先天性无肛畸形儿MR成像及其与排便功能关系研究

目的评估先天性肛门直肠畸形儿（anorectal malformations，ARM）尾端发育情况及横纹肌复合体（sphincter muscle complex，SMC）发育状态与排便功能的关系。方法39例ARM，男28例，女11例，应用不同序列体部相控阵列线圈或头部线圈MRI显示ARM直肠闭锁水平、骶尾椎、骶髓、泌尿生殖系的发育情况，并对SMC从多个层面进行定量分析，评估其发育状态与临床评分和肛门功能客观检查的关系。结果39例患儿中，MRI T1WI、T2WI扫描判断畸形水平的正确诊断率为100％，T2WI扫描瘘管检出率为96．9％。骶尾椎和骶髓的异常占41．0％，泌尿生殖系统畸形占20．5％。当耻骨直肠肌宽度的相对值PRWR〈0．18，外括约肌宽度的相对值EASWR〈0．15时，71．4％的ARM术后出现肛门失禁。当PRWR〉0．18，EASWR〉0．15时，91．3％的ARM术后排便功能好。结论MR检查能清楚地显示ARM类型、闭锁水平、SMC发育状态、脊柱脊髓及泌尿生殖系统存在的伴发畸形，从MR影像中找到了评价SMC的定量指标。

MR imaging of anorectal malformations and the studies on the relationship of the developmental state of the sphincter muscle complex and continent function

Objective To evaluate the spectrum of developmental anomalies in the caudal region of patients with anorectal malformations(ARM) and the imaging studies on the developmental state of the sphincter muscle complex(SMC) and continent function.Methods 39 patients,including 28 boys and 11 girls,with ARM were investigated with magnetic resonance imaging(MRI).The imaging studies examined the level and type of ARM,the associated anomalies of spinal cord,spine,and urogenital system and the relationship of the developmental state and continent function.Results Of 39 patients,MRI accuracy for the level of ARM was 100%(39/39) and for the fistulae(verified surgically) was(96.9%)(31/32).The associated anomalies of spinal cord and spine were found in(41.0%) of patients.The urogenital system anomalies were found in(20.5%) of patients.(71.4%) of patients with PRWR<(0.18) and(EASWR)<(0.15) developed fecal incontinence post-operatively.(91.3%) of the patients with PRWR>(0.18) and EASWR>(0.15) were continent post-operatively.Conclusions MRI demonstrates certain features of anorectal anomalies which correlate well with the prognosis of the fecal continence.