Posterior fossa syndrome

Abstract Posterior fossa syndrome (PFS), also known as cerebellar mutism syndrome (CMS), is a distressing postoperative complication affecting children undergoing craniotomy for infratentorial tumors, most frequently medulloblastoma. It is characterized by a distinct latency period followed by mutism, profound emotional dysregulation, and a broad spectrum of cerebellar motor and cognitive deficits. Diffusion MRI and tractography have consistently shown that structural damage to the proximal efferent cerebellar pathway—specifically the dentato-rubro-thalamo-cortical tract within the superior cerebellar peduncle—is strongly implicated as the anatomical driver of PFS. Historical series favored the telovelar over the transvermian surgical approach, although recent prospective multicenter data demonstrate equivalent risks between the two techniques, shifting the neurosurgical focus toward meticulous surgical technique and minimizing damage to eloquent tissue around the fourth ventricle. Validated clinical scoring tools, such as the Posterior Fossa Syndrome Questionnaire, standardize clinical phenotyping and are making their way into clinical practice. Increasingly advanced risk prediction models allow for precise preoperative risk stratification based on objective imaging markers. Pharmacological interventions, including zolpidem and selective serotonin reuptake inhibitors, have shown limited efficacy in mitigating acute symptoms. Although near-universal clinical improvement occurs over time, long-term neurocognitive and motor sequelae remain highly disabling. Combining advanced neuroimaging, sophisticated risk modeling and meticulous microsurgical technique offers the best paradigm to shift the narrative of PFS from an expected complication to a preventable one.