MRI增强扫描在肛周脓肿术前诊断中的价值

目的探讨MRI不同方位及序列成像,尤其是冠状位及轴位T1WI压脂增强序列在肛周脓肿的术前诊断中的价值。方法经手术证实的30例脓肿患者全部进行增强MRI扫描。以手术结果为对照标准,统计分析MRI扫描三种序列组合对各种类型肛周脓肿及内口的检出率,并与直肠指诊进行对照分析。结果 30例患者手术证实52个脓肿,30个内口。直肠指诊肛周脓肿43个,检出率为82.69%,其中括约肌间脓肿15个,坐骨肛管间隙脓肿23个,肛提肌上方脓肿5个,正确的内口22个,检出率为73.33%。MRI轴位联合冠状位T1WI压脂增强序列检出肛周脓肿52个,检出率最高为100%,其中括约肌间脓肿18个,坐骨肛管间隙脓肿23个,肛提肌上方脓肿11个,正确的内口29个,检出率为96.67%。两组比较,对于肛提肌上方脓肿和内口的检出有统计学意义(P值分别为0.017和0.030)。结论肛周脓肿术前MRI增强扫描,能发现更多的肛提肌上方脓肿及明确的内口,为外科手术方式的选择提供更可信的影像资料。

To evaluate the preoperative diagnostic value of enhanced magnetic resonance imaging in perianal ;abscess

Objective To assess the contribution of various magnetic resonance imaging sequences, especially the axial, coronal and enhanced MRI sequences in preoperative diagnostic value of perianal obsess. Methods 30 patients with perianal abscesses confirmed by surgery were studied retrospectively. All the patients underwent enhanced MR imaging. By set surgical results as standard, the detection rates of types of perianal abscesses and internal openings among 3 MRI sequence combinations were statistically analyzed, together with Digital rectal examination. Results 52 perianal abscesses and 30 internal openings were found in 30 patients by surgery. They found 43 perianal abscesses with digital rectal examination. The detection rate was 82.69%, sphincter space in 15 cases,sciatic anal space abscess in 23 cases above levator ani in 5 cases and correct internal opening in 22 cases The detection rate was 73.33%. The combination of transverse and coronary enhanced T1WI-FS that found 52 perianal abscesses had a highest detection rate of perianal abscesses, 100%, sphincter space in 18 cases,sciatic anal space abscess in 23 cases above levator ani in 11 cases and correct internal opening in 29 cases, The detection rate was 96.67%, there were statistically difference in above levator ani and internal opening（P=0.017, P=0.030）. Conclusion The preoperative diagnosis of enhanced magnetic resonance imaging in perianal abscess, which could find more perianal abscess;and internal openings to choose the appropriate surgical approach.