chapter 24 fetal head and brain

the third ventricle is located

between the two lobes of the thalamus

with what structure does the posterior fossa cyst associated with DWM communicate?

fourth ventricle

the sonographic finding of a fluid-filled cranium with absence of cerebral tissue is consistent with:

hydranencephaly

following an intracranial hemorrhage, a cyst is noted within the cerebrum that communicates with the lateral ventricle. This is referred to as:

porencephaly

all of the following are sonographic findings of arnold-chiari 2 malformation except: -enlarged massa intermedia -hydrocephalus -obliteration of the cisterna magna -strawberry sign

strawberry sign

the interthalamic adhesion (massa intermedia) passes through the:

third ventricle

the most common cause of hydrocephalus in utero is

aqueductal stenosis

the cisterna magna should not exceed _____ in the transcerebellar plane

10mm

the anechoic midline brain structure located between the frontal horns of the lateral ventricles is the:

CSP

enlargement of the frontal horns and narrowing of the occipital horns is termed:

colpocephaly

the double fold of dura mater that divides the cerebral hemispheres is the:

falx cerebri

a cloverleaf-shaped skull is related to

thanatophoric dysplasia

the fourth ventricle is located:

anterior to the cerebellar vermis

what cerebral abnormality are atypical facial features most commonly associated with?

holoprosencephaly

the development of fluid-filled cleft within the cerebrum is consistent with:

schizencephaly

what chromosomal aberration is most often associated with holoprosencephaly?

trisomy 13

a strawberry-shaped skull is commonly associated with

trisomy 18

the choroid plexus cyst could be associated with an increased risk of

trisomy 18

dangling choroid plexus sign is associated with:

ventriculomegaly

which of the following will also typically be absent with agenesis of the corpus callosum? -cerebellar vermis -CSP -corpus callosum -falx cerebri

CSP

what cerebral malformation is as a result of agenesis of hypoplasia of the cerebellar vermis?

DWM

absence of the skull is

acrania

the most severe form of holoprosencephaly is

alobar

which of the following is a genetic disorder that includes craniosynostosis, midline facial hypoplasia, and syndactyly? -lobar holoprosencephaly -beckwith-wiedemann syndrome -arnold-chiari 2 malformation -apert syndrome

apert syndrome

the third ventricle communicates with the fourth ventricle at the:

aqueduct of sylvius

a lemon-shaped skull is related to:

arnold-chiari 2 malformation

the structure located between the two lobes of the cerebellum is the:

cerebellar vermis

the band of tissue that allows communication between the right and left cerebral hemispheres is the:

corpus callosum

all of the following are sonographic features of alobar holoprosencephaly except: -cyclopia -monoventricle -dorsal cyst -fused thalamus

dorsal cyst

which of the following should not be included in the correct level for an HC measurement? -falx cerebri -fourth ventricle -thalamus -CSP

fourth ventricle

which of the following would be the most likely fetal cranial findings with TORCH infections?

intracranial calcifications

a cisterna magna that measures 15 mm and a normal appearing cerebellum is most likely

mega cisterna magna

the "sunburst" of the cerebral sulci is a sonographic finding of:

agenesis of the corpus callosum

the condition in which the frontal horns are small and the occipital horns are enlarged is referred to as:

colpocephaly

the most accurate measurement for estimating gestational age is

HC

which of the following is located on both sides of the midline? -interhemispheric fissures -third and fourth ventricles -lateral ventricles -third ventricle and cerebral aquedact

lateral ventricles

the lack of sulci within the fetal cerebrum is a reliable indicator of:

lissencephaly

which of the following would not be normally located within the midline of the fetal brain? -CSP -lobes of the thalamus -third ventricle -falx cerebri

lobes of the thalamus

a normal shaped skull is termed

mesocephaly

what fetal suture is located within the frontal bone along the midline of the forehead?

metopic suture