Posterior Fossa Decompression with Duroplasty for Treatment of Chiari Type I Malformation: Surgical Technique, Clinical and Radiological Outcome

Background: Surgical treatment of Chiari type I malformation by posterior fossa decompression is the nearly agreed widespread procedure, however, many surgical details are still controversial. Objective: This retrospective study aims to evaluate the impact of posterior fossa decompression, arachnoid dissection and duroplasty in treatment of symptomatic Chiari type I malformation on both clinical and radiological outcomes. Patients and Methods: Sixteen patients six males and ten females (M: F=1:1.6), ranging from 21-52 yrs (mean age 34 yrs), were operated upon at Cairo University Hospitals between June 2011 and May 2014. Syringomyelia was associated in nine patients (56.3%). The most common presenting symptoms were headache (100%), neck pain (87.5%) and limb parasthesias (75%). Results: At the end of a year of follow up, excellent clinical outcome was achieved in twelve patients (75%), good in two patients (12.5%), fair in one patient (6%) and poor in one patient (6%). Radiological follow up revealed restoration of normal tonsillar level in fifteen patients (94%) with one case of nonsymptomatic cerebellar subsidence. Syringomyelia showed marked reduction in 67% of cases. All were associated with excellent clinical outcome. Complications were encountered in four patients (25%) without mortalities.Conclusion: Posterior fossa decompression, arachnoid dissection and duroplasty is an effective modality for treatment of Chiari type I malformation with or without Syringomyelia, and is associated with favorable clinical outcome and low morbidity.