OBSTRUCTION IN A NEONATE

Low intestinal obstruction 9

A
  1. Meconium ileus—mottled lucencies (‘soap bubble’ appearance)
    due to gas trapped in meconium but only few fluid levels (since it
    is very viscous). Bowel loops of variable calibre. Rapid appearance
    of fluid levels suggests volvulus. Peritoneal calcification (due to
    perforation in utero) is seen in 30%. Secondary microcolon on
    contrast enema, which also shows meconium pellets in the distal
    ileum. Cystic fibrosis in the majority.
  2. Hirschsprung’s disease—multiple dilated loops of bowel.
    Diagnosis is made by contrast enema, which shows normal or
    small size of aganglionic distal bowel with a transition zone at the
    junction with proximal dilated ganglionic bowel; classically
    reversed rectosigmoid ratio. The rectum may have a serrated
    corkscrew appearance. Total colonic aganglionosis may lack a
    transition zone and present as diffuse microcolon
  3. Ileal atresia—50% of small bowel atresia, may be multiple ±
    jejunal atresia. Multiple dilated loops with fluid levels. Secondary
    microcolon.
  4. Incarcerated inguinal hernia.
  5. Small left colon syndrome (SLCS)—due to functional colonic
    immaturity; 50% associated with maternal diabetes. Small colon
    on enema up to level of splenic flexure, ± meconium plugs. Infants
    should be followed up to exclude Hirschsprung’s.
  6. Meconium plug syndrome—meconium plugs in distal colon.
    Overlaps with SLCS. May be a presenting feature of Hirschsprung’s
    or cystic fibrosis (but note this is not the same as meconium ileus).
  7. Inspissated milk—presents from 3 days to 6 weeks of age. Dense,
    amorphous intraluminal masses frequently surrounded by a rim of
    air, ± mottled lucencies internally. Usually resolves spontaneously.
  8. Colonic atresia—5%–15% of intestinal atresias. AXR may be
    similar to other distal bowel obstructions but some infants show a
    huge, disproportionately dilated loop (between the atretic segment
    and a competent ileocaecal valve).
  9. Anorectal malformation/imperforate anus.
    (a) High—± sacral agenesis/hypoplasia and gas in the bladder
    (due to a rectovesical or rectourethral fistula). Currarino triad =
    anorectal malformation, sacral dysgenesis and sacrococcygeal
    teratoma variant/meningocoele.
    (b) Low—± perineal or urethral fistula
99
Q

INTRAABDOMINAL CALCIFICATIONS IN
THE NEWBORN
5

A
  1. Meconium peritonitis—antenatal bowel perforation results in aseptic peritonitis, which rapidly calcifies. Calcification occurs in the peritoneum itself most commonly, but also in the bowel wall and in the scrotum and may be punctate, linear or plaque-like. The most common causes are meconium ileus and ileal atresia, but any cause of bowel obstruction may be associated.
  2. Meconium pseudocyst—cyst-like mass with peripheral calcification
    resulting from walling-off of extruded meconium after perforation
  3. Bowel calcification—intramural lymphatic or intraluminal meconium calcification in cases of distal bowel obstruction, particularly meconium ileus, total colonic aganglionosis and anorectal malformations. Occasionally a duodenal duplication cyst may calcify and appear as a spherical upper abdominal calcification.
  4. Hepatic calcification.
5. Adrenal calcification—following adrenal haemorrhage; rarely in 
Wolman disease (deficiency of acid lipase/acid esterase,accumulation of lipid esters in multiple tissues including the liver, spleen, lymph nodes, and small bowel)
100
Q

ABNORMALITIES OF BOWEL ROTATION 7

A
  1. Exomphalos—total failure of the bowel to return to the abdomen
    from the umbilical cord. Bowel is contained within a sac.
  2. Gastroschisis—bowel protrudes through a defect in the abdominal
    wall without a sac, classically in a right paraumbilical position.
  3. Nonrotation—usually an asymptomatic condition with the small
    bowel on the right side of the abdomen and the colon on the left
    side. Small and large bowel lie on either side of the SMA with a
    common mesentery. Imaging shows the SMV lying to the left of
    the SMA (opposite of normal arrangement).
  4. Malrotation—the duodenojejunal flexure lies to the right and
    caudad to its usual position. The caecum is usually more cephalad
    than normal, but is normally sited in 5%. Malrotation is a frequent
    feature of diaphragmatic hernia, abdominal wall defects and
    visceral heterotaxy. CT/US shows the SMV to the left of the SMA.
    A normal US does not, however, exclude malrotation (3%
    false-negative rate); upper GI contrast study remains the gold
    standard. At risk of life-threatening volvulus.
  5. Reverse rotation—rare. Colon lies dorsal to the SMA with jejunum
    and duodenum anterior to it.
  6. Paraduodenal hernia—rare.
  7. Cloacal exstrophy—rare. No rotation of the bowel, and the ileum
    and colon open separately onto the extroverted area in the midline
    below the umbilical cord. Associated with ‘open-book pelvis’ and
    split genitalia
101
Q

GAS IN THE PORTAL VEINS ( PAED)

