磁共振T1增强扫描对复杂性肛瘘诊断及分型的价值

目的：探讨磁共振T1增强扫描对复杂性肛瘘的诊断价值。方法：选取2015年2月至2018年1月温州医科大学附属第三医院和平阳县人民医院经手术证实的复杂性肛瘘患者43例，全部行T1加权成像（T1WI）、T2加权成像压脂（T2WI FS）和T1加权成像压脂（T1WI FS）增强序列扫描，与手术结果进行对照，比较3种序列对肛瘘内口、主管、支管的显示情况。结果：43例患者中，手术共发现内口67个，主瘘管63个，支管47个。T1WI发现内口10个（占14.93%）、主瘘管34个（占53.97%），支管10个（占21.28%）。T2WI FS发现内口52个（占77.61%）、主瘘管55个（占87.30%）、支管40个（占85.11%）。T1WI FS增强共发现内口61个（占91.04%）、主瘘管60个（占95.24%）、支管42个（占89.36%）。TIWI FS增强较T2WI FS显示内口的准确性高（P＜0.05），在显示主瘘管、支管的准确性方面两序列差异无统计学意义（P＞0.05）。T1WI FS增强显示内口、主瘘管、支管的准确性均较T1WI高，差异具有统计学意义（P＜0.05）。T1WI FS增强在Parks分型上与手术结果一致性高（Kappa=0.926），明显高于T2WI FS与T1WI序列（Kappa=0.786，Kappa=0.467）。结论：T1WI FS增强扫描序列可作为肛瘘MR检查常规T1、T2序列的重要补充，尤其是术前对内口的定位及分型评估中具有重要的指导价值。

The value of contrast-enhanced magnetic resonance T1-weighted imaging in the diagnosis and classification of complex anal fistula

Objective: To explore the diagnostic value of contrast-enhanced magnetic resonance T1-weighted imaging in complex anal fistula. Methods: A total of 43 patients with complex anal fistula which confirmed by surgery from the Third Affiliated Hospital of Wenzhou Medical University and the Pingyang People’s Hospital from February 2015 to January 2018 were included in the study. They were underwent T1-weighted imaging (T1WI), T2-weighted imaging with fat saturation (T2WI FS) and T1-weighted imaging with fat saturation (T1WI FS) contrast-enhanced sequences. The display of the three sequences on internal fistula, main canal and branch tube of anal fistula were compared with surgical findings. Results: Among the 43 patients, 67 internal openings, 63 fistulas and 47 fistula branches were found in surgeries. There were 10 internal openings (14.93%), 34 fistulas (53.97%) and 10 fistula branches (21.28%) found by T1WI. There were 52 internal openings (77.61%), 55 fistulas (87.30%) and 40 fistula branches (85.11%) found by T2WI FS. There were 61 internal openings (91.04%), 60 fistulas (95.24%) and 42 fistula branches (89.36%) found by T1WI FS contrast-enhanced scan. Compared with T2WI FS, TIWI FS contrast-enhanced scan had a higher accuracy in showing the internal openings (P<0.05), and there was no statistical difference between the accuracy of showing the fistula and the fistula branch (P>0.05). The accuracy of T1WI FS contrast-enhanced scan was higher than that of T1WI (P<0.05), and the difference was statistically significant. T1WI FS contrast-enhanced scan was highly consistent with surgical results in Parks classification (Kappa=0.926), which was obviously higher than T2WI FS and T1WI sequences (Kappa=0.786, Kappa=0.467). Conclusion: T1WI FS contrast-enhanced sequence can be an important supplement to conventional T2WI FS and T1WI sequences of anal fistula MR examination, especially in the preoperative localization of the internal openings and the classification assessment of complex anal fistula.