Imaging Classification of Perianal Fistula Using the Ultrasound

Abstract

Introduction: Perianal fistula is defined as a tract lined by granulation tissue which may have external opening, internal opening or both external and internal openings. AIM: The study aimed to classify and assess the whole course of perianal fistula using the combined ultrasound transperineal, endoanal and endovaginal approaches. Material and Methods: Referred 480 patients were clinically diagnosed as a perianal infection (fistulas or abscesses) All were subjected to transrectal ultrasound (TRUS), transperineal and additionally if females transvaginal ultrasound. results: 30 cases detected with anal abscesses, among them 10 cases diagnosed as perianal abscesses, 5 cases with inter sphincteric plane abscesses, 11 cases with ischio anal fossa abscesses, 3 cases with horse shoe abscesses and 1 case with pelvi-rectal abscess. 450 cases detected with perianal fistulas were evaluated for the whole course of the fistula tract by combining transperineal, Transrectal and in females, Transvaginal ultrasound and could be classed according to the etiology, sphincteric course, extrasphincteric course, internal opening varieties, external opening varieties and the expected post-operative risks. Conclusion: The combined ultrasound technique using the endoanal or transvaginal and transperineal ultrasound approaches can be applied to fully evaluate the whole course of perianal fistula and it can contribute to minimize the incidence of postoperative recurrence and postoperative fecal incontinence.