5

A
  1. Necrotizing enterocolitis—seen in 10%. Necrotic bowel wall
    allows gas or gas-forming organisms into the portal circulation.
  2. Umbilical vein catheterization—with inadvertent injection of air.
  3. Postoperative—e.g. after liver transplant or corrective bowel
    surgery.
  4. Haemolytic disease of the newborn.
  5. Neonatal viral gastroenteritis
102
Q
HEPATIC MASSES IN CHILDREN
Malignant tumours (two-thirds) 5
A
  1. Metastases—from neuroblastoma or Wilms tumour.
  2. Hepatoblastoma—M>F, usually <5 years old (peak 18-24 months).
    Serum αFP usually raised. Typically a large well-defined
    heterogeneous mass ± vascular invasion ± areas of necrosis,
    haemorrhage and calcification. Metastasizes to lungs, abdominal
    nodes and bones. Associated with Beckwith-Wiedemann syndrome,
    hemihypertrophy and FAP.
  3. Hepatocellular carcinoma—similar features to hepatoblastoma,
    but occurs in an older age group (>5 years, peak 12-14 years with
    a smaller peak at 2-4 years), is more likely to be multifocal, and has
    a worse prognosis. Associated with chronic liver disease (cirrhosis,
    glycogen storage disease 1, tyrosinaemia, biliary atresia, chronic
    hepatitis, alpha-1 antitrypsin deficiency).
  4. Undifferentiated embryonal sarcoma of the liver—rare; majority
    are 6–10 years of age.
  5. Teratoma.
103
Q
HEPATIC MASSES IN CHILDREN
Benign tumours (one-third) 3
A
  1. Infantile hepatic haemangioma—most common benign tumour.
    Often presents in the newborn period with hepatomegaly and
    congestive cardiac failure ± skin haemangiomas (50%) ±
    consumptive coagulopathy (thrombocytopenia). Unifocal or
    multifocal, well-defined or diffuse. Typical enhancement pattern on
    CT with early peripheral enhancement + variable delayed
    centripetal filling over 30 minutes. On MRI the lesions have a
    nonspecific T1 hypointense and T2 hyperintense appearance with
    variable areas of hypointensity corresponding to fibrosis and
    haemosiderin deposition. 99mTc-labelled red cells will accumulate in this tumour. In the neonate, this and cavernous haemangioma
    may be considered together.
  2. Mesenchymal hamartoma—second most common benign
    tumour. <2 years of age. May be (multi)cystic or stromal, with a
    ‘Swiss cheese’ appearance. Solid components may enhance.
  3. Adenoma—uncommon in paediatric population. Solitary or
    multiple, occurring spontaneously or complicating glycogen
    storage disease, Fanconi anaemia treated with anabolic steroids,
    and teenagers on the oral contraceptive pill
104
Q

HEPATIC MASSES IN CHILDREN

Other lesions 3

A
  1. Cysts—simple, choledochal or hydatid.
  2. Focal nodular hyperplasia—2%–6% of hepatic lesions in
    childhood. See Chapter 8.
  3. Abscess
105
Q

FETAL OR NEONATAL LIVER
CALCIFICATION
Peritoneal surface of liver 2

A
  1. Meconium peritonitis—solid or cystic masses with calcified walls.
  2. Plastic peritonitis due to ruptured hydrometrocolpos—similar
    appearance to meconium peritonitis but US may show a dilated,
    fluid-filled uterus and vagina.
106
Q

FETAL OR NEONATAL LIVER
CALCIFICATION
Parenchymal 3

A
  1. Congenital infections—TORCH complex (toxoplasmosis, rubella,
    CMV, herpes simplex) and varicella. Randomly scattered nodular
    calcification. Often calcification elsewhere and other congenital
    abnormalities.
  2. Tumours—haemangioma, hamartoma, hepatoblastoma, teratoma
    and metastatic neuroblastoma. Complex mass on US.
  3. Haematoma—following vascular catheter injury, or haemorrhage
    in a vascular mass such as haemangioma
107
Q

FETAL OR NEONATAL LIVER
CALCIFICATION
Vascular

A
  1. Portal vein thromboemboli—subcapsular branching calcification.
  2. Ischaemic infarcts—branching calcifications but distributed
    throughout the liver
108
Q

JAUNDICE IN INFANCY

A
  1. Neonatal cholestasis—due to breastfeeding, maternal diabetes,
    drugs and total parenteral nutrition. Usually transient.
  2. Haemolytic anaemias—hereditary, ABO or Rhesus
    incompatibilities. Unconjugated hyperbilirubinaemia (unlike the
    other causes on this list).
  3. Biliary atresia—type 1 involves CBD only; type 2a involves
    CHD only; type 2b involves CHD, CBD and cystic duct; type 3
    involves all extrahepatic ducts including left and right hepatic
    ducts (>90% of cases). May be associated with congenital
    anomalies, e.g. polysplenia, intestinal malrotation, azygos
    continuation of IVC, situs inversus and preduodenal portal vein.
    On US, the ‘triangular cord’ sign (band of echogenic fibrous
    tissue at the porta hepatis replacing the bile duct) is highly
    specific. An absent or small irregular gallbladder (gallbladder
    ‘ghost’) is seen in types 2b and 3. A prominent hepatic artery
    may also support the diagnosis, but cannot be used in isolation.
    A normal-sized gallbladder that contracts after a fatty meal
    excludes the diagnosis. On HIDA scan, normal uptake by
    hepatocytes but no excretion into the bowel suggests the
    diagnosis (though alpha-1 antitrypsin may look similar). Operative
    cholangiography is definitive.
  4. Neonatal hepatitis—often idiopathic but some cases are viral
    (e.g. hepatitis A–C, rubella, CMV). Liver may be enlarged or
    hyperechoic on US, and the gallbladder may be small due to
    poor hepatocyte function. HIDA scan may show delayed
    hepatocyte uptake, but excretion into bowel is usually normal.
  5. Choledochal cyst—may present in the neonatal period or at a
    later age. See Chapter 8. On US: anechoic structure separate from
    the gallbladder, which communicates with the biliary tree. On
    HIDA scan: photopenic area, which accumulates tracer on delayed
    images. Complications include calculi, infection, pancreatitis, biliary
    cirrhosis, portal hypertension and malignancy.
  6. Alagille syndrome—hypoplasia of intrahepatic bile ducts,
    cardiovascular abnormalities (especially pulmonary stenosis),
    dysmorphic facies, eye abnormalities, butterfly vertebrae,
    radioulnar synostosis.
  7. Metabolic defects—e.g. alpha-1 antitrypsin deficiency,
    galactosaemia, tyrosinaemia and glucose-6-phosphate
    dehydrogenase enzyme deficiency
109
Q

