L 1 - IMAGING AD

Question 0

MMSE scores associated with MCI, mild, moderate, and severe AD:

Answer 0

MCI: 24-30

mild: 20-23
moderate: 10-19
severe: 0-9

Question 1

MMSE

Answer 1

The mini–mental state examination (MMSE) or Folstein test is a brief 30-point questionnaire test that is used to screen for cognitive impairment. It is commonly used in medicine to screen for dementia. It is also used to estimate the severity of cognitive impairment and to follow the course of cognitive changes in an individual over time, thus making it an effective way to document an individual’s response to treatment.

Question 2

Indications of AD in an MRI

Answer 2

T1 weighed MRI contrast shows brain atrophy

Question 3

Why is fMRI BOLD?

Answer 3

Blood Oxygen Level Dependent

Question 4

fMRI indications of AD

Answer 4

Decreased activation in areas (which?) during tasks

Question 5

What is DTI and how may it distinguish AD patients?

Answer 5

• Diffusion Weighted/Tensor Imaging
• Neurodegeneration appears to begin in the neural periphery (axons/dendrites), which makes white matter a good early target

Question 6

ASL MRI

Answer 6

• Arterial Spin Labeling (labeling arterial blood as an endogenous tracer)
• quantitative assessment of blood flow
• shows decreased blood flow to certain areas of the brain in AD patients

Question 7

MRS in AD

Answer 7

• Magnetic resonance spectroscopy. Uses the unique chemical composition of cell metabolites
• Decreased glutamate activity in AD (Rupsingh, 2011)
• NAA (N-acetylaspartate) - a measure of neuronal integrity in MRS studies (reduced in AD patients)
• Also, inconsistent changes in choline and creatine in AD

Question 8

Blood-brain barrier in AD

Answer 8

Blood brain barrier becomes more permeable (?)

Question 9

PET compounds in AD

Answer 9

• Pittsburgh compound B (11C) - beta-amyloid plaques (C half-life - 20 min)
• Florbetapir (18F) - beta-amyloid - half-life 110 min
  Pyridinated PBB (11C) - binds to tau fibrils

Question 10

PET scan power to discriminate between AD and normal aging plaques…

Answer 10

15-25% of older people with no cognitive symptoms show the same amount of amyloid build-up (Mormino et al., 2009)