Paradoxical ventriculomegaly due to low-pressure hydrocephalus, a rare complication of the treatment of a trapped fourth ventricle: Case report.

In this paper, we describe the rare phenomena of descending transtentorial herniation and paradoxical ventriculomegaly due to low pressure hydrocephalus. This resulted as a complication of treatment in a 14year old male patient, who had undergone multiple ventriculo-peritoneal shunt placements for hydrocephalus after resection of pilocytic astrocytoma. We discuss the etiology of this rare complication and our strategy for treatment. We emphasize the need for strategic placement of programmable shunts to avoid over shunting and associated complications such as tentorial herniation.