Tension Subdural Hygroma Following Resection of Posterior Fossa Tumour in a Child: A new clinico-radio-pathological entity.

Persistent hydrocephalus is common in children after resection of posterior fossa tumours. However, occurrence of subdural hygroma is very rare. We report the case of a 14-month-old child who presented at a paediatric neurology clinic in Muscat, Oman in 2021 who developed a tense subdural hygroma with stable hydrocephalus, in the early postoperative period, following posterior fossa tumour resection. We describe the distinctive clinical, radiological and pathological features associated with the development of a tense subdural hygroma. We also discuss the management by cerebrospinal fluid diversion, which includes either a ventriculoperitoneal or subduroperitoneal shunt. This unique condition is distinguished from external hydrocephalus by features that are critical to the management strategy.

Post-craniotomy leptomeningeal cyst: a new presentation of an old problem.

Leptomeningeal cyst (LMC) is a known complication of pediatric head injury but has not been described following a craniotomy other than for craniosynostosis. We present the case of a 20-month-old boy who underwent craniotomy for a traumatic epidural hematoma. There was an inadvertent tear of the dura which was repaired with a pericranial patch and dural sealant. The patient presented with a progressive surgical site swelling 5 months post-surgery and a CT scan revealed an LMC with elevation of the bone flap. He underwent re-exploration with watertight repair of the dural defect and rigid fixation of the bone flap. This iatrogenic LMC provides an opportunity to compare and confirm the pathogenesis vis a vis the more common spontaneous post-traumatic LMC. Our report highlights the importance of proper dural closure and bone fixation after craniotomy in children whose skulls are still growing.