10.2 - Clinical applications of Neuroimaging

Question 1

In a 7-year follow-up study what happens to cerebellar volume in patients with coeliac disease? How was neuroimaging techniques used in this study?

Answer 1

-rate of cerebellar atrophy is greater in coeliacs which are still positive for gluten antibodies compared to coeliacs negatives for antibodies
-volume of cerebellum calculated using VBM and FSL

Question 2

What can fMRI tell you about speaking first/native and second languages?

Answer 2

-due to higher activation in Brocas and Wernickes area when speaking second language compared to speaking native
-this is because more activity/control is required for second as speaker has to also supress native language

Question 3

What evidence is there that when speaking a second language, you have to supress the native language?

Answer 3

strokes can affect this suppression activity in the brain -> left with only native after stroke

Question 3

Why is DWI/ADC imaging better at diagnosing a cerebral abscess than standard structural imaging (T1)?

Answer 3

DWI/ADC can distinguish between the potential options: abscess, tumour or haematoma? whereas T1 cant
DWI shows reduced ADC value due pus centre of abscess (restricted diffusion) whereas tumours show increase diffusion ADC

Question 4

What is the practicality issue of DTI images (compared to DWI)?

Answer 4

DWI only uses 3 directions whereas DTI uses many more (like 30) -> DTI takes at least 6minutes to acquire the most basic scan

Question 5

What is the issue with using diffusion tractography for tumour imaging in clinical practice?
ditto for oedemas

Answer 5

Fibre tracking controversial: as soon as one gets near to the tumour the data becomes unreliable
tractography tracts stop when they get to oedema = no data

Question 6

What is benefit of NODDI over traditional DTI?

Answer 6

NODDI provides more reliable measurements in cortical GM because the CSF contribution is modelled separately

Question 7

What is a potential clinical application of Neurite Density Index NODDI for focal cortical dysplasia?

Answer 7

-lesion is more apparent than other imaging types because NODDI provides more reliable measurement on GM
-focal cortical dysplasia is the most common causes of drug-resistant epilepsy in youthes

Question 8

How is DTI used with coeliac disease and cognitive?

Answer 8

DTI used to show there was a correlation between changes in WM integrity and cognition(more depressive symptoms)