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Development and application of a diagnostic and severity scale to grade post-operative pediatric cerebellar mutism
Federica S Ricci1,2, Rossella D'Alessandro3, Alessandra Somà3
1Section of Child and Adolescent Neuropsychiatry, Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy. federica.ricci@unito.it.
Insights
A new scale helps assess pediatric cerebellar mutism syndrome (CMS) after posterior fossa tumor surgery. This tool aids in grading severity and predicting outcomes for affected children.
Area of Science:
- Pediatric Oncology
- Neuroscience
- Clinical Assessment Tools
Background:
- Post-operative pediatric cerebellar mutism syndrome (CMS) affects approximately one-third of children after posterior fossa tumor (PFT) surgery.
- CMS is characterized by delayed speech reduction and emotional lability, often with hypotonia and dysphagia.
Purpose of the Study:
- To develop and validate a diagnostic scale for grading the duration and severity of pediatric CMS.
- To identify risk factors associated with CMS development and severity.
Main Methods:
- A Post-Operative Pediatric CMS Survey was administered to 30 children (aged 1-17) post-PFT surgery.
- Patients were evaluated for 30 days post-CMS onset or until symptom remission, with severity classified at day 30.
Main Results:
- CMS occurred in 43% of patients, with 38% experiencing severe symptoms.
- Longer symptom duration and greater initial severity predicted worse outcomes at 30 days.
- Midline tumor location and age under 5 years were identified as risk factors for CMS.
Conclusions:
- The proposed scale is a practical tool for assessing CMS severity and monitoring its course.
- The scale facilitates early prognostic stratification to guide treatment decisions for pediatric CMS patients.
Abstract:
The post-operative pediatric cerebellar mutism syndrome (CMS) affects about one-third of children and adolescents following surgical removal of a posterior fossa tumor (PFT). According to the Posterior Fossa Society consensus working definition, CMS is characterized by delayed-onset mutism/reduced speech and emotional lability after cerebellar or 4th ventricle tumor surgery in children, and is frequently accompanied by additional features such as hypotonia and oropharyngeal dysfunction/dysphagia. The main objective of this work was to develop a diagnostic scale to grade CMS duration and severity. Thirty consecutively referred subjects, aged 1-17 years (median 8 years, IQR 3-10), were evaluated with the proposed Post-Operative Pediatric CMS Survey after surgical resection of a PFT and, in case of CMS, for 30 days after the onset (T0) or until symptom remission. At day 30 (T1), CMS was classified into mild, moderate, or severe according to the proposed scale. CMS occurred in 13 patients (43%, 95% C.I.: 25.5-62.6%), with mild severity in 4 cases (31%), moderate in 4 (31%), and severe in 5 (38%). At T1, longer symptom persistence was associated with greater severity (p = 0.01). Greater severity at T0 predicted greater severity at T1 (p = 0.0001). Children with a midline tumor location and those aged under 5 years at diagnosis were at higher risk of CMS (p = 0.025 and p = 0.008, respectively). In conclusion, the proposed scale is a simple and applicable tool for estimating the severity of CMS at its onset, monitoring its course over time, and providing an early prognostic stratification to guide treatment decisions.
