摘要： 目的  介绍于神经导航引导下单纯内镜下经鼻腔行齿状突切除术治疗颅底凹陷畸形的手术方式，阐明与传统经口腔入路相比较的优势。方法  自2009 年9 月-2010 年2 月共对2 例先天性颅底凹陷畸形患者施行神经导航内镜下经鼻腔入路齿状突切除手术，其中例2 同期接受经后路枕颈固定融合术。采用日本骨科协会（JOA）评分（17 分法）系统评价手术前后患者脊髓神经功能变化。结果  患者均于麻醉清醒后早期拔除气管插管，次日即可经口进食。术后头部CT 重建和MRI 扫描显示，硬脊膜压迫完全解除，减压效果满意。例2 患者术后发生脑脊液漏，经腰椎穿刺引流10 d 治愈；术后无一例发生伤口感染。随访24 个月以上，神经功能恢复良好，JOA 评分分别从术前的12 和8 分恢复至最近一次随访的17 和15 分。结论  于神经导航内镜下经鼻腔行齿状突切除术可以成功解除颅底凹陷畸形对延髓颈髓的压迫。相对于传统的经口腔入路，其微创优势包括改善术中视野、减轻舌体水肿、减少牙齿损伤、避免长时间插管或气管切开、无需鼻胃管营养，以及不影响术后发声功能等。

关键词: 颅底, 先天畸形, 颅骨切开术, 神经内窥镜检查

Abstract: Objective To introduce the surgical techniques of image-guided endoscopic transnasal odontoidectomy to treat basilar invagination with congenital osseous malformations and describe several advantages compared to the traditional transoral procedure. Methods From September 2009 to February 2010, two cases with basilar invagination, of which the etiology was congenital osseous malformations, underwent endoscopic transnasal odontoidectomy. Case 2 also received occipitocervical fixation and bone fusion during the same surgical episode to ensure stability. The clinical symptoms of the two cases were evaluated by using the Japanese Orthopaedic Association (JOA) score for the evaluation of cervical myelopathy. Results Both patients were extubated after recovery from anesthesia and allowed oral food intake the next day. Cerebrospinal fluid rhinorrhea was found in the second case and cured by continuous lumber drainage of cerebrospinal fluid. No infection was noted. The average follow?up time was more than 24 months. Remarkable neurological recovery was observed at postoperation in both patients. The JOA scores elevated from preoperative 12 and 8 to postoperative 17 and 15. Conclusion The endoscopic transnasal odontoidectomy is a more minimally invasive approach for anterior decompression of cervicomedullary with basilar invagination. The advantages over the standard transoral odontoidectomy include visualization improvement, elimination of risk of tongue swelling and teeth damaging, alleviation of prolonged intubation, reduction of need for enteral tube feeding, and less risk of affecting phonation.

Key words: Skullbase, Congenital abnormalities, Craniotomy, Neuroendoscopy