Fetal Head/face/neck

Question 1

Anencephaly

Answer 1

No Brain,skull
Frog like face appearance
MOST COMMON NTD

Question 2

Acrania (aka. Exencephaly)

Answer 2

No skull bones with presents of brain

Question 3

Cephalocele

Answer 3

Protrusion of the meninges and/or brain through a defect in the cranium.
Most most often seen in the occipital region (80%)

Question 4

Meningocele

Answer 4

Protrusion of the meninges (cystic looking)

Cephalocele

Question 5

Encephalocele

Answer 5

Protrusion of brain tissue - complex structure

Cephalocele

Question 6

Meningoencephalocele

Answer 6

Meninges and brain tissue - complex

Cephalocele

Question 7

Meningoencephalocele

Answer 7

Protrusion of Meninges, brain tissue and ventricle - Complex

Cephalocele

Question 8

Iniencephaly

Answer 8

Defect in the occiput, usually involves the foramen magnum.

-Retroflexion of the fetal head STAR GAZER

Question 9

Spina Bifida>

• Meningocele
• Meningomyelocele
• Open V.s. Close

Answer 9

Failure of the two halves of the vertebral arch to fuse. *73% lumbosacral region)

• Meningocele = Herniation of meninges (cystic on US)
• Meningomyelocele = meninges and spinal cord (complex cystic mass on US)
• Open = open wound
• Closed = Closed wound

Question 10

Spina bifida on US

Answer 10

In transverse = splaying of the posterior ossification centers with V or a U configuration
In sag= “train track” will come to a stop

Question 11

Cranial findings associated with spina bifida

Answer 11

~Lemon sign – anterior calvarium collapse (frontal)
~Banana sign – obliteration of the cisterna magna by cerebellum
~Ventriculomegaly- block of spinal fluid flow

Question 12

Arnold-Chiari Malformation

Answer 12

Defects in the cerebellum and brainstem. A part of the cerebellum is located below the foramen magnum (normally located above the foramen magnum).

Question 13

Arnold-Chiari Malformations Type 2

Answer 13

Associated with spina bifida, characterized by displacement of the cerebellum, brain stem, fourth ventricle, pons and medulla oblongata through the foramen magnum.

This is usually associated with hydrocephalus and meningomyelocele. (Cerebellum = banana (loss of dumbbell shape) Lemon (head resemble lemon), ventriculomegaly is seen.

Question 14

Associated with Arnold-Chiari 2

Answer 14

Spina Bifida 80-90%

Trisomy 18

Question 15

Dandy-walker

Answer 15

• Agenesis of cerebellar vermis( Large midline cystic structure in posterior fossa).

Question 16

Dandy-Walker malformation

Answer 16

• *MOST SEVERE**
• Complete/partial agenesis of cerebeller vermis
• Dilation of fourth ventricle

Question 17

Dandy-Walker variant

Answer 17

Partial agenesis of cerebellar vermis
Normal forth ventricle
Key hole

Question 18

Posterior Fossa Arachnoid Cyst

Answer 18

• Collection of CSF enclosed within the layers of the arachnoid that can displace adjacent normal brain parenchyma.
• *Does not communicate with ventricles or subarachnoid spaces**

Question 19

Holoprosencephaly

Answer 19

BRAIN & FACE
Trisomy 13
ALOBAR - most severe
Several abnormalities of the brain and face resulting from incomplete cleavage (division) of the primitive prosencephalon portion of the brain (forebrain)

Question 20

Agenesis of the Corpus callosum

Answer 20

> DX before 20 wk may be difficult

> Sonographic appearance:

- Teardrop- shaped ventricle
- Absent cavum septi pellucidi
- Sunburst appearance of gyri and sulci

Question 21

Aqueductal Stenosis

Answer 21

> Obstruction, atresia, or stenosis of the aqueduct of sylvius causing ventriculomegaly.

> Sonographic appearance
Enlargement of the lateran ventricles and third ventricle in the presence of a normal forth ventricle.

