强直性骶髂关节炎的CT诊断及分级

目的 分析63例强直性骶髂关节炎(骶强柱)患者骶嚣关节CT图像，归纳其CT特征并进行CT分期。方法 回顾性连续收集本院门诊及住院临床诊断为骶强柱患者63例，所有患者均行骶髂关节CT扫描，部分患者有骶嚣关节X线平片。结果 63例患者分为四期：Ⅰ期30例，Ⅱ期26例，Ⅲ期14例，Ⅳ期3例。CT表现Ⅰ期：关节面皮质白线中断、或白线增宽、模糊、密度减低，关节面下骨质呈小囊状改变，病变多局限于髂骨侧，关节间隙正常。Ⅱ期：关节面呈“毛刷状”或“缺刻”改变，骨质增生增厚更加明显，关节间隙无明显改变。Ⅲ期：关节面明显骨质破坏，呈“锯齿状”骨质缺损，关节问隙不规则狭窄。Ⅳ期：关节间隙消失，两侧关节面融合，关节间隙留有一条高密度硬化痕迹。结论 强直性骶嚣关节炎，CT能显示其影像学特征，作出正确的诊断及分级。

CT diagnosis and stage of sacroiliac joint with ankylosing spondylitis

Objective To retrospectively analyze the appearances of sacroiliac joint(SIJ) with ankylosing spondylities(AS) and to evaluate the value of CT in the diagnosis and stage.Methods CT findings of 63 cases with AS proved clinically were analyzed and graded.Results There were 30 cases in stage one,26 ones in stage two,14 ones in stage three,3 ones in stage four.In stage one,symmetric or asymmetric involvment of SIJ were found.The manifestations were vague articular face,interrupted joint cortex and subcortical microcysts.In stage two,brush-like joint face,subcortical cyctic destruction were remarkable,and no remarkable narrowed joint space.In stage three,serrated like joint face,and irregularly narrowed joint space were found.In stage 4,calcification of ligament,bony ankylosis of the joint with obliteration of joint space and osteoporosis or osteosclerosis were the findings.Conclusion CT scan could clearly describe subtle changes of the struction of SIJ with AS.It is beneficial for AS to make correct diagnosis and stage.