Pallido-nigro-luysial atrophy associated with degeneration of the centrum medianum. A clinicopathologic and electron microscopic study.

A 66-year-old man (case 1) and a 71-year-old woman (case 2) showed systemic degeneration of the globus pallidus, substancia nigra, subthalamic nucleus, centrum medianum thalami and at times, superior colliculus in the midbrain. In the pallido-nigral system, neuronal loss was severe in both cases and an increase of pigment and granular spheroids was marked in case 2, less in case 1. Electron-microscopically, the spheroids consisted of aggregates of highly dense material, often membrane-bound, and varying amounts of groups of loosely packed filaments. Clinical symptoms were stereotyped and unique, showing severe akinesia, no rigidity in the limbs, no tremor but retropulsions, upward gaze palsy, dysarthria, dysphagia and later, nuchal stiffness. Nosological identification is discussed.