耻骨直肠肌综合征的影像学诊断及临床意义

Image analysis of puborectalis syndrome and its clinical significance

目的探讨排粪造影、CT和磁共振成像(MRI)在耻骨直肠肌综合征(PRS)的诊断价值及局限性。方法收集83例PRS患者的临床资料,包括排粪造影、盆底静息和最大用力排便时的CT、MRI扫描结果。分别测量肛直角(ARA)及其压迹长度、深度和耻骨直肠肌的厚度；并与56位正常人的排粪造影、CT和MRI检查结果进行对照分析。结果正常人ARA力排相较静息相明显增大。83例PRS患者中62例ARA力排相较静息相明显减小,且均伴有耻骨直肠肌(PRM)压迹,PRM压迹长度为(3．52±0．65)cm,深度为(1．68±0．49)cm；另外21例患者的静息、力排时ARA均无变化,钡剂不排或少排且均出现“搁架征”。CT、MRI断面图像上,PRS患者PRM较正常人厚度明显增加(P＜0．01)；且还能清晰显示出盆底肌群、筋膜及其周围间隙。结论排粪造影显示的PRM功能性异常是诊断PRS较可靠的方法。CT、MRI能直接清楚地显示PRM位置、形态大小及与邻近结构的关系,将三者有机结合对早期、全面诊断PRS及指导治疗具有重要意义。

Objective To discuss the clinical value and application range of defecography, CT and MRI in diagnosis of puborectalis syndrome （PRS）. Methods The clinical data of 83 PRS patients, including defecography, CT and MRI scanning in pelvic floor resting and defecation at maximum exertion, measurement of anorectal angle（ARA）, length and depth of ARA impression and the thickness of the puborectalis muscle, were collected, and compared with those of 56 normal persons. Results For normal persons, ARA at maximum exertion was more significantly increased than that at resting. In 62 cases with PRS, ARA at maximum exertion was more obviously reduced than that at resting and associated with puborectalis muscle（PRM） impression. In the other 21 cases, ARA showed no changes at either maximum exertion or resting, a little or no excretion of barium appeared and ＂shelving syndrome＂ was showed. The cross-sectional images of CT and MRI showed that the puborectalis of PRS patients were thicker than that of normal persons （P 〈 0.01）. PRS patients also showed clear pelvic floor muscle, fasciae and peripheral crevice. Conclusions Defecogrphy, manifested the abnormal function of the puborectalis muscles, is a reliable method for diagnosis of PRS. In the meantime, CT and MRI are able to clearly display the position, growth status and size of the puborectalis muscles as well as its relation with adjacent structures, which provide further understandings on anatomical changes, abnormal adjacent structure and other functional diseases of pelvic floor in PRS patients. Therefore, an appropriate combination of the 3 methods play an important role in the early diagnosis of PRS and guidance for surgical treatment.