Theme 1 Questions - NTDs

Neural Tube Defects

Give the incidence of the following NTDs:
Anencephaly
Spina Bifida
Craniorachisis
Enencephalocle

Anencephaly - 40 percent
Spina Bifida - 40 percent
Craniorachosis - 10 percent
Enencephalocele - 10 percent

What is the golden standard for diagnosis of S.B prebirth?

Ultrasound scan at 20wks

What is tethered cord syndrome?

Spinal cord attaches to spine, resulting in a stretch that can lead to nerve and muscle damage.

what device is used in keyhole surgery of SB prebirth

fetoscope

Why does hydrocephalus develop after open SB is closed?

Normal routes of CSF drainage have not opened.

What percentage of NTDs are prevented by folic acid?

Up to 70 percent. Maybe more with inositol

4 big differences between brainstem-spinal cord development and cerebral development?

Cerebral development is not controlled by notochord signalling. See instead, CSF signalling.

Hox genes for brainstem. Emx and Otx for cerebrum.

Timing - Spinal cord at 3-5wks, cerebrum much later, mainly at about 15 -20 wks

CSF flow changes a lot in the cerebrum to form the ventricles. Radial glial fibres act as a scaffold for cells to migrate. Cortical heterotopias can arise from improper signalling.
CSF not getting to subarachnoid space means normal proliferation but no migration.

Which enzyme catalyses dihydrofolate to THF?

DHF-reductase

Which foods have the most folate?

Leafy greens.