Neural tube defects Flashcards
hydranencephaly
post-neurolation defect.
Only small bands of cerebrum remains.
Thought to be due to bilateral ICA infarcts.
Cavity filled with CSF
Differential diagnostic to hydranencephaly?
extreme hcph.
How to differ hcph and hydranencephaly?
By EEG. Hydranencephaly doesnt show any activity at all. Extreme hcph show abnormal activity and background activity.
Another way, for the typical hydranencephaly is angiography that will not show any anterior circulation.
Does the head enlarge in hydranencephaly like in hcph?
Yes, it might, although usually not in the same way.
How does hydranencephaly children act?
Normal initially.
But at 6mo still primitive reflexes.
rarely progress beyond social smiling and seizures are common.
What is Holopros encephaly?
Failure of the telencephalic vesicle to cleave into 2 cerebral hemispheres.
From severe alobar to semilobar and lobar.
80% of Holoprosencephaly have a genetic defect. Which?
Trisomy 13.
How long does Holoprosencephaly patients survive?
Usually not beyond infancy.
What is microcephaly?
head circumference less than 2SD from standard.
Why is it important to differentiate microcephaly from craniocynostosis?
Treatment might improve cerebral development in craniosynostosis pt.
Risk factors for microcephaly?
- infections during pregnancy: Rubella, toxoplasmosis, cytomegalovirus, zika virus
- Severe malnutrition
*maternal exposure to cocain or alkcohol
*interruption of blood supply during pregnancy
prenatal detection of neural tube defects are done in several ways. Name 3.
- Serum alpha-fetoprotein
- Ultrasound
- Amniocentesis
How high sensitivity does sAFP have for spina bifida?
91%
How high sensitivity does sAFP have for anencephaly?
100%
What is the risk of AFP?
It is correlated to gestational age. If it is wrong, AFP might be under or over-estimated.
