Custom Shunt System for Increased Baseline Intracranial Pressure in a Patient with Idiopathic Intracranial Hypertension

Background: Standard treatment of idiopathic intracranial hypertension (IIH) involves reduction of intracranial pressure (ICP) to normal range, often via a ventriculoperitoneal shunt (VPS). We describe a case of a middle-aged man who presented with symptoms consistent with IIH. After ICP was normalized with a VPS, the patient had neurologic deterioration into a coma. He completely recovered after a month when his ICP was allowed to increase and remain above the normal range. Case Description: A 50-year-old man presented with daily headaches, visual loss (right > left), and increased lumbar opening pressure consistent with IIH. A VPS was inserted using a Strata II valve with a pressure setting of 1.5, lowering ICP into the normal range. The patient initially had a normal postoperative course, but then became comatose and developed imaging signs consistent with intracranial hypotension. A Codman Certas valve was placed at a setting of 7 and a distal slit-cut peritoneal catheter was used (as opposed to standard open output). This custom system drained at pressure >26 mm Hg based on intraoperative manometry. The patient tolerated this well and is currently planned for a gradual reduction in ICP with valve setting adjustments as an outpatient. Conclusions: In patients with chronic IIH, reduction to normal ICP may unexpectedly lead to encephalopathic changes. Personalized shunts may facilitate reduction of ICP to still elevated but tolerable levels in these patients.