ADRENAL MASS IN CHILDHOOD

Neoplastic 4

A

Medullary
1. Neuroblastoma, ganglioneuroblastoma, ganglioneuroma—see
Section 14.47.
2. Phaeochromocytoma—uncommon. Mean age 11 years, 25%
bilateral. Associated with MEN type 2, NF1 and vHL.
Cortical
1. Adrenocortical neoplasms—differentiating benign (adenoma)
from malignant (carcinoma) lesions not possible in childhood.
Usually hormonally active and most patients <5 years of age.
2. Malignant rhabdoid tumour—rare, highly aggressive

110
Q

ADRENAL MASS IN CHILDHOOD

Nonneoplastic—rare beyond infancy 5

A
  1. Hyperplasia—e.g. congenital adrenal hyperplasia (characteristic
    cerebriform appearance). Typically bilateral.
  2. Haemorrhage—blunt trauma, bleeding diathesis and
    meningococcal sepsis. Avascular on US.
  3. Cyst—rare, usually a lymphatic malformation or haemorrhagic
    pseudocyst.
  4. Abscess—rare; haematogenous or direct intraperitoneal spread.
  5. Calcification—Wolman disease; bilateral enlarged calcified
    adrenals
111
Q

ADRENAL MASS IN CHILDHOOD

Conditions that can mimic adrenal lesions 3

A
  1. Subdiaphragmatic extralobar pulmonary sequestration.
  2. Extramedullary hematopoiesis.
  3. Diaphragmatic lesions
112
Q

PRIMARY RENAL NEOPLASMS

IN CHILDHOOD 9

A
  1. Wilms tumour—accounts for 87% of pediatric renal masses. Peak
    incidence at 3–4 years of age, 80% present <5 years. Bilateral in
    5%. Associated abnormalities: cryptorchidism, hypospadias,
    hemihypertrophy, sporadic aniridia. Associated syndromes: Denys-Drash (Wilms tumour, male pseudohermaphroditism, progressive glomerulonephritis), WAGR ( Wilms, aniridia, GU malformations, and mental retardation) , Beckwith-Wiedemann (10% will develop
    Wilms tumour). Metastasizes to lungs and liver. 5% have a tumour
    thrombus in the IVC or right atrium. Hypertension in 25%
    (renin-induced). Screening in patients with associated syndromes
    should begin at 6 months of age, mainly by serial US every 3
    months up to 7 years of age.
    (a) Plain film—bulging flank, loss or enlargement of renal outline,
    displacement of bowel gas, loss of psoas outline, calcification
    (10%).
    (b) US—large, well-defined mass, similar or greater echogenicity
    than liver. Solid with haemorrhage/necrosis. Lack of IVC
    narrowing on inspiration suggests occlusion.
    (c) CT—large, well-defined, heterogeneous with foci of low
    attenuation necrosis. Minimal enhancement compared with
    the residual rind of functioning renal tissue. Claw sign (rim
    of preserved renal tissue clawing at the tumour mass).
    (d) MRI—heterogeneous, low T1 signal, high T2 signal.
    Inhomogeneous enhancement compared with residual
    renal tissue.
  2. Nephroblastomatosis—nephrogenic rests which maintain the
    potential for malignant induction to Wilms tumour. Seen in up to
    40% of unilateral and 99% of bilateral Wilms tumours. May be
    perilobar (most common, at the lobar surface), intralobar
    (anywhere in the cortex or medulla) or combined. Hypoechoic on
    US, similar signal to renal cortex on MRI. Nonenhancing on CT/
    MRI, therefore best seen on postcontrast images.
  3. Congenital mesoblastic nephroma—most common solid renal
    tumour in the newborn. May contain cystic, haemorrhagic or
    necrotic areas. Mean age at diagnosis is 3.5 months. Often
    indistinguishable from Wilms tumour on imaging, but different
    age group.
  4. Multilocular cystic nephroma—presents at 3 months to 4 years.
    Multiple cysts of varying size, thin septa only. May contain variable
    signal on MRI due to haemorrhage or protein content. Thick septa,
    nodules or a large solid component suggest Wilms tumour with
    cystic degeneration. Resection is curative, local recurrence is rare.
    Differential diagnosis is a multicystic dysplastic kidney, but this
    typically affects the entire kidney.
  5. Angiomyolipoma (AML)—in children, nearly always associated
    with tuberous sclerosis, and typically multiple and bilateral.
    Lesions >3 cm carry increased risk of bleeding. Surveillance with
    US or MRI is recommended 1–2 times yearly if lesions are <3 cm
    and annually if they are bigger. Characteristically contain fat on
    imaging (NB: fat may also occasionally be identified within
    Wilms tumour).
  6. Clear cell sarcoma—presents at 3–5 years. Poor prognosis with
    early metastases to bone (usually lytic but may be sclerotic). Never bilateral. Imaging features often similar to Wilms (but different
    pattern of metastases).
  7. Rhabdoid tumour of kidney—presents at 3 months to 4.5 years
    (50% in first year). Most malignant renal tumour with poorest
    prognosis. Extrarenal extension or haematogenous metastases (to
    brain or bone) often present at diagnosis. Associated with midline
    posterior cranial fossa tumours. Similar on imaging to Wilms
    tumour; however, areas of necrosis or calcification outlining
    tumour lobules may suggest rhabdoid tumour.
  8. Renal cell carcinoma—rare. Differentiating features from Wilms
    tumour are: older age (mean 11–12 years), calcification is more
    common (25%), more homogeneous, smaller at the time of
    diagnosis and haematuria is more common. Poorer prognosis
    compared with Wilms tumour. Similar imaging findings. Associated
    with von Hippel-Lindau disease and tuberous sclerosis.
  9. Ossifying renal tumour of infancy (ORTI)—rare benign tumour
    of infancy, which mimics a staghorn calculus. Presents with gross
    hematuria and a calcified mass in the pelvicalyceal system
113
Q

