Domkundwar Shilpa V, Shinagare Atul B
Grant Medical College, Sir J. J. Group of Hospitals, Mumbai, India.
J Ultrasound Med. 2007 Jan;26(1):29-36. doi: 10.7863/jum.2007.26.1.29.
The purpose of this study was to evaluate the role of transcutaneous perianal ultrasonography in evaluation of fistulas in ano and to assess its possible role as a first-line investigation, for follow-up, and as a possible substitute for magnetic resonance imaging.
Transcutaneous perianal ultrasonography was performed in 30 patients with fistulas in ano with the use of a 3- to 6-MHz sector probe, a 7- to 11-MHz linear probe, and a 5- to 7-MHz endocavitary probe. Patients were followed clinically and at surgery to assess the accuracy of transcutaneous perianal ultrasonography.
A total of 43 fistulas, sinus tracts, or both were found in 26 patients. They appeared as hypoechoic tracts. Eleven of 30 patients had the presence of a collection or abscess, which appeared as hypoechoic areas. Twenty-four of 29 patients with positive findings underwent surgery. In these, 35 of 39 tracts were surgically confirmed (positive predictive value, 90%). The positive predictive value for demonstration of an internal opening was 85% (22/26) when compared with direct visualization or probing. Sensitivity for detection of tracts was 100%, and that for demonstration of an internal opening was 96% (26/27). The negative predictive value for sinus/fistulous tracts was nearly 100%. Transcutaneous perianal ultrasonography could not adequately evaluate suprasphincteric-type fistulas. However, it is a good, inexpensive modality in the evaluation of patients with fistulas in ano and also helps in follow-up of these patients. It can also be used to select patients who need magnetic resonance imaging.
Transcutaneous perianal ultrasonography has the potential to become the first investigation in patients with perianal fistulas and abscesses.
本研究旨在评估经皮肛周超声检查在肛管瘘评估中的作用，并评估其作为一线检查、随访以及磁共振成像可能替代方法的潜在作用。
对30例肛管瘘患者使用3至6兆赫扇形探头、7至11兆赫线性探头和5至7兆赫腔内探头进行经皮肛周超声检查。对患者进行临床和手术随访，以评估经皮肛周超声检查的准确性。
26例患者共发现43条瘘管、窦道或两者皆有。它们表现为低回声区。30例患者中有11例存在积液或脓肿，表现为低回声区。29例检查结果阳性的患者中有24例接受了手术。其中，39条瘘管中有35条经手术证实（阳性预测值为90%）。与直接观察或探查相比，内口显示的阳性预测值为85%（22/26）。瘘管检测的敏感性为100%，内口显示的敏感性为96%（26/27）。窦道/瘘管的阴性预测值接近100%。经皮肛周超声检查无法充分评估括约肌上型瘘管。然而，它是评估肛管瘘患者的一种良好且廉价的方法，也有助于对这些患者进行随访。它还可用于选择需要磁共振成像的患者。
经皮肛周超声检查有可能成为肛周瘘和脓肿患者的首选检查方法。
