Pontine tegmentum hematoma: a case report with the "one-and-a-half" syndrome without pyramidal tract deficit.

The author reports the case of a 54-year-old male patient with a pontine hematoma and with the one-and-a-half syndrome, cerebellar ataxia and no signs of pyramidal tract involvement. The absence of involvement of the pyramidal tract in the case reported herein is likely due to variation in the vascular anatomy of the pons. The pathophysiologic mechanisms of the one-and-a-half syndrome and of the clinical findings recorded are discussed.