The case for duraplasty in adults undergoing posterior fossa decompression for Chiari I malformation: A systematic review and meta-analysis of observational studies

Abstract

BackgroundPosterior fossa decompression is carried out to improve passage of cerebrospinal fluid (CSF) in patients with symptomatic Chiari 1 malformations (CM1), but the extent and means of decompression remains controversial. Dural opening with subsequent duraplasty may contribute to clinical outcome, but may also increase complication risk. The aim of this systematic review and meta-analysis is to assess the effects of durotomy with subsequent duraplasty on clinical outcome in surgical treatment of adults with CM1. Data sources and study eligibility criteriaWe systematically searched MEDLINE, Embase and CENTRAL, and screened references in relevant articles and in UpToDate. Publications with previously untreated adults (>15 years) with CM1 with or without associated syringomyelia, treated in the period 1990–2013 were eligible. InterventionsPosterior fossa decompression with duraplasty (PFDD group) was compared to posterior fossa decompression with bony decompression alone (PFD group). ResultsThe search retrieved 233 articles. After the review we included 12 articles, but only 4 articles included posterior fossa decompression with both techniques. Only 2 out of 12 studies were prospective. The odds ratio (OR) for reoperation was 0.15 (95% CI 0.05–0.49) in the PFDD group compared to PFD (p=0.002). The OR of clinical failure at follow-up was 1.06 (95% CI 0.52–2.14) for PFDD compared to PFD (p=0.88). There was also no difference in syringomyelia improvement between techniques (p=0.60). The OR for CSF-related complications were 6.12 (95% CI 0.37–101.83) for PFDD compared to PFD (p=0.21). ConclusionThis systematic review of observational studies reveals higher reoperation rates after bony decompression alone, but clinical improvement was not higher after primary decompression with duraplasty. There are so far no high-quality studies that offer guidance in the choice of decompressive technique in adult CM1 patients. We think that a randomized controlled trial on this topic is both needed and feasible.