Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Greenberg > 15 Primary intracranial anomalies > Flashcards

15 Primary intracranial anomalies Flashcards

1
Q

Commonest location for arachnoid cysts?

A

Middle cranial fossa (related to sylvian fissure in 49% of cases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do arachnoid cysts occur?

A

Congenital lesions that occur during development from splitting of the arachnoid membranes.

Therefore contain fluid that is identical to CSF, is intra-arachnoid and does not communicate with ventricle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What cells line the wall of an arachnoid cyst?

A

Meningothelial cells - +ve for EMA (Epithelial membrane antigen) and -ve for CEA (carcinoembryonic antigen)

May also be ‘complex’ and contain neuroglia, ependymal and other tissue types

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the incidence of arachnoid cysts?

A

On autopsy series found to be 5 per 1000

1% of intracranial masses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In which condition might you see bilateral arachnoid cysts?

A

Hurler’s syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do you classify middle fossa cysts?

A

Galassi classification (1983)

Type 1. binconvex anterior middle-fossa. No/minimal mass effect. Communicates with subarachnoid spaces on CT with water soluble contrast.

Type 2. Rectangular shaped, in connection with anterior and intermediate sylvian fissure. Partially communicates with subarachnoid spaces on CT + WSC

Type 3. Involves whole sylvian fissure, mass effect and midline shift with bony remodelling. Minimal communication with subarachnoid space.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the surgical treatment options for arachnoid cyst?

A

needle aspiration/burr hole drainage
craniotomy and excising/fenestrating cyst walls into cisterns
endoscopic fenestration
shunting of cyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which type of arachnoid cyst should not be shunted?

A

suprasellar cysts - (promotes cyst enlargement)
Can be managed surgically with transcallosal approach or transventricular endoscopic approach. (Pierre-Khan et al)
Endocrinopathies tend to persist.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What proportion of single suture craniosynostosis have elevated ICP?

A

approx 11% (no ref)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What head shape does saggital synostosis cause?

A

scaphocephaly / dolichocephaly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What causes trigonocephaly?

A

metopic suture synostosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do you tell the difference between lambdoid suture synostosis causing posterior plagiocephaly and positional plagiocephaly?

A 
Head shape (trapezius shape in lambdoid and parallelogram in positional)
Ear position (pulled back in lambdoid and pushed forward/neutral in positional)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the incidence of craniosynostosis?

A

0.6/1000 live births

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What percentage of non-syndromic saggital suture synostosis have raised ICP?

A

44%

Ref: Wall et al. 2014

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the commonest single suture craniosynostosis?

A

Saggital suture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is ‘Harlequin eye’?

A

Seen in coronal synostosis on Xray on the abnormal side because of the higher orbital bar. Can cause amblyopia as well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the incidence of craniosynostosis?

A

0.6 per 1000 live births

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Single suture craniosynostosis that can cause ambylopia?

A

Coronal suture

19
Q

What causes trigonocephaly?

A

Metopic suture synostosis

20
Q

What deformity does saggital suture synostosis cause?

A

scaphocephaly/dolichocephaly

21
Q

How can you differentiate between postural plagiocephaly and posterior plagiocephaly due to do lambdoid synostosis?

A

Ear position

head shape

22
Q

What proportion of patients with saggital suture synostosis have raised ICP?

A

44%

ref Wall et al 2014

23
Q

What is the difference in phenotype between Aperts and Crouzons?

A

Aperts have syndactyly

24
Q

What is Harlequin’s eye sign?

A

X-ray finding in unilateral coronal synostosis. Seen on the normal side as eye gets pulled up.

25
Q

Craniosynostosis associated with 19p chromosome abnormality

A

Metopic synostosis

26
Q

Which suture synostosis can be felt as an indentation rather than ridge?

A

Lambdoid

27
Q

What is the pattern of inheritance (and which gene) is implicated in Crouzon and Aperts?

A

FGFR (fibroblast growth factor receptor) gene
Autosomal dominant
Can be sporadic (more likely in Aperts)

28
Q

Nasal polypoid mass in newborn - what is the diagnosis?

A

Encephalocoele until proven otherwise

29
Q

How are encephalocoeles classified?

A

On location, based on system by Suwanwela and Suwanwela.

  1. Occipital (often involves vascular structures)
  2. Cranial Vault
  3. fronto-ethmoidal - through the face
  4. basal
  5. post fossa
30
Q

What is the eitiology of encephalocoeles?

A

two main theories:

arrested closure of normal confining tissue allows herniation through persistent defect
early outgrowth of neural tissue prevents normal closure of cranial coverings

31
Q

How do basal encephalocoeles present?

A

Persistent CSF leak or recurrent meningitis

May be associated with other craniofacial deformities, including: cleft lip, bifid nose, optic-nerve dysplasia, coloboma and microphthalmia, hypothalamic-pituitary dysfunction.

32
Q

Define Dandy Walker Malformation

A

enlarged posterior fossa with partial (hypoplasia) or complete agenesis of the cerebellar vermis and cystic dilatation of the fourth ventricle which is distorted and encased in a neuroglial vascular membrane. Hydrocephalus is also present

33
Q

How do you differentiate between Dandy Walker malformation/variant and Blakes Pouch Cyst

A

in BPC there is no vermian agenesis or hypoplasia

34
Q

What is Joubert’s syndrome?

A

Absence or underdevelopment of cerebellar vermis

35
Q

What is PHACES syndrome?

A

acronym for a group of findings including Posterior fossa malformations, cervicofacial Hemangioma, Arterial anomalies of the head and neck, Coarctation of the aorta and cardiac defects, Eye anomalies and Sternal cleft. Ratio girls:boys = 9:1. Thought to begin during gestation weeks 8–10

36
Q

What is the treatment of Dandy Walker?

A

Shunting the posterior fossa cyst and management of the hydrocephalus. If no hydrocephalus can be managed conservatively

37
Q

What causes aqueductal stenosis?

A

congenital - associated with chiari or NF

Acquired
Inflammation (following haemorrhage or infection)
Tumours/cysts

38
Q

Treatment options for aqueductal stenosis?

A

VP shunt

a Torkildsen shunt (shunting a lateral ventricle to the cisterna magna) may work in adult cases

Endoscopic third ventriculostomy

39
Q

What is Aicardi syndrome?

A

agenesis of CC, seizures, retardation, patches of retinal pigmentation. likely X-linked

40
Q

What is the incidence of intracranial lipomas?

A

8 in 10 000 on autopsy series

41
Q

What conditions are associated with intracranial lipomas?

A

other midline abnormalities - agenesis of CC, spina bifida, encephalocoele, Myelomeningocoele.

42
Q

How do hypothalamic hamartomas present?

A

gelastic seizures - present in 92%
epileptic encephalopathy

precocious puberty
developmental delay - worse if epileptic encephalopthy prolonged
behavioural disturbance

43
Q

What are the subtypes of hypothalamic hamartoma?

A

pedunculated or parahypothalamic: narrower base attached to the floor of the hypothalamus (not arising within hypothalamus). No distortion of 3rd ventricle. Generally associated with precocious puberty more than seizures

intrathalamic or sessile: within hypothalamus (distorting the 3rd ventricle) or broad attachment to hypothalamus. More often associated with seizures. 66% have developmental delay, 50% have precocious puberty

44
Q

What is the first line treatment of hypothalamic hamartomas?

A

Symptomatic. Precocious puberty treated with GnRH analogues and antiseizure medication for gelastic seizures.

Surgical/stereotactic intervention indicated for those refractory to medical treatment

Greenberg (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions