Pre-operative cerebellar mutism secondary to vagus nerve schwannoma

Abstract

Cerebellar mutism, also known as 'posterior fossa syndrome,' is an uncommon condition often reported after posterior fossa tumour resection in the paediatric population. It is infrequently associated with other intrinsic cerebellar pathologies. We hereby report a rare case of pre-operative cerebellar mutism associated with an extrinsic posterior fossa lesion - vagus nerve schwannoma.

Cerebellar Mutism Syndrome in Children and Adults

“…To the best of our knowledge, preoperative posterior fossa mutism in adults has only been reported once in an unusual case of fourth ventricle vagus nerve schwannoma (Muthappan et al 2012).…”

“…While a recent, systematic review of the literature reported the incidence rate of POPCMS to range from 7 to 50 % of the studied population (Reed-Berendt et al 2014) 2 , the condition has only very occasionally been documented in adults following etiologically different posterior fossa lesions (e.g., Salvati et al 1991;Kai et al 1997;Ildan et al 2002;Akil et al 2006;Muthappan et al 2012;Mariën et al 2013a,b) or after focal damage of the brainstem (Messert et al 1966;Frim and Ogilvy 1995;D'Avanzo et al 1993). The age-related discrepancy in frequency of occurrence of CMS in children and adults is most often explained by (1) the higher incidence rate of posterior fossa tumors in children (Dolecek et al 2012;Massimino et al 2016), and (2) anatomical and functional, post-natal maturational factors, the incomplete myelination of the corticoponto-cerebello-thalamo-cortical loop rendering children more vulnerable to the impact of a cerebellar lesion (Ildan et al 2002).…”