Long-term outcome of hydrocephalus management in myelomeningoceles

Background. The cerebrospinal fluid (CSF) shunt remains an important ongoing management problem in myelomeningocele (MMC) patients. We reviewed the long-term shunt treatment outcome in a prospectively followed group of MMC patients from a single institution. Method. Patients prospectively entered into a hydrocephalus database with a diagnosis of MMC from the years 1987 to 1996 were selected. All data was verified from the medical records and additional details about the shunt surgery were collected. The outcome of shunt failure was categorized as shunt obstruction, shunt infection, presence of loculated ventricles, overdrainage, and other. All deaths were recorded and causation identified. Univariate analysis for shunt failure risk factors was accomplished using Log rank statistics. Multivariable analysis was performed for each repeated failure level using a conditional Cox regression model. Results. One hundred and twenty (64%) out of 189 MMC patients experienced a first shunt failure with a median time of 303 days; 29 (24%) of the failures were due to shunt infection (the procedure infection rate being 15%). Sixty-one patients experienced a second shunt failure, 38 a third and 36 had four or more. Multivariable analysis of risk factors failed to demonstrate any clear risk factors for either first or subsequent shunt failure. Fifteen patients died, 13 from either shunt or Chiari 1 complications. Conclusion. Shunt complications remain an important cause of morbidity and mortality in MMC patients, particularly shunt infection.