LAUSR

A 49-year-old male patient presented with pus discharge from multiple external openings in the perineum for the last 1 year. The external openings were present in the left and right perianal region, at the base of the scrotum and on the penile shaft (dorsal aspect, at the base) (Fig. 1). The patient was a known diabetic and there was no history of Crohn’s disease, tuberculosis, any sexual transmitted disease, urinary tract infection, hematuria or pyuria, any injury to the perineal region or any previous anorectal or urological surgery. General examination was unremarkable. On local examination, there was induration and tenderness in the posterior midline of the anal canal. MRI revealed a horseshoe fistula with anal opening at the posterior midline. The horseshoe tract traversed the ischioanal fossa on both sides, opening in the perianal skin at 3 and 9 o’clock on either side. The right-sided fistula tract in the ischioanal fossa extended anteriorly with a skin opening at the base of scrotum. The main tract continued further anteriorly infiltrating into the lateral aspect of the right corpus cavernosum (Figs. 2 and 3). The tract with its infiltration of the corpus cavernosum traversed about 6.7 cm in the penile shaft (Fig. 3, Sagittal section) and then opened into the skin at the dorsal aspect of the base of the penis. The corpus spongiosum and urethra were spared by the fistula. There was no supralevator extension. A diagnosis of high transsphincteric horseshoe fistula with penile involvement was made. The patient underwent a sphincter-sparing procedure – Transanal opening of the intersphincteric space (TROPIS). In this procedure, the external anal sphincter (EAS) is not cut or damaged at all. The internal opening and the portion of fistula in the intersphincteric space is laid open into the anal canal. This is done through the