Advances and applications in fetal magnetic resonance imaging 2015 TOG

Question 1

Difference of T1 and T2 weighted

Answer 1

T1 High water content seen as low signal intensity
T2 High water contract seen as low signal intestity

Question 2

Is T1 or T2 preferred in fetus

Answer 2

T2 produced better image
But T1 can be useful for looking for haemorrhage, fat or myelin in the mature brain

Now fast T2 imagines can image head in 30 seconds

Question 3

Maximum rise in termpature in normal mode and controlled mode

Answer 3

Normal 0.5
Controlled 1.0

Question 4

Most common CNS anomaly detected on USS

Answer 4

Ventriculomegaly >10mm

Question 5

What is the most common CNS abnormality to be missed by USS?

Answer 5

Agenesis of corpus calllsum

For example, 17% fetes who had ventoculomegaly on USS had further abnormality detect on MRI of which genesis of corpus callous is more common

Question 6

What us holoprosencephaly?

Answer 6

Single large ventricle and fusion of thalami, absent corpus callosum, fax cerebra and cave septum pelluidi.

Variable midfacial maldevelopment

Question 7

What is myelomeningocele?

Answer 7

Absence of the posterior aspect of the vertebral bodies & extension of the subarachnoid space through the defect.

Associated with Arnold-Chiari malformation. Downward displacement of cerebellar tonsils through the foramen magnum, causing ventricular dilation

Question 8

What is encephalocele?

Answer 8

Bony defect in skill enabling herniation of meninges +/- brain tissue.

Additional malformations in 38%