Long term follow-up of shunted idiopathic normal pressure hydrocephalus patients: a single center experience

Idiopathic normal pressure hydrocephalus (iNPH) is a condition characterized by gait disturbance, dementia and/or urinary incontinence and enlarged ventricular system due to disturbance of cerebrospinal fluid (CSF). This study aims to describe the long-term experience with patients with iNPH submitted to ventriculoperitoneal shunt (VPS) with the programmable valve STRATA (R) (Medtronic). We prospectively selected a cohort of patients with a diagnosis of iNPH from January 2010 to April 2013 in a Brazilian tertiary hospital. All patients underwent clinical evaluation, which consists of the Mini-Mental State Examination and Time Up and Go tests and the application of Japanese Scale for Idiopathic Normal Pressure Hydrocephalus in three stages: prior to the TT, 3 h after the TT and 72 h after the TT. Fifty patients were submitted to VPS and followed. There were 32 men and 18 women. Mean age was 77.1 with standard deviation of 10.9. Follow-up time ranged from 96 to 120 months, with mean of 106 months. After 1 year of follow-up, 42 (83%) patients presented with clinical improvement, decreasing to 62% of patients at mid-term follow-up and 38% of patients at late follow-up. Complications occurred in 18% of subjects, needing reoperation in 16%. Our results show relevant clinical impact of shunting in iNPH patients, decreasing over time. Complications should not be underestimated, reaching up to 18% and demanding reoperation in 16% of cases. Thus, although much has been improved with current shunt technology, it is still important to consider the drawbacks of treatment.