TRANSIENT CEREBELLAR MUTISM

The term ''cerebellar mutism'' refers to a specific disorder in which a complete but transient loss of speech, followed by dysarthria, occur s following resection of intrinsic posterior cranial fossa tumors or c erebellar hemorrhages, or upon trauma. Although it is well known that the :lack of long-tract findings and cranial nerve (CN) involvement is the rule, the pathophysiology of cerebellar mutism has not been clear ly elucidated. A review of the relevant literature disclosed 93 patien ts with this condition, the majority of these being in the pediatric a ge group. The neuropathological findings were as follows: 57 primitive neuroectodermal tumors (PNET), 19 astrocytomas, 10 ependymomas, 5 vas cular malformations, 1 metastatic tumor, and 1 traumatic injury. The i nterval before the onset of mutism ranged from 0 to 168 h (mean 40.9 h ). The mutism lasted from 1 to 168 days (mean 37.6 days). Subsequent d ysarthria was present in 75 (80%) of the 93 patients. In this article, some specific recent illustrative reports are presented, and the conc ept of the role of the cerebellum in language and cognition is discuss ed. With these data as our point of departure, various hypotheses that have been advanced to explain the pathogenesis of this transient spee ch disorder are analyzed. The findings of the study suggest that the c ause of the cerebellar mutism is the ischemia caused by vasospasm, as it usually developed after a latent period.