Department of Radiology, Innsbruck Medical University, Anichstrasse 35, 6020, Innsbruck, Austria,
Tech Coloproctol. 2014 Feb;18(2):165-71. doi: 10.1007/s10151-013-1031-x. Epub 2013 May 17.
Successful anal fistula care in complex cases can be assisted by specialized imaging which accurately defines the site of the internal fistula opening and the fistula type. There are currently limited data concerning the clinical indications for and accuracy of transperineal ultrasound (TP-US) in acute perianal sepsis. The aims of this study were to compare the anatomical interpretation of TP-US images with magnetic resonance imaging (MRI) and surgical findings in an unselected patient cohort presenting with acute perianal sepsis.
Sixty-seven consecutive patients with acute anorectal sepsis referred from the surgical department were examined using TP-US and Gadolinium-enhanced MRI with both examiners blinded to the surgical results. Fistulae were categorized by the Parks' classification of fistula type.
Thirty-six abscesses were detected by MRI, 38 by TP-US and 30 by surgical examination. Operatively discordant cases showed only ischiorectal panniculitis. TP-US was more accurate in the diagnosis of superficial sepsis and MRI in the diagnosis of deep-seated perirectal infection. TP-US and MRI show concordance with operative findings in fistula diagnosis with a tendency for TP-US to overdiagnose trans-sphincteric fistulae and MRI to over diagnose extra-sphincteric fistulae. Comparison of TP-US with MRI showed good agreement for perianal abscess diagnosis (τ = 0.82) and for fistula diagnosis (τ = 0.68). For fistulae, TP-US showed moderate agreement with surgery (τ = 0.43) with only fair agreement between MRI and surgery (τ = 0.29).
Transperineal ultrasound complements other imaging modalities in the anatomical diagnosis of acute perianal abscesses and fistulae. It has specific advantages over other techniques and is accurate in the detection of superficially located perirectal sepsis showing concordance with MRI and surgical findings.
在复杂情况下，专门的影像学可以准确地确定内部瘘口的位置和瘘管类型，从而有助于成功治疗肛门瘘。目前关于经会阴超声（TP-US）在急性肛周脓肿中的临床适应证和准确性的数据有限。本研究的目的是比较经会阴超声与磁共振成像（MRI）在未经选择的急性肛周脓肿患者中的解剖学解释与手术结果。
从外科部门转诊的 67 例急性肛门直肠脓肿患者接受了 TP-US 和钆增强 MRI 检查，两名检查者均对手术结果不知情。瘘管按 Parks 分类法分类。
MRI 检测到 36 个脓肿，TP-US 检测到 38 个，手术检测到 30 个。手术不一致的病例仅显示坐骨直肠间隙炎。TP-US 对浅表性感染的诊断更准确，MRI 对深部直肠周围感染的诊断更准确。TP-US 和 MRI 在瘘管诊断方面与手术结果一致，TP-US 倾向于过度诊断经括约肌瘘，MRI 倾向于过度诊断括约肌外瘘。TP-US 与 MRI 比较显示，肛周脓肿诊断具有良好的一致性（τ=0.82），瘘管诊断具有较好的一致性（τ=0.68）。TP-US 与手术比较，瘘管诊断具有中度一致性（τ=0.43），而 MRI 与手术的一致性仅为一般（τ=0.29）。
经会阴超声在急性肛周脓肿和瘘管的解剖学诊断中补充了其他影像学方法。它具有比其他技术更具体的优势，并且能够准确检测浅表性直肠周围感染，与 MRI 和手术结果一致。
