brain - part 3

Question 1

intracranial pathologies? (9)

Answer 1

Intracranial Hemorrhage  - ICH
Hydrocephalus
Cerebellar Hemorrhage
Periventricular Leukomalacia – PVL
Agenesis of Corpus Callosum
Dandy-Walker complex
Chiari Malformation
Holoprosencephaly
Intracranial Infections

Question 2

what is Hydrocephalus?

Answer 2

• progressive dialation of ventricular system

Question 3

3 mechanisms of Hydrocephalus?

Answer 3

1. obstruction to CSF outflow
2. decreased CSF absorption
3. CSF overproduction

Question 4

what can cause Hydrocephalus?

Answer 4

hemorrhage grade 3 and 4

Question 5

Hydrocephalus clinical signs?

Answer 5

• increasing head size
• bulging of the anterior frontanelle
• separation of cranial sutures

Question 6

why are serial u/s required to monitor the progression of Hydrocephalus?

Answer 6

because bradycardia, apnea, and increased ICP appear days or weeks later

Question 7

Answer 7

post hemorrhagic hydrocephalus

• shows grade III hemorrhage
• hydrocephalus with clot in lateral and 3rd ventricle
• ependymal lining of ventricles in increased in echogenicity consistent with ependymitis

Question 8

what is ependymitis caused by?

Answer 8

• blood products/ chemical ventriculitis

Question 9

Infants with progressive hydrocephalus and increased ICP may require ?

Answer 9

placement of a shunt

Question 10

Hydrocephalus u/s scan?

Answer 10

• Doppler used to identify infants with increased ICP
• Compression of anterior fontanelle with transducer while obtaining a spectral Doppler from pericallosal artery (anterior cerebral a.)
• Compress gently for 3 – 5 sec
• Do not compress if you see reversal of flow without compression
• Stop compression if heart rate goes down.

Question 11

Cerebellar hemorrhage clinically?

Answer 11

• may be silent and found on routine cranial U/S

Question 12

Cerebellar hemorrhage approach?

Answer 12

• mastoid frontanelle approach is used
• cerebellum is in far field in anterior frontanelle scan
• highly echogenic tentorium is avoided

Question 13

posterior fossa

Answer 13

Normal posterior fossa structures obtained via the mastoid fontanelle

Coronal sonogram shows a normal

• 4th ventricle (4)
• cerebellar hemispheres (*)
• midline vermis (V)
• cisterna magna (CM).

Question 14

Answer 14

Coronal image shows large echogenic hemorrhage in the right cerebellar hemisphere (arrows).

Question 15

Answer 15

Coronal scan shows clot (c) in dilated fourth ventricle (4).

Question 16

Periventricular Leukomalacia (PVL)?

Answer 16

• Hypoxic-ischemic brain injury
• Hypoxia – lack of O2
• Ischemia – lack of adequate blood flow
• Leukomalacia – softening of white matter

Question 17

common sites for Periventricular Leukomalacia (PVL)?

Answer 17

• White matter adjacent to peritrigonal area of lateral ventricles
• Frontal cerebral white matter anterolateral to frontal horns

Question 18

Periventricular Leukomalacia (PVL) on u/s?

Answer 18

SONO – not very reliable
Increased echogenicity in affected area
Bilateral and symmetric
Echogenicity should not be > choroid plexus
Difficult to differentiate from periventricular blush
Later changes to PVL
Formation of cysts as a result of necrosis and cavitation

Question 19

Periventricular Leukomalacia (PVL) long term affects?

Answer 19

cerebral palsy
developmental abnormalities
intellectual and visual impairment

Question 20

Answer 20

Periventricular Leukomalacia in Premature Infant

Question 21

Answer 21

evolving PVL

Question 22

Answer 22

agenesis of corpus callosum

Question 23

Agenesis of the Corpus Callosum?

