1293. Chiari Malformation: Posterior Fossa Decompression With or Without Duraplasty?

Authors: Alexander Perdomo-Pantoja, MD; Rajiv Iyer, MD; Alan Cohen, MD (Baltimore, MD)

Introduction: Posterior fossa decompression (PFD) is the treatment of choice for symptomatic Chiari I malformation (CIM) patients; however, controversy exists regarding specific surgical techniques needed to accomplish this goal. While a variety of methods have been described, an ongoing central debate exists regarding the need for duraplasty (PFDD) in addition to bony posterior fossa decompression for CIM. Methods: We performed a systematic review, including articles from 2000 to 2018, following the PRISMA statement, to study outcomes of CIM patients who underwent PFD with or without duraplasty. Information on demographic data, the type of procedure, study design, the presence of a syrinx, follow-up duration, and various clinical outcomes were collected. We conducted a meta-analysis to assess outcomes, such as clinical improvement, syringomyelia resolution, complications and reoperation rate. Results: Nine studies (including 212 and 315 patients undergoing PFD and PFDD, respectively) were included in the meta-analysis. Regarding clinical outcomes, PFDD showed higher clinical and syrinx improvement rates compared to PFD ( p >.05, <.05, respectively). PFDD yielded a higher complication rate than PFD ( p <.05), particularly in CSF fistula and aseptic meningitis ( p <.05). No differences were found in wound infection and pseudomeningocele rates. PFD showed a higher reoperation rate compared to PFDD ( p <.05). In PFD, reoperations were related to a lack of resolution of clinical symptoms and syringomyelia, while in PFDD, were due to persistence of symptoms, or repair of a CSF fistula. Conclusion: We found no significant difference in outcome with respect to postoperative clinical improvement, rate of wound infection, or pseudomeningocele occurrence between PFD and PFDD. Although the clinical response was similar between the groups, the rate of syrinx regression was higher in patients undergoing PFDD compared to PFD. And while the reoperation rate was higher in the PFD subgroup, complications as a whole were more frequent in patients undergoing PFDD.