Total mesencephalic "locked-in" syndrome. A case report and review of the literature.

A 63-year-old man suddenly fell in a state of apparent coma. An electroencephalogram (EEG) performed at a local hospital revealed the maintenance of a reactive alpha rhythm over the posterior regions of the scalp, allowing a diagnosis of alert coma. The persistence of minimal degrees of alertness and ability to communicate made the clinical picture classifiable as a "locked-in" syndrome (LIS). Bilateral ptosis and complete ophthalmoplegia oriented towards a total mesencephalic form of LIS. Computed tomography (CT) and magnetic resonance imaging (MRI) of the brain showed pathological findings at mesencephalic level. Such findings were insufficient to explain the clinical picture.