RENAL MASS IN THE NEWBORN AND

YOUNG INFANT 6

A
  1. Hydronephrosis—unilateral or bilateral. The most common cause
    of an abdominal mass in the first 6 months of life.
  2. Multicystic dysplastic kidney—unilateral, but 30% have an
    abnormal contralateral kidney (mostly reflux or PUJ obstruction).
    On imaging, presents as multiple cysts replacing the renal
    parenchyma with intervening fibrous tissue.
  3. Polycystic kidneys (autosomal recessive)—bilateral. Large and
    highly echogenic on US.
  4. Renal vein thrombosis—unilateral or bilateral.
  5. Renal neoplasms—e.g. congenital mesoblastic nephroma,
    multilocular cystic nephroma, rhabdoid tumour and ORTI (see
    Section 14.57).
  6. Nephroblastomatosis
114
Q

HYDRONEPHROSIS IN A CHILD 5

A
  1. PUJ obstruction—L>R, 20% bilateral. Due to stricture,
    neuromuscular incoordination or aberrant vessels. Contralateral
    kidney may be dysplastic or absent.
  2. Primary vesicoureteric reflux without obstruction—usually
    idiopathic. Common in the lower moiety of a duplex system.
  3. Vesicoureteric junction (VUJ) obstruction—may be secondary
    to bladder hypertrophy/neurogenic dysfunction or obstructive
    ureterocoele (e.g. upper moiety of a duplex kidney). Primary
    type is more common in males and on the left side. May be
    bilateral.
  4. Primary megaureter—represents ureteral atony. Sometimes
    associated with UTI; may be nonobstructive and nonrefluxing.
  5. Bladder outflow obstruction—usually due to posterior urethral
    valves (in males), causing bilateral upper tract dilatation.
115
Q

BLADDER OUTFLOW OBSTRUCTION IN

A CHILD 11

A
  1. Vesical diverticulum—posteriorly behind the bladder base. It fills
    during micturition and compresses the bladder neck and
    proximal urethra. M>F.
  2. Bladder neck obstruction—e.g. by an ectopic ureterocoele or
    rhabdomyosarcoma.
  3. Ectopic ureterocoele—80% are associated with the ectopic
    upper moiety ureter of a duplex kidney. 15% are bilateral. F>M.
    Ectopic ureter may open into the urethra, bladder neck or
    vestibule. Ureterocoele may be largely outside the bladder,
    elevating the bladder base, or may prolapse into the urethra 4. Posterior urethral valves—on MCUG, posterior urethra is dilated
    and the distal urethra is small. Almost exclusively males.
  4. Urethral stricture—posttraumatic strictures (e.g. instrumentation
    or catheterization) are most commonly at the penoscrotal
    junction.
  5. Cowper’s syringocoele—dilatation of the main duct of the
    bulbourethral (Cowper’s) glands; males only. Filling of Cowper’s
    ducts may be a normal finding. When dilated, occasionally
    presents with haematuria, infection or urethral obstruction.
  6. Anterior urethral diverticulum/valve—a saccular wide-necked,
    ventral expansion of the anterior urethra, usually at the
    penoscrotal junction. The proximal lip of the diverticulum may
    show as an arcuate filling defect and during micturition the
    diverticulum expands with urine and obstructs the urethra.
  7. Prune-belly and megacystis-microcolon syndromes.
  8. Calculus or foreign body.
  9. Meatal stenosis—males only; usually a clinical diagnosis, but
    may be detected on MCUG; voiding images should include the
    meatus (external urethral opening).
  10. Phimosis—clinical diagnosis
116
Q

VESICOURETERIC REFLUX

Congenital = primary reflux 2

A
  1. Simple congenital reflux—due to VUJ incompetence secondary to
    abnormal tunnelling of distal ureter through bladder. 10% of
    normal Caucasian babies and 30% of children with a first episode
    of UTI. Usually disappears in 80%. Medium- to high-grade reflux
    can lead to renal damage in association with UTI.
  2. Reflux associated with duplex kidneys—usually occurs into
    lower-moiety ureter, which has a normal position but abnormal
    tunnelling. Reflux may also occur into a ureterocoele if this everts
    during filling or voiding
117
Q

VESICOURETERIC REFLUX

Acquired = secondary reflux 5

A
  1. Hutch diverticulum—congenital bladder diverticulum at the VUJ.
  2. Cystitis—in 50%.
  3. Neurogenic bladder.
  4. Urethral obstruction—most commonly posterior urethral valves
  5. Prune-belly syndrome—almost exclusively males. High mortality.
    Bilateral hydronephrosis and hydroureters with a distended
    bladder. Associated with undescended testes, hypoplasia of the
    anterior abdominal wall and urethral obstruction.
118
Q

RETINOBLASTOMA AND

ITS DIFFERENTIALS

A

Rare but most common intraocular tumour of childhood; usually presents <5 years. An aggressive malignant tumour, accounts for ~10% of all cancers in the first year of life. Bilateral or multifocal tumours occur in patients with heritable retinoblastoma (~30–60% of cases). If bilateral heritable retinoblastomas occur with a
primary intracranial neuroblastic tumour (usually pineal or parasellar), the syndrome is called ‘trilateral retinoblastoma’.
Leukocoria and strabismus are the most common presenting symptoms.

