PERI-OPERATIVE RISK FACTORS FOR LONG TERM INTELLIGENCE IN CHILDREN WITH
POSTOPERATIVE CEREBELLAR MUTISM SYNDROME AFTER MEDULLOBLASTOMA SURGERY
Objective: 7-50% of children with medulloblastoma (MB) develop
postoperative cerebellar mutism syndrome (pCMS). pCMS has a short-term
negative impact on intelligence, but results on long-term outcomes are
contradictory. The aim of this study was to assess long-term effects of
pCMS in MB patients on aspects of intelligence (IQ) and its
perioperative risk factors. Methods: In this single centre retrospective
cohort study, 31 children with MB were included of which 14 had pCMS.
Peri-operative risk factors included brainstem invasion, vermis
incision, pre-and post-operative hydrocephalus, tumor size, duration and
severity of pCMS, neurological symptoms on day 10 after surgery, mean
body temperature (BT) on days 1-4 post surgery, and age at resection.
Age appropriate Wechsler Intelligence tests were assessed within a
structured follow up programme. Results: No significant differences in
IQ scores were found between pCMS and non pCMS groups. The pCMS group
had a clinically relevant difference of 10 points when compared to age
norms on verbal IQ (VIQ). Bilateral pyramidal and swallowing problems
were risk factors for lower performance in this group. In the overall
group, tumor size, younger age at surgery, and raised mean BT on days
1-4 post-surgery were negatively correlated with aspects of IQ.
Conclusions: We found a clinically significant reduction of VIQ in the
pCMS patient group. pCMS patients with a larger tumor size, younger age
at surgery, a higher mean BT in the first days after surgery, bilateral
pyramidal symptoms, and swallowing problems 10 days post-surgery are
more at risk for VIQ deficits at long-term.