Sphincter damage during fistulotomy for perianal fistulae and its relationship with faecal incontinence

Abstract

Background The length of sphincter which can be divided during fistulotomy for perianal fistula is unclear. The aim was to quantify sphincter damage during fistulotomy and determine the relationship between such damage with symptoms and severity of faecal incontinence and long-term quality of life (QOL). Methods A prospective cohort study was performed over a 2-year period. Patients with intersphincteric and mid to low transsphincteric perianal fistulas without risk factors for faecal incontinence were scheduled for fistulotomy. All patients underwent 3D endoanal ultrasound (3D-EAUS) pre-operatively and 8 weeks postoperatively. Measurements were taken of pre- and postoperative anal sphincter involvement and division. Anal continence was assessed using the Jorge-Wexner scale and QOL scores pre, 6 and 12 months postoperatively. Results Forty-nine patients were selected. A strong correlation between pre- and postoperative measurements was found p < 0.001. A median length of 41% of the external anal sphincter and 32% of the internal anal sphincter was divided during fistulotomy. Significant differences in mild symptoms of anal continence were found with increasing length of external anal sphincter division. But there was no significant deterioration in continence, soiling, or quality of life scores at the 1-year follow-up. Division of over two-thirds of the external anal sphincter was associated with the highest incontinence rates. Conclusions 3D-EAUS is a valuable tool for quantifying the extent of sphincter involvement pre- and postoperatively. Post-fistulotomy faecal incontinence is mild and increases with increasing length of sphincter division but does not affect long-term quality of life.

The management of complex fistula in ano by transanal opening of the intersphincteric space (TROPIS): short-term results

“…Leaving the wound open in TROPIS allows healing of the wound by secondary intention and also aids in wound cleaning and curettage if pus drainage occurs during follow-up. Fistulotomy procedures also lay open the tract, which helps in drainage, but at the cost of postoperative incontinence in up to 24.2% to 62.8% of patients, depending upon the level of division of the external sphincter [12] as the external anal sphincter is not spared. In TROPIS, however, the external sphincter is spared, thus preserving continence.…”

Subcutaneous incision of the fistula tract and internal sphincterotomy (SIFT‐IS): a novel surgical procedure for transsphincteric anal fistula

“…Fistulotomy is the most reliable procedure for treating transsphincteric fistula in terms of healing rate, but postoperative incontinence occurs in up to 54% of cases [3,4]. The risk of postoperative incontinence depends on the amount of sphincter muscle involved in the fistula [4,18,19]; nevertheless, incontinence, including mild continence disorders, was observed in 24% even in…”

“…patients with a low fistula (less than one-third of the external sphincter division) [19]. It is necessary to consider a less invasive procedure for sphincter muscles in the treatment of transsphincteric anal fistula.…”

“…We speculate that the transformation of a perianal abscess to an anal fistula is contingent on Comparing existing procedures, we believe that SIFT-IS has beneficial clinical characteristics owing to the dissection in the subepithelial layer. Fistulotomy is the most prevalent procedure for transsphincteric fistulas, but there are risks associated with impaired anal continence owing to the division of the internal sphincter [3,4,18,19] SIFT-IS may overcome the postoperative incontinence associated with fistulotomy because the SIFT-IS approach is less invasive with regard to the internal sphincter.…”

The use of ultrasound in colonic and perianal diseases

“…A recent systematic review comparing the two primary imaging modalities (pelvic MRI and endoanal ultrasound [EAUS]) found the superiority of pelvic MRI over EAUS in most articles [ 16 ▪ ]. Nevertheless, EAUS can identify intersphincteric and transsphincteric fistulas, and internal fistula opening with high sensitivity and specificity, and results can be further improved with implementation of 3D-technique and hydrogen peroxide enhancement [ 17 , 18 ]. The latter may not be without risks as a case of hydrogen peroxide-induced proctitis after EAUS has recently been reported [ 19 ▪ ].…”