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.