Tonsillar herniation and cervical syringomyelia due to postoperative meningitis in case of pineal region epidermoid.

The occurrence of tonsillar herniation and syringomyelia in association with tumor-induced obstructive hydrocephalus has been described in literature. In midline tumors, the symptomatology is predominantly due to hydrocephalus and resultant tonsillar herniation, but the treatment is primarily directed towards the tumor. A case of a pineal region epidermoid in a 17-year-old boy - in whom postoperative meningitis resulted in hydrocephalus, symptomatic tonsillar herniation and cervical syringomyelia - is presented here. Although the tumor was resected and cerebrospinal pathways were established, a ventriculoperitoneal shunt insertion was required for persistent symptomatic hydrocephalus. At serial follow-up after 2 years, the patient was asymptomatic and MR imaging showed a reduction in size of the cervical syrinx, but there was no significant ascent of the tonsils. The occurrence of tonsillar herniation and syringomyelia following postoperative meningitis in a case of pineal region epidermoid is uncommon and has not been reported till now. Cerebrospinal diversion procedure will most often be required in such a situation for symptomatic relief. The resolution of tonsillar herniation and syringomyelia may not always be complete on serially documented neuroimaging in such a situation. Stabilization of the previously progressive neurological course is the realistic goal. The need for an additional surgical procedure for associated tonsillar herniation and syringomyelia is advocated only if there is progressive neurological worsening.