Specific Imaging Findings

MR imaging in Leigh disease (LD) usually reveals bilateral symmetrical T2 hyperintense lesions of the deep gray matter and brainstem. Putamen is typically involved, followed by the caudate nuclei. The globi pallidi and thalami area less frequently affected. Brainstem lesions including the subthalamic nuclei, substantia nigra, red nuclei, colliculi, periaqueductal gray matter, and medulla oblongata are commonly present. Cerebellar dentate nuclei are also a frequent location of T2 hyperintensity. Spinal cord, hemispheric white matter and cerebral cortex involvement may occur. Acutely affected areas may show reduced diffusivity on ADC maps. MRS usually reveals elevated lactate, most prominent within the lesions. Normal MRS, however, does not exclude LD.

Pertinent Clinical Information

Leigh disease is a frequently lethal disorder that usually presents during infancy, and rarely during childhood and later in life. Developmental delay, seizures, and altered consciousness are the most common presenting symptoms. Generalized weakness, hypotonia, nystagmus, ataxia, dystonia, lactic acidosis and respiratory failure with apneas are also frequently present. Visceral manifestations comprise failure to thrive, cardiomyopathy, liver function impairment and proximal renal tubulopathy.