NEURODEGENERATIVE DISEASES

 

AMYLOID IMAGING --MCQ

 

Q1 .Radiopharmaceuticals used for BETA amyloid imaging  are all  except 

a, 18F-florbetapir

b.18Fflorbetaben

c. 18F-flutemetamol

d.123I-Ioflupane

1.Ans--d

Q2.All are true regarding beta amyloid imaging except 

a.uptake by white matter normal 

b.inceased cortical uptake abnormal

c.cerebellum used as internal control 

d.crebellum shows most heavy amyloid depostion 

2Ans---d

A relatively new group of contrast agents exists that allows visualization of abnormal amyloid deposition . Although the original agent was carbon 11–Pittsburgh compound B, the current major radiopharmaceuticals in this group are all tagged with 18F and include 18F-florbetapir, 18Fflorbetaben, and 18F-flutemetamol. T

At neurologic imaging, normal white matter takes up these agents. The mechanism is not well understood, but research suggests it may bind to myelin-binding proteins and could be used in the workup of demyelinating diseases

At β-amyloid imaging, areas of increased cortical uptake are considered abnormal and correspond to cortical deposition of β-amyloid plaques. An internal control is used to establish a normal uptake pattern, with the cerebellum typically used to compare gray-white differentiation, as the cerebellum rarely has abnormal amyloid accumulation.

RADIOGRAPHICS 

WORK-UP of patients with suspected dementia

 

WORK-UP of patients with suspected dementia 

MCQ MRI BRAIN

 

Above MRI image ( coronal section) of brain shows 

a.extraaxial sol

b.edema 

c.left ward midline shift 

d.tansfalcine herniation 

e.all

ANS---e ( all )

CINGULATE ISLAND SIGN

Q.CINGULATE ISLAND SIGN on FDG -PET SCAN of brain is noted in 

a.Alzheimer disease

b.DLB 

c.both \

d.none 

ANS---b ( DLB)

----The typical pattern of hypometabolic activity in Alzheimer disease on 18F-FDG PET images involves the parietotemporal region, precuneus, and posterior cingulate gyrus, with sparing of the sensorimotor strips and occipital region, which usually corresponds to the atrophic changes depicted on structural images. 

----In patients with DLB, 18F-FDG PET images show asymmetric decreased activity in the frontotemporal lobes similar to that depicted in Alzheimer disease. However, there is preserved metabolism of the posterior cingulate cortex, resulting in the so-called cingulate island sign. Alzheimer disease almost invariably involves the posterior cingulate gyrus, and this is a useful differentiating factor. There is hypometabolism of the occipital lobes, which is helpful to differentiate DLB from typical Alzheimer disease.

MRI PROTOCOL FOR MS AND ITS FOLLOW-UP STRATEGY

 

FROM RADIOGRAPHICS