Subacute necrotizing encephalomyelopathy (Leigh disease): CT study.

Leigh disease, or subacute necrotizing encephalomyelopathy (SNE), is a familial, degenerative disorder characterized by lesions of the gray and white matter in the brain and spinal cord. Low attenuation in the putamina on computed tomography (CT) scans is considered to be characteristic of the disease. The authors used CT to study five patients, in three of whom the disease was confirmed histologically. In one of the patients with documented SNE, there was extensive gray matter lucency with normal basal ganglia. CT scans obtained in a second patient showed diffuse, diseased white matter with focal cortical extension and bilateral caudate involvement. In the other three cases, CT scans revealed the usual changes that occur in the basal ganglia. The appearance of SNE on CT scans thus reflects the variable and widespread distribution of the disease. The absence of radiologically detectable abnormalities in the basal ganglia should not deter one from the diagnosis of Leigh disease given in the appropriate clinical context.