PREVENTION

There are no certain ways to prevent the post-operative pediatric CMS from developing. Pre-operative corticosteroids have been recommended to reduce peritumoral edema, which may decrease nausea and vomiting and improve appetite and neurological symptoms. Intra-operative electrophysiological monitoring of the lateral rectus and facial muscles may help when the surgeon is working near the 6th cranial nerve [1], and surgical access and technique seem to play an important role.  Electrophysiological monitoring, the avoiding of vermian dissection in favor of a telovelar approach, as well as minimal use of retraction and ultrasonic aspiration at the Children's National Medical Center in Washington decreased the incidence of the syndrome from 39% to 13% over an 8 year period [2]; another institute similarly reported lower incidence after abandoning vermal split [3]. Piecemeal removal as opposed to en block tumor removal has been advocated [4], as is avoiding damage to the right cerebellar hemisphere since it can be deleterious to cognitive functioning [5].  Navigated intra-operatie ultrasonography dramatically reduced the incidence of the post-operative pediatric CMS at one center, reportedly due to less retraction force on the cerebellar nuclei, vermis and superior cerebellar peduncles, minimal damage to normal cerebellar tissue and less post-operative edema [6]. As with all forms of surgery, the more experienced the surgeon is, the better. Further research is highly warranted, and a prospective multicenter study of surgical methods, medication and genetics is underway in the Nordic countries and the USA (see under Research - current studies).

Links to:

Definitions, Incidence, Symptoms, Anatomy, Pathophysiology, Imaging findings, Risk factors, Treatment

1. Albright AL, Pollack IF, & Adelson PD (2008). Principles and Practice of Pedatric Neurosurgery (Second Edition) New York: Thieme

2. Siu A, Wells EM, Snyder K, Defreitas T, Myseros JS, Yaun AL, Magge S, Oluigbo C, Keating RF (2013) Cerebellar Mutism Syndrome: A significant reduction in incidence and risk factor analysis in children with medulloblastoma. Presented at International Society of Pediatric Neurosurgery Annual Meeting, Mainz, Germany, September 30, 2013, publication in prep. Personal Communication

3. Callu D, Viguier D, Laroussinie F, Puget S, Boddaert N, Kieffer V et al. (2009). Cognitive and academic outcome after benign or malignant cerebellar tumor in children. Cogn Behav Neurol 22: 270-278

4. Aguiar PH, Plese JP, Ciquini O, Marino R (1995). Transient mutism following a posterior fossa approach to cerebellar tumors in children: a critical review of the literature. Childs Nerv Syst 11: 306-310

5. Puget S, Boddaert N, Viguier D, Kieffer V, Bulteau C, Garnett M et al. (2009). Injuries to inferior vermis and dentate nuclei predict poor neurological and neuropsychological outcome in children with malignant posterior fossa tumors. Cancer 115: 1338-1347

6. El Beltagy MA, Atteya MM (2013). The benefits of navigated intraoperative ultrasonography during resection of fourth ventricular tumors in children. Childs Nerv Syst [Epub ahead of print]