Cerebellar mutism in adults after posterior fossa surgery: a report of 2 cases.
BACKGROUND
Mutism has been associated with injury to midline cerebellar structures secondary to degenerative disease, tumors, hemorrhage, or surgery. Typically, cerebellar mutism syndrome (CMS) has been seen in children and only rarely described in adults after surgery of the posterior fossa. This syndrome typically arises 48 hours after the initiating event and resolves approximately 7 to 8 weeks later. Characteristics of CMS include complete absence of speech without impaired consciousness, other cranial nerve deficits, or long tract signs.


METHODS
The authors report on 2 patients each of whom developed cerebellar mutism after tumor resection using a posterior fossa approach. The first patient underwent gross total resection of a pineal region tumor via a supracerebellar approach. The second patient underwent posterior fossa decompression for a left cerebellar hemispheric renal cell carcinoma metastasis with adjacent hemorrhage. One patient displayed a variant of cerebellar mutism with severe ataxic dysarthria without complete absence of speech, whereas the other demonstrated frank mutism. After neuroimaging studies confirmed the absence of a surgically treatable postoperative cause for the patients' symptoms, they were managed in a supportive fashion (eg, speech therapy) and improved within 3.5 months and 1 year, respectively.


CONCLUSIONS
It is paramount that neurosurgeons be aware of cerebellar mutism with regard to its very rare occurrence in adults, its time of onset, and typical self-limiting course.
Sherman
Jonathan H
JH
Department of Neurological Surgery, University of Virginia, Charlottesville, VA 22908, USA. js2bx@virginia.edu
Sheehan
Jason P
JP
Elias
W Jeffrey
WJ
Jane
John A
JA
D000328:Adult; D001932:Brain Neoplasms / Q000473:pathology / Q000601:surgery*; D002292:Carcinoma, Renal Cell / Q000503:physiopathology / Q000556:secondary / Q000601:surgery*; D002528:Cerebellar Neoplasms / Q000503:physiopathology / Q000556:secondary / Q000601:surgery; D002531:Cerebellum / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D003388:Cranial Fossa, Posterior / Q000601:surgery*; D019299:Decompression, Surgical / Q000009:adverse effects; D003884:Dermoid Cyst / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009155:Mutism / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D009364:Neoplasm Recurrence, Local; D018365:Neoplasm, Residual; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D010871:Pinealoma / Q000473:pathology / Q000601:surgery; D011183:Postoperative Complications / Q000209:etiology / Q000473:pathology; D016634:Radiosurgery; D011878:Radiotherapy; D016896:Treatment Outcome