Low-pressure valves in hydrocephalic children: a retrospective analysis

PURPOSE: A series of 100 children under 2 years of age treated for hydrocephalus is described. All patients received a standard differential low-pressure (SD low) valve as the first cerebrospinal fluid (CSF) shunt treatment. The performance of this group during follow-up is analysed. METHODS: A retrospective cohort study was performed using the intern electronic health record from our hospital. Children younger than 2 years who underwent initial CSF shunt treatment with a SD low valve between 1998 and 2008 were eligible. RESULTS: Mean follow-up was 7 years. The majority of 81% (81 of 100) of the children did not receive an upgrade of pressure profile throughout follow-up. The first revision was done after a mean of 456 days (median, 64 days; min, 3; and max, 4,183). The 1-year survival rate of the CSF shunt in this cohort was 42%. In the relatively large group of myelomeningocele patients (37 of 100), only one patient developed symptomatic overdrainage. A total of 9% (9 of 100) of the children presented with symptoms of overdrainage. In 3% (3 out of 100) of these children, symptoms of overdrainage persisted, in spite of multiple valve mutations. During the total follow-up, 26% (26 of 100) of the patients had never received shunt revision surgery. Fifteen percent (15 of 100) of the children developed a shunt infection within the first year. CONCLUSIONS: The use of SD low valves in the youngest age group is effective in the majority of children. The aetiology of myelomeningocele appears to protect the patient from symptomatic overdrainage.