The Ultrasound of Perianal External Opening

Background: An abscess, fistula tract, fistula with abscess formation and sinus tracts can lead to perianal external opening. The commonest cause which comes to the mind of the clinicians when they observe perianal external opening(s) is the presence of perianal sepsis. Methodology: 472 cases showing perianal external opening(s) were examined with transperineal, endorectal and if females with further transvaginal ultrasound. Results: The incidence of anal abscess was 3.4%, of perianal fistula was 93.4%, pilonidal sinus tract extending to the perianal spaces was 1.5%, the incidence of hiradenitis Suppurativa was 0.85%, the incidence of infected epidermal inclusion cyst was 0.21% and Bartholin abscess was 0.64% among our study group. Conclusion: Ultrasonography with its transperineal, endorectal and transvaginal approaches can be very helpful to the clinicians in the assessment of different etiologies that lead to the formation of perianal external opening to optimize the management