CNS malformations book Flashcards
Exposure to a teratogen may cause CNS malformations if it occurs at 3 to 8 weeks of gestation and have minimal or no effects if it occurs later
Exposure to teratogens during the period of organogenesis (3 to 8 weeks) may cause severe malformations. Exposure at a later time may have minimal or no effects.
Congenital CMV infection at 9-12 weeks of gestation can cause:
Porencephaly
Polymicrogyria
Schizencephaly
Congenital CMV infection starting at 37 weeks gestation can cause:
CMV encephalitis
Hydranencephaly
Hydranencephaly is not a neural tube defect. In most instances, it is an ischemic disruption.
neural tube defects?
Exencephaly
Anencephaly
Encephalocele
To be effective in preventing neural tube defects, women of child-bearing age must take 0.8 mg folic acid daily:
4 weeks before to 8 weeks after conception Supplementation with 0.8 mg of folic acid, minerals, and trace elements daily, starting at least one month before conception and until the date of the second missed menstrual period or later prevents most neural tube defects.
*Mutation of which is associated with NTDs?
MTHFR
Holoprosencephaly (HPE) may be associated with ____?
Fusion of the thalami
Fusion of the frontal lobes
Absence of the olfactory nerves
Abnormal cortical cytoarchitecture
NOT Hydrocephalus or Cerebellar hypoplasia
In alobar HPE, there is a single ventricle. In lobar HPE, the ventricles are usually normal in size.
Alobar HPE is incompatible with survival
TRUE
A newborn baby with a single central incisor may have:
HPE
Which mutations are associated with NTDs?
MTHFR 677 and 1928
Both MTHFR mutations are associated with NTDs. Compound heterozygotes for MTHFR 677 C to T and MTHFR 1298 A to T produce an enzyme with decreased activity, similar to MTHFR 677 C to T homozygotes.
