(Kiosk 6) Postoperative Pediatric Cerebellar Mutism Syndrome, Cognitive, and Functional Improvement in a Patient with WHO Grade 1 Pilocytic Astrocytoma After Bromocriptine Initiation: A Case Report

Case Diagnosis: Cerebellar Mutism Syndrome

Case Description or Program Description: 5-year-old healthy male presented with 6-month onset of dysconjugate gaze, horizontal and vertical nystagmus, associated with morning emesis, decreased coordination, and gait instability. MRI brain revealed heterogeneous cystic posterior fossa mass with associated 4th ventricle obstruction, brain stem compression, and ventriculomegaly. He underwent subtotal resection of the tumor and external ventricular drain placement. Pathology demonstrated grade 1 pilocytic astrocytoma without evidence of germline mutation. Post-operative impairments included: multiple cranial nerve palsies (left VII, V2, V3, VI), up-gaze palsy with horizontal nystagmus, mutism, flat affect, emotional lability, left hemiparesis, and dysphagia. Admitted to inpatient rehabilitation. Given persistent impairments and slowed processing, bromocriptine was initiated.

Setting: Inpatient Rehabilitation

Assessment/Results: Following bromocriptine initiation, he had dramatic improvement with resolution of emotional lability, initiation of dysarthric speech, and improved participation in gross and fine motor activities in therapy though continued to have dysmetria worse on right than left. Neuropsychology assessment at discharge found average range verbal abilities, attention and working memory but persistent difficulties with higher level visual-spatial reasoning, heightened visual details, and tasks involving psychomotor speed.

Discussion (relevance): Cerebellar mutism syndrome is a commonly described phenomenon occurring after lesions to the dento-thalamic-cortical pathway often in setting of large midline cerebellar tumors, trauma, inflammation, or stroke effecting the dentate nuclei and superior cerebellar peduncle. It is hallmarked by absence of speech acutely with initial recovery of dysarthric speech. There is no established treatment with only case reports trialing steroids, fluoxetine, bromocriptine, and zolpidem. Patients with mutism lasting greater than 4 weeks are at increased risk of persistent speech and language impairments. Because of this, it is important to characterize medication options such as bromocriptine and neuro-psychological improvements associated with treatment.

Conclusions: Bromocriptine was found to be a safe and effective treatment for cerebellar mutism syndrome when coupled with a comprehensive inpatient rehabilitation program.