Neuroimaging

Question 1

What is a technical challenge with diffusion tensor imaging?

Answer 1

The presence of crossing fibers and therefore susceptible to false positives and negatives

Question 2

Increased diffusivity of fiber tracts is associated with what?

Answer 2

Poorer verbal but not nonverbal performance

Question 3

Is gadolinium necessary in epilepsy MRI protocols?

Answer 3

No

Question 4

Can low grade tumors be detected using epilepsy protocols?

Answer 4

Yes, on intermediate T2/FLAIR

Question 5

What sequences on MRI are needed for epilepsy?

Answer 5

FLAIR, T-2, T-1, hemosiderin/calcification. Slice thickness should not exceed 3 mm

Question 6

How should the T1 sequence be acquired?

Answer 6

A three dimensional technique at a 1 mm isotopic voxel size

Question 7

How should the hippocampus be viewed?

Answer 7

At least 2 slice orientations

Question 8

Diffusion tensor imaging abnormalities predict focal seizures?

Answer 8

No, although diffusion changes maybe more prominent on the side of seizure onset but there are also remote and contralateral diffusion abnormalities.

Question 9

In ictal SPECT studies is there a difference between right temporal lobe seizures and left temporal lobe seizure onst?

Answer 9

Yes, there is a lesser degree of hyperperfusion in the midbrain of patients with right temporal lobe epilepsy.

Question 10

Why are Cavernoma with hemorrhage easily visualized on routine MRI?

Answer 10

Due to susceptibility.

Question 11

What measurement can be derived from diffusion tensor imaging?

Answer 11

Fractional anisotropic

Question 12

How is gray matter density derived?

Answer 12

Voxel-base morphometry

Question 13

Are there anatomical abnormalities other than hippocampal sclerosis in TLE?

Answer 13

Yes, quantatitive structural neoroimaging has shown anatomical abnormalities in cortical and subcritical regions. Both ipsilateral and contralateral.

Question 14

Lissencephaly is caused by a neuronal migration during what time period in gestation?

Answer 14

12 any 24 weeks after conception

Question 15

What is the default network seen on fMRI?

Answer 15

A nateork that shows increased activity during rest compared to during cognitive tasks

Question 16

What syndrome sows MRI evidence of progressive atrophy in widespread neocortex all regions?

Answer 16

Drug-resistant temporal lobe epilepsy

Question 17

What MRI findings were found in temporal lobe epilepsy?

Answer 17

Cortical thinning in the frontocentral, temporal, and cingulate regions

Question 18

What epileptogenic lesion is there diagnostic evidence that post-processing is superior to visual analysis

Answer 18

Class II evidence that imagine processing accurately identified focal cortical dysphasia type II with extratemporal epilepsy

Question 19

What are the characteristics of bottom of the sulcus dysphasia?

Answer 19

Infant or early onset of diurnal focal seizures, chronic nocturnal seizures, high frequency of seizure in clusters, often with prolonged remissions

Question 20

Is early development normal in bottom of the sulcus dysphasia?

Answer 20

Yes unless seizures begin during infancy. There can be executive dysfunction, and/or language defects

Question 21

What is the sign of retinal toxicity on ERG?

Answer 21

Decreased amplitude

Question 22

What is the most frequent location of poly micro gyrus?

Answer 22

Perisylvian- bilateral and symmetric

Question 23

Pathological findings of medial temporal lobe sclerosis?

Answer 23

Gloss’s and loss of neurons in CA1 and CA3 regions as well as Hulu’s and dent are.