Objective To systematically evaluate posterior fossa decompression with duraplasty (PFDD) and posterior fossa decompression without duraplasty (PFD) for Chiari malformation type I (CM-I). Methods A meta-analysis was performed according to the guideline of the MOOSE statement. Relevant literature and references were electronically searched in CENTRAL, Science Citation Index Expanded, MEDLINE (Ovid), PubMed, CBM, CNKI and WanFang Data from 1993 to September 2011. Two reviewers independently identified literature according to inclusion and exclusion criteria. The included studies were evaluated using the Newcastle-Ottawa Scale. Original data were extracted and analyzed using RevMan 5.1 software. Besides, the level of evidence was assessed using the GRADE system. Results Ten studies involving 829 patients were included. The results of meta-analyses showed that: a) compared with patients undergoing PFD, patients undergoing PFDD had a significantly lower reoperation rate (RR=0.41, 95%CI 0.23 to 0.74, P=0.003), and a higher rate of syringomyelia decrease (RR=1.27, 95%CI 1.03 to 1.56, P=0.02). But there was no significant difference in clinical improvement (RR=1.11, 95%CI 0.95 to 1.28, P=0.18). b) compared with PFD, patients undergoing PFDD had a higher rate of cerebrospinal fluid–related complications (RR=6.3, 95%CI 2.71 to 14.67, Plt;0.000 1). There were no significant differences in the complication of occipital neuralgia and wound infection (Pgt;0.05). Based on GRADE system, the evidence was at Level C and we made a weak recommendation. Conclusion Posterior fossa decompression with duraplasty is associated with a lower risk of reoperation, a better effect of syringomyelia decrease and a greater risk for cerebrospinal fluid–related complications, compared with PFD. Due to the influencing factors of lower-quality included studies, a prudent choice is suggested, and also more high-quality, large-sample studies are need.
目的：总结54例Chiari畸形合并脊髓空洞症的显微外科手术治疗经验。方法：本组对1998年9月至2005年9月共收治的54例Chiari畸形合并脊髓空洞症患者采用后路手术入路，对颅底凹陷症采用后路减压，显微镜下行小脑扁桃体软膜下部分切除，正中孔开放手术治疗。结果：54例患者术中观察发现延髓和上颈髓明显受压和不同程度同小脑扁桃体粘连，正中孔引流不畅；随访1月～7年，术后42例症状显著改善，12例明显改善；影像学复查提示脊髓空洞明显缩小。结论：显微外科手术治疗Chiari畸形合并脊髓空洞症疗效确切可靠。
ObjectiveTo evaluate the effectiveness of the posterior atlantoaxial lateral mass screw fixation and suboccipital decompression in the treatment of Arnold-Chiari malformation associated with atlantoaxial joint dislocation. MethodsBetween September 2012 and November 2015, 17 cases of Arnold-Chiari malformation associated with atlantoaxial dislocation were treated by the posterior atlantoaxial lateral mass screw fixation and suboccipital decompression and expansion to repair the dura mater and bone graft fusion. There were 10 males and 7 females, aged 35-65 years (mean, 51.4 years). The disease duration was 14 months to 15 years with an average of 7.4 years. According to Arnold-Chiari malformation classification, 13 cases were rated as type I, 3 cases as type II, and 1 case as type III-IV. Cervical nerve root stimulation and compression symptoms were observed in 12 cases, occipital foramen syndrome in 11 cases, cerebellar compression symptoms in 6 cases, and syringomyelia in 10 cases. ResultsPrimary healing of incision was obtained in the other patients except 1 patient who had postoperative cerebrospinal fluid leakage after removal of drainage tube at 3 days after operation, which was cured after 7 days. All patients were followed up 6 months to 2 years, with an average of 18.4 months. The neurological dysfunction was improved in different degrees after operation. The Japanese Orthopedic Association (JOA) score was significantly increased to 16.12±1.11 at 6 months from preoperative 11.76±2.01 (t=13.596, P=0.000); compression of spinal cord and medulla was improved. X-ray examination showed bone graft fusion at 6 months after operation. In 10 patients with spinal cord cavity, MRI showed empty disappearance in 3 cases, empty cavity lessening in 6 cases, and no obvious change in 1 case at 6 months. ConclusionAtlantoaxial lateral mass screw fixation and suboccipital decompression and expansion to repair the dura mater can obtain good effectiveness in the treatment of Arnold Chiari malformation associated with atlantoaxial transarticular dislocation.