Answer 23

• Complete or partial absence of the hypoechoic band superior to 3rd ventricle
• Frontal horns widely separated and angled laterally
• Occipital horns have parallel orientation and a teardrop shape
• Enlargement of posterior (occ.) horns (colpocephaly)
• Radial arrangement of sulci and gyri above 3rd ventricle – sunburst sign
• Absent CSP*, high and enlarged 3rd ventricle

Question 24

sunburst sign is associated with?

Answer 24

agenesis of corpus callosum

Question 25

Dandy-Walker Malformation?

Answer 25

A spectrum of anomalies of posterior fossa: - Cystic dilatation of 4th ventricle - Superior elevation of the tentorium - Absence of vermis - Small cerebellar hemispheres - Hydrocephalus

Question 26

Dandy-Walker Malformation is associated with?

Answer 26

Associated with many other cerebral (agenesis of CC, holoprosencephaly) and non-cerebral anomalies (cystic renal dx, chromosomal and cardiac)

Question 27

Answer 27

dandy walker malformation

Question 28

Chiari Malformation most common type?

Answer 28

chiari II

Question 29

Chiari Malformation is almost always associated with?

Answer 29

myelomeningocele

Question 30

Chiari Malformation on sono?

Answer 30

Hydrocephalus with prominent massa intermidia Inferior pointing of frontal horns – “bat wing” Downward displacement of cerebellum and 4th v. into spinal canal Non-visualized cisterna magna Small posterior fossa Low and displastic tentorium Colpocephaly (large occ. horns) Complete or partial CC agenesis

Question 31

Answer 31

chiari II malformation

Question 32

Vein of Galen Malformation?

Answer 32

Most common intracranial vascular anomaly in neonate Midline cerebral AV malformation that causes dilatation of v. of Galen Anterior and posterior cerebral aa. feed the malformation Decreased blood supply to brain – atrophy and calcifications of brain

Question 33

what is the most common intracranial vascular anomaly in neonate?

Answer 33

vein of galen malformation

Question 34

Answer 34

vein of galen malformation

Question 35

Holoprosencephaly?

Answer 35

Spectrum of congenital malformations that result from a disorder of diverticulation in which the primitive forebrain (prosencephalon) fails to divide into two separate cerebral hemispheres

Question 36

3 kinds of holoprosencephaly?

Answer 36

alobar- most severe semilobar lobar- least severe

Question 37

holoprosencephaly result?

Answer 37

``` Infants with alobar type are stillborn or die shortly after birth Severe facial anomalies Close set eyes – hypotelorism Cyclopia Proboscis – nose on forehead Cleft lip/palate ```

Question 38

Alobar holoprosencephaly?

Answer 38

There is a thin pancake like primitive cerebrum covering a horseshoe shaped midline monoventricle ``` Missing: Corpus callosum Third ventricle Interhemispheric fissures Thalami are fused ```

Question 39

semilobar holoprosencephaly?

Answer 39

Incomplete forebrain division with partial separation of the cerebral hemispheres posteriorly Single ventricle with occipital and temporal horns formed Falx may be present 3rd v. is small or absent

Question 40

Answer 40

alobar holoprosencephaly

Question 41

Most common neonatal congenital infections are referred to as?

Answer 41

TORCH complex

Question 42

what is TORCH?

Answer 42

``` T  Toxoplasmosis O  Others R  Rubella C  Cytomegalovirus CMV H  Herpes Simplex ```

Question 43

INTRACRANIAL INFECTION?

Answer 43

TORCH

Question 44

Most common intracranial infection?

Answer 44

CMV - Toxoplasmosis is 2nd

Question 45

intracranial infection if trasmited via?

Answer 45

placenta - herpes transmits at birth from contact with vaginal lesions

Question 46

how are CNS infections diagnosed?

Answer 46

clinically

Question 47

u/s role in intracranial infection?

Answer 47

used to determine complications - Parenchymal calcifications - Lenticulostriate vasculopathy

Question 48

Answer 48

cytomegalovirus infection

Question 49

Answer 49

Lenticulostriate Vasculopathy