Comparison decompression by duraplasty or cerebellar tonsillectomy for Chiari malformation-I complicated with syringomyelia

Objective: The current study aimed to assess the two surgical procedures of posterior fossa decompression (PDF) in treating Chiari malformation type I (CM-1) complicated by syringomyelia (SM), and to evaluate the postoperative complications, surgical effects and prognosis.

Patients and methods: A retrospective study was performed on 115 adult CM-I patients undergoing surgical treatment from November 2013 to November 2016 in a single comprehensive hospital. These patients underwent the surgical procedure of either posterior fossa decompression with duraplasty (PFDD) or posterior fossa decompression combined with the resection of tonsils (PFDRT) by five experienced neurosurgeon in a single center. The clinical outcomes of these two surgical procedures were evaluated through comparing the clinical data before and 6 months after the operation.

Results: A total of 115 patients, including 35 men and 80 women with the mean age of 43.4 ± 10.1 years (range, 16-60 years), were enrolled in the current study. 37 out of the 115 patients underwent PFDD, while the remaining 78 received PFDRT according to the surgical assessment. The operation time in PFDRT group (159.3 ± 40.0 min) was higher than that in PFDD group (134.1 ± 30.8 min) (P < 0.05). Besides, 20 cases in PFDRT group (20/78) developed postoperative dizziness and headache, and such incidence was higher than that in PFDD group (3/37) (P < 0.05). After 6 months of follow-up, a total of 69 patients (88.4%) in PFDRT group had alleviated symptoms, while 31 (83.8%) patients in PFDD group had improved symptoms. Altogether, the SM cavity was reduced in 54 patients (69.2%) in PFDRT group and 29 (78.4%) in PFDD group, respectively, after the operation. No statistical differences in symptom improvement and cavity reduction rate could be witnessed between the two groups.

Conclusion: Our study suggests that both PFDRT and PFDD can achieve comparable short-term clinical outcomes for adult CM-I patients. Surgical treatment is considered to be a reliable choice for the treatment of adult CM-I patients. Typically, PFDRT may lead to a higher risk of aseptic inflammatory complication. The precise surgical procedure should be selected based on detailed conditions of patients.