Canavan Disease:
Canavan disease is a severe progressive leukodystrophy characterized by swelling
and spongy degeneration of the white matter of the brain. It is an autosomal
recessive disease found more frequently among Ashkenazi Jews. This MRI is of
a one and half year old female child from Myagdi, Gandaki Zone, who presented
with the history of difficulty in walking for two months duration. The clinical
features are thse of severe mental retardation with inability to gain developmental
milestones. Hypotonia, head lag and macrocephaly are characteristic of Canavan
disease and become apparent after 5-6 months of age. Massive excretion in the
urine of N-acetylaspartic acid is the biochemical marker for Canavan disease,
which is caused by deficiency of the enzyme aspartoacylase. Computed Tomography
(CT) scan of the head or Magnetic Resonance Imaging (MRI) of the brain reveal
diffuse white matter degeneration. There is no treatment.