Differential diagnosis of retinoblastoma
Greater than 50% of children presenting with a clinical diagnosis
of retinoblastoma have another diagnosis, commonly persistent
hyperplastic primary vitreous (PHPV), Coat’s disease or
toxocariasis. Calcification (95% on CT) is the most important
feature that differentiates retinoblastoma from other tumour-like
lesions. None of the conditions in the following table show
calcification <3 years, but above that age some may do so, e.g.
retinal astrocytoma, retinopathy of prematurity and toxocariasis.

119
Q

Coat’s disease

A

A vascular anomaly of telangiectatic vessels, which leak proteinaceous material into the subretinal space. Usually boys; unilateral. Present at birth but usually asymptomatic until the retina detaches and vision deteriorates.

120
Q

PREVERTEBRAL SOFT-TISSUE MASS ON

THE LATERAL CERVICAL X-RAY 3

A
  1. Trauma/haematoma—± associated fracture.
  2. Abscess—± gas lucencies within it. Unlike the normal variant
    described above, these lucencies are constant and persist during
    deep inspiration. A sharp foreign body may be visible within the
    collection.
  3. Neoplasms—e.g. lymphangioma, lymphoma, nasopharyngeal
    rhabdomyosarcoma, neuroblastoma and LCH (with vertebra
    plana)
121
Q

NECK MASSES IN INFANTS
AND CHILDREN
Congenital 3

A
  1. Lymphovascular malformations—soft. Lymphangiomas are
    uni- or multilocular and often involve multiple neck spaces.
    Infantile haemangiomas are solid and hypervascular, and typically
    resolve spontaneously.
  2. Cysts—firm.
    (a) Thyroglossal—midline position.
    (b) Branchial cleft—lateral position. Second branchial arch
    remnant most common, lying posterior to the submandibular
    gland, lateral to the carotid space and anteromedial to the
    sternomastoid muscle.
    (c) Lingual—including ranula.
    (d) Thymic—rare, remnant of thymopharyngeal duct. Located
    close to carotid sheath, often extends into mediastinum.
    (e) Dermoid/epidermoid/teratoma—midline, often contains fat
    and calcification (except epidermoid, which only contains
    fluid).
  3. Ectopic cervical thymic lobe
122
Q

NECK MASSES IN INFANTS
AND CHILDREN
Acquired 7

A
  1. Infective/reactive lymphadenopathy—e.g. viral, bacterial,
    mycobacterial and cat-scratch disease. Nonviral nodal infections
    can lead to suppuration/abscess formation.
  2. Malignant neoplasms—e.g. lymphoma, neuroblastoma
    (secondary > primary), rhabdomyosarcoma, LCH (disseminated
    disease in infants) and thyroid cancer (rare, usually papillary).
  3. Benign neoplasms—e.g. lipoma, neurofibroma (in NF1),
    pilomatricoma (arises from skin, often calcified), thyroid cyst or
    nodule.
  4. Fibromatosis colli—unilateral enlargement of sternocleidomastoid
    muscle in young infants ± torticollis. Thought to be related to birth
    trauma.
  5. Trauma/haematoma.
  6. Diffuse thyroid enlargement—e.g. Graves’ disease, multinodular
    goitre and Hashimoto’s thyroiditis.
  7. Parotitis—e.g. bacterial (unilateral), HIV (bilateral) and Sjögren’s
    (bilateral)
123
Q

CAUSES OF STROKE IN CHILDREN AND

YOUNG ADULTS 7

A
  1. Emboli—cyanotic heart disease (due to R→L intracardiac shunt),
    cardiomyopathies, mitral valve prolapse, HHT (due to pulmonary
    AVMs).
  2. Arterial wall abnormalities.
    (a) Dissection—may be traumatic (including nonaccidental injury), spontaneous, or secondary to Marfan syndrome, Ehlers-Danlos syndrome or homocystinuria.
    (b) Vasculitis/vasculopathy—e.g. due to Moyamoya disease, fibromuscular dysplasia (also vessel stenoses and saccular dilatations, intracranial aneurysms), NF1, Kawasaki, SLE and sarcoidosis.
    (c) Reversible cerebral vasoconstriction syndrome—due to vasospasm, presents with ‘thunderclap’ headache (adolescents > children). Can cause watershed infarcts. Associated with pregnancy (including preeclampsia and
    puerperium) , drugs (e.g. cocaine and amphetamines) and migraine.
  3. Cerebral venous sinus thrombosis—pregnancy, postpartum, oral
    contraceptive pill, skull base/intracranial sepsis, IBD, SLE, Behçet’s
    disease and malignancy
  4. Infection—purulent meningitis may cause arterial and venous strokes. Viral infection can cause a vasculitis, usually of the proximal MCA, leading to infarction of the basal ganglia with sparing of the cortical territories.
  5. Blood disorders—sickle cell anaemia, polycythaemia, protein C and S deficiency and antiphospholipid syndrome.
  6. MELAS—Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episodes.
  7. Idiopathic—in many cases, a cause is not found
124
Q

