RADIOLOGY MCQ---FRCR

Q. Hyperdense basal ganglia and thalami is seen In

a. Mucopolysaccharidoses

b. Zellweger syndrome

c. Alexander disease

d. MELAS

e.Krabbe disease

ANS.---e

Krabbe disease, or globoid cell leukodystrophy (GLD)----

An autosomal recessive inherited disorder that commonly presents within the first 6 months of life., Deficiency of the lysosomal enzyme galactocerebroside β-galactosidase (encoded by chromosome 14)  results in the accumulation of galactocerebroside in macrophages

The brain is small and weighs only 600 to 800 g The white matter is rubbery to firm, but the cortex is relatively unaffected .The pathologic hallmark of Krabbe disease is a massive accumulation of large multinucleated cells containing periodic acid-Schiff–positive material (globoid cells) 

. In contrast to other demyelinating diseases, lipid-laden macrophages are uncommon. Demyelination and dysmyelination are seen.

The most characteristic MR finding in both the infantile and late-onset forms of GLD is high signal intensity on the T2-weighted images found along the lengths of the corticospinal tracts.

The cerebellar white matter and deep gray nuclei are not involved in the late-onset form

The CT findings of hyperdense thalami, caudate nuclei, and corona radiata are characteristic but not specific for the disease and have been shown to correspond to fine calcifications at autopsy .

 Late-onset cases of GLD with primary involvement of the parietal periventricular white matter, splenium of the corpus callosum, and corticospinal tracts may appear similar on imaging to adrenoleukodystrophy. However, auditory pathway involvement is characteristic of adrenoleukodystrophy and is not seen in GLD.