Transient cerebellar mutism caused by bilateral damage to the dentate nuclei after the second posterior fossa surgery. Case report.

The authors report on the case of a 6-year-old boy who underwent resection of a midline cerebellar tumor. The boy was able to speak fluently after the operation. Magnetic resonance (MR) imaging showed that the right dentate nucleus had been partially removed along with the tumor, but that the left dentate nucleus remained with the residual tumor. A second operation was performed to remove the residue, after which the child suffered mutism. Three weeks post-surgery, he could only communicate through gestures. He started speaking I week later and regained normal speech 2 months after the operation. Final MR imaging revealed gross-total removal of the tumor and dentate nucleus on the injured left side. The cerebellar mutism was considered to have been caused by bilateral damage to the dentate nuclei and not by unilateral damage.