肛瘘磁共振成像:探讨自制可调节肛肠水囊在肛瘘分级中的价值

目的:探讨普通MR成像中使用自制可调节肛肠水囊在肛瘘患者分级中的应用价值.方法:18例经手术证实的肛瘘患者于使用自制可调节肛肠水囊前、后均各行一次MRI检查.序列包括T_1 WI横断位和冠状位、T_2 W SPAIR横断位,冠状位及矢状位.放置水囊前后比较瘘管末端位置,并且对瘘管、内口、分支及脓腔进行计数,同时观察瘘管走行.所获结果被用于评估肛瘘MR诊断分级,并同时与手术结果相对照.结果:18名肛瘘患者MRI检查共发现瘘管31根、内口22个、分支19根以及脓腔10个.使用水囊前后MRI对瘘管末端位置的显示有显著不同(χ~2=5.56,P<0.05).使用水囊前,MR显示1例1级低位单纯线形括约肌内肛瘘,1例低位和2例高位2级括约肌内肛瘘伴脓肿或分支,1例3级高位经括约肌肛瘘,6例4级经括约肌肛瘘伴脓肿或分支,其中5例为高位,1例为低位,2例5级高位肛提肌上和经肛提肌肛瘘,另有5例无法确定;使用水囊后,2级高位括约肌内肛瘘伴脓肿或分支上升为3例,4级低位经括约肌肛瘘伴脓肿或分支上升至2例,高位上升至7例,另有1例无法确定,余小变.使用水囊前后,M RI对肛瘘分级与手术的相符率分别为72%(13例)和94%(17例).结论:通过使用自制町凋节肛肠水囊,普通M RI能够获得更多有关瘘管及其走行的信息,有助于肛瘘患者的分级.

MR Imaging of Perianal Fistulas: Value of Using an Innovative Self-adaptive Ano-rectal Water Plug for the Classification

Purpose: To investigate the value of using an innovative self-adaptive ano-rectal water plug for the classification of perianal fistula in conventional MRI studies. Methods: Eighteen perianal fistula patients underwent MR scans with a body coil before and after using an innovative self-adaptive ano- rectal water plug in order to dilate the anal canal and rectum. The sequences included T_1 WI in the axial and coronal planes and T_2W SPAIR in the axial, coronal, and sagittal planes. Whether the end locations of tracts could be distinguished above or below the ano-rectal ring were compared with and without the water plug. The number of fistulas, the internal openings, extensions and abscesses were counted. The routes of fistulas were observed. All MR findings were utilized to evaluate the classification of the fistulas and compared with the surgery results. Results: On MR imaging, there were 31 fistulas, 22 internal openings, 19 extensions and 10 abscesses observed. A Chi-square test revealed significant differences of the end locations of tracts on MR images before and after using water plug (χ~2 = 5.56, P < 0.05) . According to MR images, 1 grade one simple lincear intersphincteric low fistula, 3 grade two intersphincteric fistulas with intersphincteric abscess or secondary fistulous track (1 was low and 2 were high), 1 grade three trans-sphineteric high fistula, 6 grade four trans-sphincteric fistulas with abscess or secondary track within the ischioanal or ischiorectal fossa (1 was low and 5 were high), and 2 grade five supralevator and translevator diseases were classified without water plug. Five fistula patients were uncertain. With water plug, there were 3 high grade two fistula patients. Further 1 grade four low and 2 grade four high fistula patients were observed, and still 1 patient was uncertain. Before and after using the water plug, complete agreement between MRI and surgery for the classification occurred in 13 (72%) and 17 (94%). Conclusion: By using an innovative self-adaptive ano- rectal water plug, conventional MRI can obtain more information of the fistulas and their routes, and it is useful in the classification of the perianal fistula patients.