Transperineal and transvaginal sonography of perianal inflammatory disease

OBJECTIVE. Perianal infection arises in small intersphincteric anal glands predominantly located at the dentate line. Documentation of fluid collectio ns and the relationship of inflammatory tracts to the sphincter mechanism i s important for surgical treatment. Transanal sonography for assessment of perianal inflammatory disease is limited because placement of the rigid pro be into the anal canal does not allow assessment of disease in the perineal region. The purpose of this study was to validate the use of transperineal sonography in men and both transvaginal and transperineal. sonography in w omen for evaluation of perianal. inflammatory disease. SUBJECTS AND METHODS. Fifty-four patients, 28 men and 26 women, were imaged with transperineal and a combination of transperineal and transvaginal son ography, respectively. All patients were examined in the supine lithotomy a nd left lateral position with a transvaginal 8- to 4-MHz probe or a linear 12- to 7-MHz transducer. AE fluid collections, sinus tracts, and fistulas w ere described by their location in relation to the sphincter mechanism and perineum. RESULTS. Forty-six of 54 patients had perianal fistulas or sinus tracts: 33 transphincteric, seven intersphincteric, and six extrasphincteric. Fifteen patients had an associated abscess. In the eight remaining patients, there were two anovaginal fistulas, one rectovaginal fistula, one prolapsed inte rnal hemorrhoid, two perianal complex masses, and two vascular perianal or perirectal inflammatory masses. Twenty-six patients underwent surgical proc edures involving the anorectal canal or perirectal region, and of these, pr eoperative sonographic findings were confirmed in 22 (85%) of 26 patients. Three patients refused surgery, and six are awaiting surgery at dris writin g. Fifteen patients were treated conservatively. CONCLUSION. Transperineal and transvaginal sonography are accurate, painles s, and cost-effective methods for documenting perianal fluid collections an d fistulas or sinus tracts or both.