Functioning periods and complications of 246 cerebrospinal fluid shunting procedures in 208 children

To investigate the functioning periods and the causes of cerebrospinal fluid shunt failures, 246 shunts inserted in 208 children from October 1985 to August 1992 at the authors' institute were retrospectively reviewed. The mean age at shunt insertion was 4.0 years and the reasons for the shunting procedures were congenital hydrocephalus (47.6% per procedure), tumor-associated hydrocephalus (21.1%), postmeningitic hydrocephalus (11.8%), congenital cyst (10.6%) and others (8.9%). All except 2 were shunted to the peritoneal cavity. Forty-five operations for shunt failure were done (18.3%) during the follow-up period (mean, 32 months). The functioning (shunt survival) rates at 6, 12, 24 and 36 months after surgery were 91.6%, 86.6%, 83.6% and 82.9%, respectively. The complications were mechanical malfunction (12.2%), infection (4.1%), subdural fluid collection which required drainage (1.6%) and migration (0.4%). About half of the mechanical malfunctions and infections which had occurred during the follow-up period were within 6 months and 2 months after surgery, respectively. There was no shunt-related mortality. These chronological data should be considered in the planning of follow-up schedules.