Chiari Malformation Type I and Syringomyelia: Outcomes of Arachnoid-Preserving Surgical Technique

BACKGROUND Chiari malformation type 1 occurs when the cerebellar tonsils are pushed into the spinal canal, which can result in syringomyelia. This retrospective study from a single center evaluated outcomes in 89 patients with Chiari malformation type-I (CM-I) and syringomyelia treated with an arachnoid-preserving technique between 2016 and 2023. MATERIAL AND METHODS A retrospective analysis was conducted at a tertiary referral center, involving 88 adult patients and 1 adolescent patient aged 14 to 61 years, with diagnosis by MRI and treated for CM-I with syringomyelia between 2016 and 2023, using the arachnoid-preserving technique. Patients' demographics, clinical presentations, radiological findings, surgical details, and postoperative outcomes were analyzed. Primary outcomes were postoperative complications, while secondary outcomes included neurological improvement (measured by the visual analog scale) and patient satisfaction. RESULTS The study included 89 patients, with 69 female (77.5%) and 20 male (22.5%) patients. A significant reduction in syrinx size was observed in 83.3% of patients, with complete resolution in 16.7%. Mean surgery duration was 90 min, and average hospitalization duration was 2.75 days. All patients experienced significant improvements in neurological symptoms, such as headache, neck pain, numbness, and weakness. High levels of patient satisfaction were reported, with 100% of patients satisfied with their surgical outcomes. The incidence of complications, such as cerebrospinal fluid leakage and arachnoiditis, was notably lower than those by traditional methods. CONCLUSIONS The linear, arachnoid-preserving suboccipital decompression technique offers a safe, effective, and rapid alternative for managing CM-I with syringomyelia, demonstrating a notable reduction in postoperative complications and significant improvements in neurological outcomes.