Clinical experience with the use of a shunt with an adjustable valve in children with hydrocephalus

Object. The goal of this study was to assess the value of making adjustments in the opening pressure of a shunt valve and to determine shunt survival in children and young adults in whom an adjustable valve was used to manage cerebrospinal fluid drainage. Methods. The authors conducted a single-center retrospective study of 158 children and young adults who had received 199 Codman Hakim programmable valves (noninvasively adjustable to settings in the range of 30-200 mm H2O). The mean age at which the patients underwent shunt implantation was 4.4 years (median 0.4 years, maximum 18 years); 94 patients were younger than 2 years of age, including 14 patients with a gestational age younger than 38 weeks at the time of implantation. In 84 (53.2%) of the 158 patients, valve pressure adjustment was required at least once (mean 1.3 times, maximum 16 times). Among the 202 adjustments made in patients the reason for adjustment was underdrainage in 74 adjustments (36.6%) and overdrainage in 119 (58.9%). The clinical status of the patient improved after 121 (69.1%) of 175 adjustments and after 58 (73.4%) of 79 minor adjustments (less than or equal to +/-20 mm H2O). The shunt infection rate was 13 (10.9%) of 119 patients. Shunt survival was 60.5% at 1 year, 47.1% at 2 years, and 43.9% at 3 years of follow-up review. Conclusions. Adjustment of the valve's opening pressure further improves outcome in pediatric patients.