Cerebrospinal fluid-related complications with autologous duraplasty and arachnoid sparing in Type I Chiari malformation

OBJECTIVE: Although there is a current consensus that Type I Chiari malformations (CM-1) should be treated only in the setting of symptomatic disease, significant controversy surrounds the most appropriate surgical procedure. Recent enthusiasm for osseous decompression without duraplasty is supported by the purportedly lower morbidity of this approach. Precise rates of morbidity with duraplasty, however, have not been reported. This study is intended to assess the cerebrospinal fluid-related morbidity associated with a patient population treated uniformly with autologous duraplasty for symptomatic CM-1. METHODS: A review of one surgeon's practice (MMS) from 1997 to 2007 identified patients treated for symptomatic CM-1 with osseous decompression and autologous duraplasty. A retrospective chart review was then performed for these patients with an emphasis on cerebrospinal fluid-related complications. RESULTS: Forty patients were treated for CM-1 with decompression and autologous duraplasty. Twenty-four patients presented with a preoperative syrinx. The mean age was 13.3 years, and the median age was 12.9 years (range, 3.3-45.8 yr). The mean follow-up period was 11.4 months (range, 1-101 mo). There was no mortality associated with the procedure. Clinical response was observed in 91.8% of patients, with 70.2% experiencing complete symptomatic resolution and 21.6% experiencing partial improvement. Two patients (5.4%) had persistent symptomatic syringomyelia requiring syringo-subarachnoid shunting. There was an overall morbidity rate of 2.5% due to one pseudomeningocele treated with a single percutaneous tap. There were no incidences of cerebrospinal fluid leak, meningitis, or postoperative hydrocephalus. CONCLUSION: The cerebrospinal fluid-related morbidity associated with autologous duraplasty for CM-1 in a uniformly treated population is negligible. These results challenge the current rationale for a less aggressive surgical approach to CM-1.