Diagnosis and Surgical Management of Chiari Malformation Type I

Introduction: Chiari malformation type I (CM I) is an abnormality of the craniovertebral junction affecting both adults and children. Its genesis is not clear however a reduced volume of the posterior fossa looks to play a significant role. We aim to report our experience in the diagnosis and the surgical management of CM I. Methods: A prospective study was conducted in our department over three years. We have included 50 patients diagnosed with CM I and surgically managed. We reviewed different criteria; epidemiological, clinical, and radiological before and after surgery to evaluate the efficiency of surgery in our patients. The data were analyzed using the Epidata software. Results: The most encountered preoperative symptoms were headaches majored by Valsalva in 100 ℅ and sensitive disorders (suspended sensory disorders in 32℅ and thermo-algesic dissociation in 32 ℅). Preoperative imaging showed that 66% have Chiari type I, 28% have Chiari type 1.5, and 06% have Chiari type 0. The bony and dural opening was performed in all patients. In 70% of patients, cerebellar tonsils were coagulated in 58% and resected in 12% of cases unilaterally. The thenar and hypothenar amyotrophies improved only in 10% of cases, and thermo-algesic dissociation improved in 63%. Conclusion: Surgical management for CM I is a safe and efficient procedure to relieve preoperative symptoms. Bony and dural is considered a good surgical technique. Additional maneuvers on tonsils should be added according to the preoperative finding after arachnoidal opening.