Ns-32preoperative Risk Factors for Developing Cerebellar Mutism Syndrome in Children With Posterior Fossa Tumors

Abstract

PURPOSE: Cerebellar mutism syndrome (CMS) is a common complication of posterior fossa surgery in children. We have compared the neuropsychological, emotional and behavioral profiles in children before and after removal of the posterior fossa tumor. METHODS: We performed clinical neuropsycological examination of 91 patients (47.2% boys, 52.8% girls) aged 4 -17, who were undergoing primary surgical treatment of tumors of cerebellum, brain stem and 4 th ventricle. The patients were classified into 3 groups according to the severity of postoperative neuropsychological defect: Group 1 -with CMS., Group 2 -with cerebellar cognitive affective syndrome without speech loss (CCAS), Group 3 -no complex neuropsychological symptoms and signs. We used neuropsychological scales for children of different age groups by E.G. Simernitskaya, A.V. Semenovich; Yale-Brown obsessive compulsive scale, Aichenbach child behavior checklist, Zakharov neurotization scale. RESULTS: Children in CMS group (25.3%) before surgery showed significant difference from other groups on the following factors of neurotization and obsessive-compulsive disorder, dysprosody, impaired visual memory, decreased dynamics, becoming exhausted, and dyssomnia (p , 0/05). Significant risk factors for CMS included midline and paramedian localization of tumor, high-grade (III-IV), marked hydrocephalus. The neuropsychological status in the CCAS Group (20.9%) was intact, and the patients had high neurotization level with obsessive compulsive traits and dyssomnia (insomnia). These symptoms and signs tended to progress following surgery in the form of psychomotor agitation with pathopsychological and psychosensorial elements. Children in Group 3 (53.8%) had moderate emotional lability, decreased dynamics, impaired praxis and visual-motor coordination which tended to regress after the process had been eliminated. CONCLUSION: The revealed neuropsychological symptom complex of irritation of the brain stem and the limbic system, as well as of insufficiency of postfrontal and secondary parietal-temporal-occipital areas of the cortex in children with median anaplastic Posterior Fossa Tumor might be indicative of the disturbance of the dento-thalamo-cortical pathways and be a significant risk factor for developing CMS.