Clinical Observation Of Posterior Fossa Decompression Duroplasty Combined With Spinal-subarachnoid Shunt In The Treatment Of Chiari Malformation Type Ⅰ Complicated With Syringomyelia

Objective:The postoperative improvement of patients with Chiari malformation type Ⅰ(CMⅠ)associated with Syringomyelia(SM)was followed to discuss the effects of Posterior Fossa Decompression Duroplasty(PFDD)combined with Spinal Subarachnoid Shunt(SSS).Methods:From May 2020 to December 2022,a total of 14 patients with CMⅠ were admitted to the Spinal Surgery Department of the First Affiliated Hospital of Nanchang University.Following a rigorous screening process,8 patients met the inclusion and exclusion criteria and were subsequently included in the study.Magnetic Resonance Ⅰmaging(MRⅠ)was completed before surgery for all patients,suggesting different degrees of cerebellar subtonsillar hernia and syringomyelia.By Japanese Orthopedic Association score(JOA),Neck Disability Ⅰndex(NDⅠ)and Chicago Chiari Outcome Scale(CCOS)to assess postoperative clinical improvement.The location of the subtonsillar hernia(L value),maximum anterior and posterior diameter of syringomyelia(D value)and central sagittal area of syringomyelia(S value)were measured by MRⅠ to evaluate the postoperative imaging improvement of the patients.Overall efficacy evaluation criteria were formulated based on the above6 indicators to evaluate the clinical symptoms,signs and imaging improvement of the subjects.To explore and assess the overall effectiveness of PFDD+SSS in CMⅠ combined with SM patients.Results:The 8 patients were all female,with an average age of 46.63±9.27 years and an average course of disease of 40.13±46.79 months.The median follow-up time was 24 months,the longest follow-up time was 32 months,and the shortest follow-up time was 8 months.All patients were treated by the same team.All patients’ postoperative JOA,NDⅠ,CCOS,L,D and S values,as well as those from 3 months and the last follow-up,were significantly different from preoperative(p<0.05).The average recovery rate of cerebellar tonsillar hernia length in the last follow-up was 24.88%compared with the preoperative recovery rate,and the average anterior-posterior diameter and area of syringomyelia in the last follow-up were 51.88% and 66.25%respectively.According to the overall efficacy evaluation criteria,the curative effect of 6 patients was "improved" at the last follow-up,with an improvement rate of 75%.Conclusions:The findings of this study indicate that the PFDD combined with SSS is a secure and efficient surgical approach that can notably enhance the patients’ postoperative clinical symptoms and indications,successfully alleviating syringomyelia.Ⅰt is a viable option for patients with CMⅠ complicated with SM.