LARGE HEAD IN INFANCY 11

A
  1. Benign familial macrocephaly—usually associated with parental
    large head and large head circumference at birth.
  2. Benign enlargement of subarachnoid space (BESS)—also
    called ‘external hydrocephalus’. Benign, self-limiting. Increased
    risk of subdural haematoma either spontaneously or after minor
    accidental trauma, which may mimic nonaccidental injury.
  3. Hydrocephalus.
  4. Chronic subdural haematoma.
  5. Brain tumours.
  6. Neurofibromatosis* type 1.
  7. Mucopolysaccharidoses*.
  8. Hemimegalencephaly.
  9. Leukodystrophy.
    (a) Alexander’s disease—typically involves the frontal lobes
    early in its course.
    (b) Canavan’s disease—typically affects the subcortical arcuate
    fibres, but often involves the entire cerebral white matter.
  10. Overgrowth syndromes—e.g. Sotos, Simpson-Golabi-Behmel,
    Beckwith-Wiedemann.
  11. Hydranencephaly
125
Q

WIDE CRANIAL SUTURES
>10 mm at birth; >3 mm at 2 years; >2 mm at 3 years
5

A
  1. Raised intracranial pressure—e.g. due to intracranial tumour,
    subdural haematoma or hydrocephalus. Only seen in children
    <10 years
  2. Infiltration of sutures—e.g. by neuroblastoma (± skull vault
    lucencies and ‘sunray’ spiculation), leukaemia or lymphoma.
  3. Metabolic disease—rickets, hypoparathyroidism, lead toxicity or
    bone dysplasias with defective mineralization (e.g.
    hypophosphatasia).
  4. Traumatic diastasis of the sutures.
  5. Recovery from illness—rapid rebound growth of the brain
    following chronic illness, deprivational dwarfism, prematurity or
    hypothyroidism
126
Q

MULTIPLE WORMIAN BONES 14

A
  1. Idiopathic.
  2. Down’s syndrome*.
  3. Pyknodysostosis.
  4. Osteogenesis imperfecta.
  5. Rickets*.
  6. Cleidocranial dysplasia*.
  7. Kinky hair (Menkes) syndrome.
  8. Hypophosphatasia.
  9. Hypothyroidism.
  10. Otopalatodigital syndrome.
  11. Primary acroosteolysis (Hajdu-Cheney syndrome).
  12. Pachydermoperiostosis.
  13. Gerodermia osteodysplastica—see Section 14.12.
  14. Progeria.
127
Q

CRANIOSYNOSTOSIS

Primary craniosynostosis 7

A
  1. Sagittal synostosis—elongated narrow ‘boat-shaped’ skull
    (scaphocephaly).
  2. Unilateral coronal synostosis—oblique appearance of the
    craniofacial structures (frontal plagiocephaly) with harlequin orbit.
  3. Bilateral coronal synostosis—‘short head’ (brachycephaly), often
    seen with synostosis of other sutures.
  4. Metopic synostosis—triangular-shaped head (trigonocephaly) with
    orbital hypotelorism.
  5. Unilateral lambdoid synostosis—asymmetric occipital
    plagiocephaly.
  6. Bilateral lambdoid synostosis—occipital plagiocephaly with
    flattened occiput. Beware postural flattening of the occiput due to
    infants being placed to sleep on their backs (no sutural fusion in
    these cases).
  7. Cloverleaf skull—‘trilobular skull’ due to synostosis of multiple
    paired sutures
128
Q

CRANIOSYNOSTOSIS

Syndromic craniosynostosis

A

Most commonly seen in acrocephalosyndactylies (e.g. Apert,
Carpenter and Pfeiffer syndromes). Each syndrome exhibits
synostosis of multiple sutures with severe calvarial and facial
malformations. Crouzon syndrome differs in that there is no
syndactyly

129
Q

CRANIOSYNOSTOSIS

Secondary 5

A
  1. Brain damage or malformation—following hypoxic ischaemic
    encephalopathy, holoprosencephaly, microcephaly.
  2. Iatrogenic—shunted hydrocephalus.
  3. Metabolic—rickets, hyperthyroidism, hypophosphatasia.
  4. Inborn errors of metabolism—Hurler and Morquio syndromes.
  5. Haematological disease—thalassaemia and sickle cell.
130
Q

CYSTIC LESIONS ON CRANIAL US IN
NEONATES AND INFANTS
Normal variants 2

A
  1. Coarctation of the lateral ventricles—aka connatal cysts: small
    cysts at the superolateral margin of the frontal horns.
  2. Cavum septum pellucidum/vergae/velum interpositum—
    common, particularly in premature neonates
131
Q

CYSTIC LESIONS ON CRANIAL US IN
NEONATES AND INFANTS
Infratentorial cysts 3

A
  1. Mega cisterna magna—as an isolated finding, probably a normal
    variant. Intact vermis.
  2. Dandy-Walker malformation/variant—vermian hypoplasia +
    cystic dilatation of posterior fossa in communication with the
    fourth ventricle.
  3. Arachnoid cyst—one-quarter occur in the posterior fossa, most
    commonly retrocerebellar
132
Q

CYSTIC LESIONS ON CRANIAL US IN
NEONATES AND INFANTS
Supratentorial cysts 6

A
  1. Subependymal cysts—located in subependymal region around
    the caudothalamic notch. Most commonly represent previous
    germinal matrix haemorrhage. May be congenital, probably
    reflecting germinolysis, particularly in association with CMV
    infection.
  2. Choroid plexus cysts—usually located within body of choroid
    plexus. Weak markers of aneuploidy, particularly if large and
    bilateral. No clinical significance if detected after birth.
  3. Cystic periventricular leukomalacia—white matter necrosis in
    preterm infant. Hyperechoic lesions dorsal and lateral to external
    angles of lateral ventricles, developing into cysts in severe cases.
  4. Porencephalic cyst—an area of cystic encephalomalacia filled with
    CSF, often following haemorrhage or infection, communicating
    with the ventricular system.
  5. Arachnoid cyst—most commonly in the sylvian fissure, usually
    incidental. Suprasellar cysts are more frequently symptomatic.
  6. Vein of Galen malformation—not a cyst, but may appear so on
    US. Colour Doppler flow confirms.
133
Q

