目的评价磁共振扩散加权成像 序列(DWI)结合常规序列对复杂性肛瘘显 示的准确性，探讨DWI在复杂性肛瘘中的 应用价值。方法 30例经手术证实的复杂 性肛瘘患者术前均行MRI检查，扫描序列 包括常规序列横轴位T1WI、T2WI、T2WI 脂肪抑制，冠状位、矢状位T2WI脂肪抑 制及DWI，以手术结果为标准，分别观察 并比较评估常规扫描序列和常规扫描序 列+DWI对肛瘘瘘管、内口及脓肿的显示 情况。结果 30例肛瘘患者，MR常规扫描 序列诊断内口灵敏度为81.4%(38/43)， 阳性预测值为89.7%(35/39)；瘘 管灵敏度为90.2%(37/41)，阳性 预测值86.0%(37/43)；脓肿灵敏 度91.6%(11/12)，阳性预测值 100%(11/11)；常规序列+DWI诊 断内口灵敏度95.3%(41/43)，阳 性预测值95.3%(41/43)，瘘管灵 敏度92.7%(38/41)，阳性预测 值97.4%(38/39)，脓肿灵敏度 100%(12/12)，阳性预测值100%(12/12), 两种诊断方法比较，常规序列+DWI对肛瘘 的诊断效果要优于常规序列，其中对内口 的显示灵敏度有统计学差异(P<0.05)。 结论 磁共振常规序列+DWI显示肛瘘内 口、瘘管及脓肿具有较高的临床应用价 值，可以作为外科手术前的常规检查。

Objective To evaluate the accuracy of diffusion weighted imaging (DWI) combined with generic sequence in complex anal fistula and to discuss the application value of DWI in complex anal fistula. Methods 30 cases of patients who were confirmed with complex anal fistula were given MRI before operation. Scan sequences included axial T1WI, T2WI and fat sequence T2WI, and coronal and sagittal fat sequence T2WI and DWI. With surgical results as the standard, conventional sequences and conventional sequences + DWI were compared for anal fistula, internal opening and abscess. Results For 30 cases of patients with anal fistula, sensitivity and positive predict value of MR conventional sequences were 81.4%(38/43) and 89.7%(35/39) respectively for internal opening; 90.2%(37/41) and 86.0%(37/43) for anal fistula; 91.6%(11/12) and 100%(11/11) for abscess. Sensitivity and positive predict value of MR conventional sequences + DWI were 95.3%(41/43) and 95.3%(41/43) for internal opening; 92.7%(38/41) and 97.4% (38/39) for anal fistula; 100%(12/12) and 100%(12/12) for abscess. In comparison of two kinds of diagnostic methods, conventional sequences + DWI had better diagnostic results on anal fistula than conventional sequences, and the sensitivity for internal opening was of statistical difference (P<0.05). Conclusions MRI + DWI shows higher clinical application value for internal opening and canal of anal fistula and abscess, which can be used as a conventional preoperative examination.