多层螺旋CT联合瘘管造影对肛瘘的术前评价

目的探讨瘘管造影后多层螺旋CT(multi-slice computed tomography,MSCT)在肛瘘术前评价中的价值。方法术前对27例怀疑肛瘘的患者瘘管造影后行MSCT平扫及三维重建,其中13例行增强扫描,并与手术或随访结果对照。结果27例中手术证实肛瘘23例,4例临床随访为肛周感染破溃,MSCT诊断3例为单纯性肛瘘,20例为复杂性肛瘘,4例未发现肛瘘。MSCT正确分级:1级肛瘘3例,2级肛瘘18例,另2例3级肛瘘误诊为2级肛瘘。MSCT对内口及支管评价的敏感度、特异度、准确度、阳性预测值和阴性预测值分别为60.8%、85.7%、66.7%、93.3%、40.0%以及92%、100%、93.1%、100%和66.7%,对脓肿预测值则均为100%。MSCT三维重建能再现瘘管的形态和走行特点、瘘管与肛管内外括约肌和肛提肌的关系。结论MSCT联合瘘管造影是一种术前评价肛瘘的有效方法。

Preoperative assessment of multi-slice CT combined with fistulography for anal fistula

Objective To preoperatively assess the value of multi-slice spiral computed tomography(MSCT) combined with fistulography for the diagnosis of anal fistula.Methods Preoperative MSCT examination was performed in 27 patients with clinically suspected anal fistulas and results were compared with surgical and follow-up findings.Results A fistula was identified by a surgery in 23 cases. Three simple fistulas,and 20 complex fistulas were diagnosed by MSCT.Intraoperatively 3 patients of grade 1 and 18 of grade 2 were confirmed,and there were 2 cases of grade 3 fistula misdiagnosed as grade 2 fistulas.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of MSCT for internal openings were 60.8%,85.7%,66.7%,93.3%,40.0% respectively;and that for secondary tracts were 92.0%,100.0%,93.1%,100.0%,66.7% respectively.All indices for abcesses were 100.0%.The MSCT 3D reconstuction can well demonstrate the shape of fistula and its relationship with the sphincter complex and levator ani muscle.Conclusion MSCT combined with fistulography is very effective for the preoperative assessment of anal fistula.