DISORDERS OF NEURONAL MIGRATION

5

A
  1. Agyria-pachygyria—poorly formed gyri and sulci, the former
    being more severe. Focal pachygyria may cause focal epilepsy.
    Polymicrogyria may coexist with pachygyria. Pachygyria may also be seen in Zellweger syndrome (germinolytic cysts, polymicrogyria in perisylvian, frontal pachygyria) and prenatal CMV infection.
    Extreme cases with a smooth brain = lissencephaly. Complete
    lissencephaly = agyria. Several distinct forms.
    (a) Type I lissencephaly—small brain with few gyri; smooth,
    thickened four-layer cortex resembling that of a 13-week fetus
    with diminished white matter and shallow vertical sylvian
    fissures (‘figure-of-eight’ appearance on axial images) ±
    agenesis of corpus callosum. Severe mental retardation,
    diplegia, seizures, microcephaly and limited survival. Some
    infants have specific dysmorphic features: Miller-Dieker
    syndrome and Norman-Roberts syndrome.
    (b) Type II lissencephaly (Walker-Warburg syndrome)—smooth
    cobblestone cortex, cerebellar hypoplasia, vermian aplasia and
    hydrocephalus (in 75%) due to cisternal obstruction by
    abnormal meninges or aqueduct stenosis. Eye abnormalities
    including microphthalmia and buphthalmos (enlarged globe) due to increased
    pressure and cataract.
  2. Polymicrogyria—the neurons reach the cortex but are distributed
    abnormally. Macroscopically the surface of the brain appears as
    multiple small bumps. Localized abnormalities are more common
    than generalized and often involve arterial territories, especially the
    MCA. Most common location is around the sylvian fissure. The
    cortex is isointense to grey matter but in 20% the underlying
    white matter has high T2 signal. Linear flow voids, due to
    anomalous venous drainage, may be present. Polymicrogyria may
    be present in the vicinity of a porencephalic cyst, and may be
    associated with heterotopic grey matter, agenesis of corpus
    callosum or signs of fetal infection (e.g. intracranial calcification).
    The majority have mental retardation, seizures and neurological
    signs.
  3. Schizencephaly—clefts that extend through the full thickness of
    the cerebral mantle from ventricle to subarachnoid space. The cleft
    is lined by heterotopic grey matter and microgyria, indicating that
    it existed prior to the end of neuronal migration. Unilateral or
    bilateral (usually asymmetrical) and usually near the sylvian fissure.
    May be associated with absence of the septum pellucidum or, less
    commonly, dysgenesis of the corpus callosum. Variable clinical
    manifestations, from profound retardation to isolated partial
    seizures.
  4. Heterotopic grey matter—collections of neurons in a
    subependymal location, i.e. at the site of the germinal matrix or
    arrested within the white matter on their way to the cortex.
    Isointense to normal grey matter on all imaging sequences.
    Nodules or bands, ± mass effect. Often a part of complex
    malformation syndromes, or when isolated, may be responsible for
    focal seizures (amenable to surgical treatment)
  5. Cortical dysplasia—focal disorganization of the cerebral cortex. A
    single enlarged gyrus resembling focal pachygyria. Usual
    presentation is with partial epilepsy.
134
Q

SUPRATENTORIAL TUMOURS

IN CHILDHOOD 10

A
  1. Hemispheric astrocytoma—solid ± necrotic centre, or cystic with
    a mural nodule. Usually large at presentation and can involve
    basal ganglia and thalami. Most are low grade. Enhancement
    with contrast medium does not correlate with histological grade.
    Associated with NF1.
  2. Craniopharyngioma—>50% of all craniopharyngiomas occur in
    children (8–14 years). Cystic/solid partially calcified suprasellar
    mass presenting with headache, visual disturbance and endocrine
    abnormalities.
  3. Optic pathway glioma—low grade but infiltrative pilocytic
    astrocytomas associated with NF1. Solid enhancing tumours that
    extend along the length of the anterior optic pathways and may
    invade adjacent structures (e.g. hypothalamus) and extend
    posteriorly into the optic tracts and radiations.
  4. Giant cell subependymal astrocytoma—occurs in tuberous
    sclerosis; slow-growing partially cystic, partially calcified tumour
    located at the foramen of Monro. Presents with obstructive
    hydrocephalus.
  5. Germ cell tumours—germinoma and teratoma.
  6. Primitive neuroectodermal tumour (PNET)—large
    heterogeneous hemispheric mass presenting in neonates and
    infants. Necrosis, haemorrhage and enhancement are common.
  7. Dysembryoplastic neuroepithelial tumour (DNET)—benign
    cortical tumour often presenting with seizures. Cortical
    (temporal) mass, usually small ± internal cysts and calcification.
  8. Ganglioglioma—well-defined peripheral tumour that often
    presents with seizures. Cystic tumour with mural nodule ±
    calcification.
  9. Choroid plexus papilloma—presents in young children with
    hydrocephalus. Most occur in the atrium of the lateral ventricle
    (fourth ventricle in adults) and appear as a well-defined multilobulated avidly enhancing intraventricular mass ±
    calcification. Invasion of brain suggests choroid plexus
    carcinoma.
  10. Ependymoma—often in the frontal lobe adjacent to the frontal
    horn, but not usually intraventricular
135
Q

