Effectiveness of Cerebellar Tonsillectomy Treatment for Revision Chiari Malformation Surgery: a series of 63 patients

Fan Yuan; Chenghua Yuan; Dingran Li; Pingchuan Xia; Jian Guan; Yueqi Du; Can Zhang; Zhenlei Liu; Kai Wang; Wanru Duan; Zuowei Wang; Xingwen Wang; Hao Wu; Zan Chen; Fengzeng Jian

doi:10.1016/j.wneu.2025.123690

Effectiveness of Cerebellar Tonsillectomy Treatment for Revision Chiari Malformation Surgery: a series of 63 patients

World Neurosurg. 2025 Jan 22:123690. doi: 10.1016/j.wneu.2025.123690. Online ahead of print.

Authors

Fan Yuan¹, Chenghua Yuan¹, Dingran Li¹, Pingchuan Xia², Jian Guan¹, Yueqi Du¹, Can Zhang¹, Zhenlei Liu¹, Kai Wang¹, Wanru Duan¹, Zuowei Wang¹, Xingwen Wang¹, Hao Wu¹, Zan Chen¹, Fengzeng Jian³

Affiliations

¹ Department of Neurosurgery, Xuanwu Hospital, Capital Medical University; Spine Center, China International Neuroscience Institute (CHINA-INI); Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University; Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI); National Center for Neurological Disorders, Beijing, CHINA.
² Xuanwu Hospital, Capital Medical University.
³ Department of Neurosurgery, Xuanwu Hospital, Capital Medical University; Spine Center, China International Neuroscience Institute (CHINA-INI); Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University; Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI); National Center for Neurological Disorders, Beijing, CHINA. Electronic address: jianfengzeng@xwh.ccmu.edu.cn.

PMID: 39855550
DOI: 10.1016/j.wneu.2025.123690

Abstract

Background: Revision surgery for patients with persistent, recurrent, or progressive syringomyelia following foramen magnum decompression (FMD) for Chiari malformation I-syringomyelia (CM-SM) is not uncommon and presents both strategic and technical challenges.

Methods: We conducted a retrospective study including all patients who underwent revision Cerebellar Tonsillectomy (CTL) for CM-SM between 2003 and 2023. Additionally, we performed uni- and multivariate analyses to identify possible factors contributing to failed CTL outcomes.

Results: Sixty-three consecutive patients (13 males; average age 45.86±11.18 years) underwent surgical treatment for persistent (n=29), progressive (n=21), or recurrent (n=13) syringomyelia, with an average interval of 65.57±73.33 months (range: 3-480 months) between the two surgeries. Factors significantly associated with the effectiveness of the revision CTL included dural incision and tonsil manipulation during the first surgery, severe intradural adhesions during the revision CTL, and spinal cord atrophy before the revision CTL. Multivariate logistic regression revealed that dural incision (P=0.031, OR=6.779, 95%CI (1.187∼38.719)), tonsillar manipulation (P=0.037, OR=7.432, 95%CI (1.131∼48.835)), and severe intradural adhesions (P=0.030, OR=11.465, 95%CI (1.264∼103.967)) constituted risk factors significantly statistical associated with prognosis outcomes. Long-term follow-up (average 18.75±6.86 months, range: 12-72 months) of revision CTL demonstrated clinical stabilization in 55.6% of cases for at least 1.5 years. The complication rate for revision CTL was 14.3% (n=9).

Conclusion: Dural incision and tonsillar manipulation during the first surgery, spinal cord atrophy prior to revision CTL, and severe intradural adhesions during revision CTL are significant risk factors associated with poor prognosis in revision surgery for CM-SM.

Keywords: CM-SM; effectiveness; revision findings; revision surgery; syringomyelia.