Chiari畸形Ⅰ型与寰枢椎不稳关系的研究进展

Research progress of Chiari malformation type I and atlantoaxial instability

Chiari畸形(Chiari malformation,CM)是一组累及颅颈交界区的先天性小脑扁桃体下疝畸形。其中Chiari畸形Ⅰ型(Chiari malformation typeⅠ,CMⅠ)在临床上最为常见,但其发病机制仍不清楚,其外科治疗标准也未达成共识。目前最广泛被接受的是后颅窝不相容学说,因此后颅窝减压术(posterior fossa decompression,PFD)及硬膜扩张成形术(posterior fossa decompression with duraplasty,PFDD)为外科治疗的金标准,并在金标准的基础上有所改进。但部分患者后颅窝容积与健康人无差别,且约30%的CMⅠ患者行PFD术后效果欠佳,因此该术式不能治疗全部的CMⅠ患者。近年来随着影像学发展、诊断技术进步以及对Chiari畸形认识的深入,有研究证实CMⅠ可能与寰枢椎不稳有关,并提出CMⅠ为寰枢椎不稳的继发因素,寰枢椎融合术成为外科治疗标准在学术界引起较大的争议。有研究显示寰枢椎融合术治疗CMⅠ患者术后临床症状缓解率达96.9%;也有研究显示寰枢椎融合术治疗CMⅠ患者术后70%的患者神经功能改善,但总体术后效果欠佳。CMⅠ与多种疾病相关,临床表现复杂,因此应结合患者临床表现及辅助检查结果进行个体化管理与治疗。

Chiari malformation(CM)is a group of congenital cerebellar tonsillar hernia malformations involving the craniocervical junction.Chiari malformation type I(CMI)is the most common in clinic,however its pathogenesis is still unclear,and there is no consensus on the surgical treatment standard of CMI.At present,the most widely accepted is the theory of posterior fossa incompatibility,so doctors at home and abroad use posterior fossa decompression(PFD)and posterior fossa compression with duraplasty(PFDD)as the gold standard for surgical treatment,and have their own experience and technical improvement.However,the volume of the posterior cranial fossa in some patients is no different from that in healthy people,and about 30%of the patients with CMI have poor results after posterior cranial fossa decompression.As a result,this operation cannot treat all patients with CMI.In recent years,with the development of imaging,the progress of diagnostic technology and the deepening of understanding of CM,some studies have shown that CMI may be related to atlantoaxial instability,and proposed that CMI is the secondary factor of atlantoaxial instability,and atlantoaxial fusion is the standard of surgical treatment,which has caused great controversy in academic circles.Different clinical research results of scholars support or oppose this theory:some studies have shown that the clinical symptom relief rate of patients with CMI treated with atlantoaxial fusion is 96.9%;another study showed that 70%of patients with CMI underwent atlantoaxial fusion had improved neurological function,but the overall postoperative effect was not satisfactory.In short,CMI is related to many diseases and its clinical manifestations are complex.Therefore,individualized management and treatment should be carried out in combination with the clinical manifestations and auxiliary examination results of patients.