[Pure sensory stroke due to midbrain hemorrhage--case report].

We had a case of patient with pure sensory stroke which was caused by the rapture of a cryptic angioma located on the mesencephalon. The patient was a 41-year-old woman. She visited our clinic with sudden onset of numbness in the left hand, arm, trunk, leg, and face, and of hyposmia of the left side on arising. CT scans revealed a small hematoma with calcification located on the right dorsal mesencephalon, which diminished in size correlating with her recovery of the sensation. Her symptoms were considered to be caused by this hematoma which destroyed only the trigeminothalamic and the spinothalamic tracts excluding the superior colliculi, oculomotor nucleus, and the medial leminiscus. By angiography we failed to demonstrate a cause of the hemorrhage, but the presence of a cryptic angioma was suggested, because the post angiographic CT scan exhibited enhancement of the lesion. Her olfactory sensation was also restored accompanied with the recovery of the superficial sensation, therefore the hyposmia seemed to be due to the damage of the trigeminothalamic tract.