INTRARECTAL ULTRASOUND IN THE EVALUATION OF PERIRECTAL ABSCESSES

Experience with intrarectal ultrasonography (IRUS) is limited for the evaluation of perianal sepsis. The purpose of this article is to repor t our experience with IRUS in evaluating 24 cases of suspected periana l abscess and fistula. IRUS was performed intraoperatively using a Bru el & Kjaer (Model #1846; Naerum, Denmark) endoanal ultrasound scanner with a 7-MHz transducer. After completion of the IRUS, careful anorect al examination and appropriate surgical therapy were performed. At sur gery, 19/24 patients were found to have perirectal abscesses. with all 19 cases correctly identified preoperatively by IRUS. In 12 cases (63 percent), IRUS correctly defined the relationship between the abscess es and sphincters by Parks' classification. At surgery, internal openi ngs of fistulous tracts were found in 14/19 cases, but IRUS identified only 4/14 (28 percent). In 6/24 cases, IRUS and clinical evaluation d id not demonstrate a perirectal abscess. The role of IRUS in the evalu ation of perirectal abscess is evolving. Certainly, uncomplicated absc esses can be managed without ultrasonography. However, IRUS can be an adjunct to careful evaluation of complex perianal suppurative disease.