Fetal Head Abnormalites numero dos Flashcards
What is Holoprosencephaly?
failure of division of the prosencephalon (fore brain) resulting in varying degree of prosencephalon midline defects
What is the clinical presentation of holoprosencephaly?
proboscis cyclopia cleft lip/palate occular hypotelorism colitary median maxillary central incisor
What chromosomal abnormalities are associated with holoprosencephaly (aneuploidic)
Tri13 (most common)
Tri18
What is associated with holoprosencephaly (non-aneuploidic)
congenital renal anomalies congenital cardiac anomalies diabetic embryopathy facial anomalies shprintzen syndrome
What are the 3 subtypes of holoprosencephaly
alobar
semilobar
lobar
What is alobar holoprosencephaly
thalami are fused
single posterior ventricle
a/w: facial abnormalities– cyclopia, ethmocephaly, cebocephaly and median cleft lip
What is semi lobar holoprosencephaly
central lobes are present: most commonly fused anteriorly and at the thalami
olfactory tracts/bulbs are not present
agenesis/hypoplasia of CC
What is lobar holoprosencephaly
least affected
more subtle midline abnormalities: fusion of cingulate gyrus and thalami
olfactory tracts/CC can be absent or hypoplastic
Is holoprosencephaly compatible with extra uterine life?
not usually
depends on type
What is the most common type of holoprosencephaly
Alobar
There’s a lotta shit on holoprosencephaly so
review the slides
What is hydranencephaly
gross ventriculomegaly due to complete or near complete absence of cerebral tissue
What does hydranencephaly appear as?
absence of the cerebral hemispheres with an incomplete or absence falx and a sac-like structure cerebral fluid surrounding the brainstem and basal ganglia
What is the key sonographic feature of hydranencephaly?
large cranial fluid collection lacking a mantle or rim of cerebral brain tissue
Is hydranencephaly compatible with life?
no