The surgical strategy "CSF decompression" facilitates outcomes of adults with Chiari malformation type I: An observational, real-world, single center study of 528 patients.

ABSTRACT

OBJECTIVES: We designed this study to introduce the surgical strategy "CSF decompression" in treating Chiari malformation type I (CMI), and compared the "CSF decompression" strategy with other surgical strategies to provide a solid basis for patient counseling. METHODS: A total of 528 consecutive CMI patients who underwent surgical interventions from 2012 to 2022 were enrolled. The surgical strategy for these patients was bony and dural decompression (BDD), anatomical reduction of herniated tonsils (AR) or CSF decompression (CSFD). Short-term results were determined after 3 months; long-term outcomes were evaluated at last follow-up and at least 18 months. RESULTS: The CSFD strategy was independently associated with better long- or short-term primary outcomes than AR or BDD (P < 0.001). Compared with short-term, the long-term outcomes were better in CSFD patients (P = 0.035), but were worse in BDD patients (P = 0.03). Specific surgical techniques cannot affect the long- and short-term outcomes of CMI patients. CSFD provided better long-term syringomyelia improvement than short-term (181/218, 83% vs 169/218, 77.5%; P < 0.001). CONCLUSION: The "CSF decompression" surgical strategy, but not a specific surgical technique or operative method, was associated with favorable neurological outcomes in adult CMI patients. The surgical technique and operative method should be selected according to the characteristics of each patient and the intraoperative condition to normalized CSF circulation at CVJ. The intraoperative target maybe smoothly CSF flow, out from the fourth ventricle and in to the bilateral Luschka foramina, could be observed.