Question 22

Vein of Galen Aneurysm- (AKA- A vein of Galen malformation)

Answer 22

> Rare AVM
• Cystic space that may appear irregular in shape and is located midline and posteriorsupesior to the third ventricle.
• Turbulent flow with color doppler evaluation

Question 23

Choroid plexus cyst

Answer 23

> Should resolve between 22-26 wks
Benign if no other anomalies found
Associated with Trisomy 18

Question 24

Porencephaly- (AKA Porencephalic cysts)

Answer 24

> Single of multiple cystic masses in the brain

> Communicate with the ventricular system of the subarachnoid space

Question 25

Hydranencephaly

Answer 25

> Water, No brain | > Destruction of the Cerebral hemispheres replaced with CSF by the **occlusion of the internal carotid arteries**.

Question 26

Schizencephaly

Answer 26

> Rare malformation by abnormal clefts in the cerebral hemispheres **Splits brain into anterior and posterior parts**

Question 27

Lissencephaly

Answer 27

> The surface lacks the normal sulci and gyri, and appears smooth. > DX can not be made until the 3rd trimester

Question 28

Ventriculomegaly --&-- Hydrocephalus

Answer 28

Ventriculomegaly - Increase in CSF in ventricles, Lateral ventricle >10mm, Main cause aqueductal stenosis Hydrocephalus - ^ with enlargement of fetal head

Question 29

Microcephaly

Answer 29

Small head circumference, 3 standard deviations below normal.

Question 30

Skull shapes; 1. Clover-leaf 2. Lemon-shaped 3. Strawberry-shaped

Answer 30

1. Clover-leaf - Dwarfism 2. Lemon-shaped - Seen often with banana shaped cerebellum due to open NTD, Arnold-Chiari 2, spina bifida 3. Strawberry-shaped - Trisomy 18

Question 31

Frontonasal Dysplasia

Answer 31

Facial defect affecting midline of face. | -Midline cleft lip/palate-

Question 32

Cleft Lips/Palates

Answer 32

- Most common - US appearance of Cleft Lip/Palate • Large gap in upper lip seen on coronal view of lip and nose • Mass effect formed by the upper lip bulging forward • Nose is usually flattened & widened

Question 33

Midline cleft lip/palate

Answer 33

-Frontonasal Dysplasia The face predicts the brain Search for coexisting brain anomalies

Question 34

Profile: * Absent/flattened nasal bone – * Forehead/Frontal bone - * Enlarged tongue – * Chin – Microgenathia (undersized jaw) * Epignathus. –

Answer 34

* Absent/flattened nasal bone – Trisomy 21 * Forehead/Frontal bone - slopping or bossing * Enlarged tongue – Macroglassia, Beckwith-Wiedemann syndrome * Chin – Microgenathia (undersized jaw). – chromosomal anomalies * Epignathus. – a teratoma arising from the oral/nasal cavity of pharynx

Question 35

Orbits: * Anopthalmis – * Micropthalmia – * Hypotelorism – * Hypertelorism. – *Dacryocystocele –

Answer 35

* Anopthalmis – Absent eye of eyes * Micropthalmia – Small eyes * Hypotelorism –decrease distance between eyes * Hypertelorism. – increased distance between eyes *Dacryocystocele – Protrusion of the lacrimal sac

Question 36

Neck: * Nuchal Translucency * Nuchal fold * Cystic hygroma * Fetal thyroid goiter

Answer 36

* Nuchal Translucency - Abnormal >3mm, measured between 11-14wks * Nuchal fold - Abnormal >6mm, measured between 15-21wks, Associated with Trisomy 21 * Cystic hygroma- Lymphatic obstruction, Cystic, single/multiloculated fluid filled cavity, Posterior &/or lateral aspect of fetal neck, associated with Trisomy 21, Turners’s * Fetal thyroid goiter - Solid appearing mass, anteriorly located