INFRATENTORIAL TUMOURS

IN CHILDHOOD 5

A
  1. Cerebellar astrocytoma—most common posterior fossa tumour in
    children ≥5 years. Vermis (50%), hemispheres (20%) or both
    (30%). Calcification in 20%. Large mass displacing (or invading)
    the fourth ventricle. 80% are juvenile pilocytic astrocytomas with
    an excellent prognosis. 50% are cystic with an enhancing mural
    nodule. 40% are solid with central necrosis. 10% are purely solid
    (usually smaller than the other types). Usually no restricted
    diffusion.
  2. Medulloblastoma—most common posterior fossa tumour in
    children <5 years. Short history (aggressive). 80% located in the
    vermis, often extending into the fourth ventricle through its roof;
    30% extend into the brainstem. Moderately well-defined mass,
    slightly hyperdense to surrounding cerebellum on CT + rim of
    oedema. Calcification in 10%. Small cystic or necrotic areas can be
    seen. Variable enhancement. Heterogeneous T2 signal on MRI.
    Marked restricted diffusion is typical. Tumour disseminates through
    CSF into the subarachnoid space (including spinal canal) and
    ventricular system. Extracranial metastases to bone, lymph nodes
    or soft tissues.
  3. Ependymoma—15% of posterior fossa tumours. Usually a long
    clinical history. Most commonly arises from the floor of the fourth
    ventricle. On CT, typically an iso- or hyperdense mass with
    punctate calcifications, small cysts and heterogeneous
    enhancement. Calcification in a fourth ventricular mass or adjacent
    to the fourth ventricle = ependymoma. Heterogeneous on MRI,
    with less restricted diffusion than medulloblastoma. Tumour
    extension through the foramina of Luschka or Magendie is
    characteristic.
  4. Brainstem glioma—insidious onset because of its location and
    tendency to infiltrate cranial nerve nuclei and long tracts without
    producing CSF obstruction until late. Four subgroups: medullary,
    pontine (most common), mesencephalic and those associated with
    NF1 (slower progression). Tumours may also be diffuse (>50%–
    75% of the brainstem in the axial plane, most common in pons)
    or focal (<50%, most common in tectal plate). Calcification rare.
    Typically T2 hyperintense on MRI, with no/minimal restricted
    diffusion or enhancement.
  5. Atypical teratoid/rhabdoid tumour (ATRT)—rare but aggressive,
    with high potential for CNS dissemination. Usually in children <3
    years. On MRI, ATRT often shows heterogeneous signal with
    diffusion restriction, similar to medulloblastoma, but has a higher
    propensity for calcification (~50%), haemorrhage, necrosis and
    cystic change.
136
Q

INTRAVENTRICULAR MASS IN CHILDREN

Solid mass Lateral ventricles 11

A
  1. Choroid plexus papilloma/carcinoma—see Section 14.72.
  2. Astrocytomas—usually arise from subependymal tissue and
    protrude into ventricle.
  3. Ependymoma—less common than in fourth ventricle.
  4. Primitive neuroectodermal tumour—see Section 14.72.
  5. Meningioma—rare in children except in NF2.
  6. Choroid plexus enlargement—NF1, Sturge-Weber.
  7. Teratoma.
  8. Arteriovenous malformation—enlarged draining veins.
  9. Subependymal heterotopia—nodules of ectopic grey matter.
  10. Metastatic seeding—e.g. medulloblastoma, ependymoma.
  11. ATRT - atypical teratoid/rhabdoid tumour
137
Q

IINTRAVENTRICULAR MASS IN CHILDREN

Solid mass Foramen of Monro 2

A
  1. Subependymal giant cell astrocytoma—see Section 14.72.
  2. Central neurocytoma—well-defined heterogeneous mass arising
    from septum pellucidum close to foramen of Monro. Often
    contains calcification and cystic change.
138
Q

INTRAVENTRICULAR MASS IN CHILDREN

Solid mass Third ventricle 7

A
  1. Craniopharyngioma—arises from the suprasellar region (see
    Section 14.72); may mimic a third ventricle mass if large.
  2. Glioma—hypothalamic or chiasmatic pilocytic astrocytomas.
  3. Germinoma—pineal or suprasellar; see Chapter 13.
  4. Teratoma—usually posterior, in the pineal region.
  5. Langerhans cell histiocytosis*—arises from the floor of the third
    ventricle or suprasellar region.
  6. Choroid plexus papilloma—see Section 14.72.
  7. Metastatic seeding
139
Q

INTRAVENTRICULAR MASS IN CHILDREN

Solid mass Fourth ventricle 5

A
  1. Medulloblastoma—see Section 14.73.
  2. Ependymoma—see Section 14.73.
  3. Choroid plexus papilloma—see Section 14.72.
  4. Exophytic brainstem/cerebellar glioma—see Section 14.73.
  5. ATRT
140
Q

INTRAVENTRICULAR MASS IN CHILDREN

Cystic mass 5

A
  1. Choroid plexus cyst/xanthogranuloma—typically in the trigone
    of the lateral ventricles, often bilateral. Usually incidental.
  2. Colloid cyst—characteristic location in the anterosuperior aspect of
    the third ventricle, close to the foramina of Monro ± obstructive
    hydrocephalus. Typically contains proteinaceous material,
    appearing hyperdense on unenhanced CT and causing variable
    (but homogeneous) T1 and T2 signal on MRI. No enhancement.
  3. Intraventricular simple cysts—e.g. ependymal cyst, arachnoid
    cyst. Follows CSF on all MRI sequences, thin/imperceptible wall
    and no enhancement. Distorts ventricle outline when large (may
    be the only sign of its presence).
  4. Cysticercosis*—appearance varies depending on stage. Often
    causes ventriculitis leading to aqueduct stenosis and
    hydrocephalus.
  5. Hydatid cyst—rare