Subcortical spongy changes of the white matter. The cortex above is spared. The dark stained neurons are not affected.Canavan disease, one of the most common cerebral degenerative diseases of infancy, is a gene-linked, neurological birth disorder in which the white matter of the brain degenerates into spongy tissue riddled with microscopic fluid-filled spaces.
It occurs due to a deficiency of the enzyme called Aspartoacylase, since the gene which usually tells the body to produce this enzyme is faulty. Babies are born apparently unaffected. At 2 to 4 months of age, he/she develops poor head control and seizures.