Introduction: Obesity is a known risk factor for developing pseudotumor. It is unclear based on existing data if obesity is associated with shunt failure in patients with idiopathic intracranial hypertension. We sought to investigate and quantify these cases.
Methods: Obesity is a known risk factor for developing pseudotumor. According to the WHO classification, type I obesity is defined as a BMI 25-30, type II obesity as BMI 35-40, and type III obesity as BMI=40. It is unclear based on existing data if obesity is associated with shunt failure in patients with idiopathic intracranial hypertension. We sought to investigate and quantify these cases.
Results: Twelve patients underwent ventriculoperitoneal shunt placement and 6 patients had lumboperitoneal shunts. We stratified patients according to BMI: 25-30 (pre-obesity): 3 patients; 30-35 (type I) 3 patients; 35-40 (type II): 5 patients; =40 (type III): 8 patients. Twelve patients (63%) had an initial VPS with 75% (9/12) having persistent symptoms despite shunting, 90% of them having a BMI=35.Three of the patients with a VPS required conversion to an LP shunt, all with a BMI =35. Only one patient who was converted had improvement in symptoms. Seven patients (32%) had an initial LP shunt; 75% of patients with persistent symptoms despite initial LP shunting had a BMI =35. One patient with type I obesity required conversion to VPS, not improving after conversion. Five of 12 (42%) VPS patients required revision, 80% of these patients had a BMI =35.
Conclusions: Obesity was associated with persistent symptoms despite CSF diversion irrespective of the type of initial shunt placed and conversion to a different type of shunt. A higher revision rate was seen in patients with BMI=35. Our data suggest that obese patients with pseudotumor, particularly with a BMI=35, are difficult to treat with CSF diversion. Perhaps alternate methods of treatment should be investigated.
Patient Care: My research will improve patient care by helping physicians realize the importance of controlling obesity and the role it plays in idiopathic intracranial hypertension.
Learning Objectives: By the conclusion of this session, participants should be able to (1) describe the importance of obesity in evaluating and treating idiopathic intracranial hypertension (2) identify those patients who are at risk for shunt failure.