Fibromatosis of dura presenting as infantile spasms.

A 6-month-old boy developed emprosthotonic infantile spasms and right hemiparesis. CT scan revealed a large mass related to a distended right temporal horn which on craniotomy proved to be a hard white tumour of the tentorium cerebelli which could be only incompletely resected. Microscopically and ultrastructurally, this lesion proved to be a typical fibromatosis containing myofibroblasts which invaded the brain. The child made an excellent recovery and is well a year after surgery. This case is another example which argues for full investigation of cases of infantile spasms which usually carry such a dismal prognosis.