Transient mutism following posterior fossa surgery in children

We report 3 patients, ages 5, 9 and 13 years, with mutism following posterior fossa surgery (PFS). All presented with headache of 10-180 days duration, excellent premorbid learning performance and paucity of neurologic signs. Radiographic studies demonstrated large posterior fossa tumor occupying the fourth ventricle, and hydrocephalus, leading to gross total resection of the tumor. Within 24-48 hr, all patients were mute. None had problems with swallowing and coughing. All were able to nod "yes or no," follow commands, point to body parts, and make their wants known by gestures. Jaw, gag, snout and palmomental reflexes were normal. CT scan and MRI Brain showed no cerebral hemispheric lesions. All children regained speech although dysarthric, within 5-12 weeks. Twenty-two previously reported cases are similar to ours. We conclude that this post-surgical mutism syndrome is unique and must be differentiated from aphemia, Broca's aphasia, hysterical mutism and elective mutism. The cerebellum, in a way not yet understood, does play a role in speech production.