[Leigh's encephalopathy (subacute necrotizing encephalopathy). Documentation of its evolution through neuroimaging].

A 30 months-old boy developed bilateral nistagmus, tremor, gait disturbance, hypotonia and disartria. The diagnose of Leigh encephalopathy was suggested on the basis of clinical, neuroimaging and laboratory findings. Computed tomography and magnetic resonance imaging (MRI) at an early stage revealed bilateral and symmetric lesions in the putamen, appearing as hyperintense signal on T2-weighted images. Twelve months later a relatively large hypertense area in the posterior brainstem was observed. At this stage, the patient exhibited marked deterioration, dystonic manifestations, rigidity and respiratory disturbances. He died 6 months later for respiratory arrest during bronconeumonic infection. We believe MRI is a valuable means to allow assessment of the evolution of the disease.