A number of changes can be seen in MRI of the brain of a patient with Alexander’s disease. The presence of MRI findings may be an indication to perform molecular testing.


Criteria for an MRI-based diagnosis of Alexander disease – 4 or more of the following:

(1) extensive cerebral white matter abnormalities, which may be maximal in the frontal lobes

(2) periventricular rim of (a) decreased signal intensity on T2-weighted images and (b) increased signal intensity on T1-weighted images

(3) abnormalities in the thalami and basal ganglia (atrophy, swelling, altered signal intensity on T2-weighted images)

(4) brain stem abnormalities

(5) contrast enhancement of one or more of the following: ventricular lining, periventricular rim, frontal white matter, optic chiasm, fornix, basal ganglia, thalami, dentate nucleus, brain stem


Additional MRI changes may include:

(1) involvement of the posterior fossa structures

(2) multifocal tumor-like brain stems lesions

(3) garland-like feature along the ventricular wall

(4) characteristic pattern of contrast enhancement

(5) atrophy or signal abnormalities of the medulla or spinal cord


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