Alexia without agraphia in a musician after transcallosal removal of a left intraventricular meningioma.

After a meningioma situated in the trigone of the left lateral ventricle was excised by the transcallosal approach of Kempe and Blaylock, a right-handed musician with a right hemianopsia developed alexia without agraphia. In contrast to previously reported cases of this syndrome arising from other etiologies, he was unable to read single letters or numbers. Neuropsychological studies at 42 and 126 days after operation also disclosed an inability to associate auditory or tactile stimuli with visually perceived material, whereas speech and verbal comprehension were intact. Although the alexia extended to musical notes, he could interpret other musical symbols (e.g., treble clef). Appreciation of rhythm and expressive musical ability were relatively preserved, although judgment of other musical features (including discrimination of pitch, duration, and loudness) was compromised. The findings suggest that alexia may occur as a consequence of the transcallosal procedure when a right hemianopsia is present. However, other linguistic abilities may be better preserved by the transcallosal approach to the ventricle than by a transcortical operation.