Internal Orifice Alloy Closure: A New Procedure for Treatment of Perianal Fistulizing Crohn's Disease

Abstract

BACKGROUND The high recurrence rate of perianal fistula Crohn's disease (PFCD) increases the need to protect the anal sphincter during each surgical treatment of fistulas. We aimed to evaluate the safety and efficacy of internal orifice alloy closure in patients with PFCD. MATERIAL AND METHODS Fifteen patients with PFCD were enrolled in the study between July 6, 2021, and April 27, 2023. All patients underwent preoperative colonoscopy and anal magnetic resonance examination for diagnosis and evaluation. Internal orifice alloy closure (IOAC) was performed only when Crohn's disease was in remission. The external sphincter had not been severed. Perianal magnetic resonance imaging examination was used for postoperative evaluation after 6 months. Fistula cure rate, length of stay, perianal pain, and Wexner incontinence score were retrospectively compared between 15 patients treated with IOAC and 40 patients treated with other surgical methods. RESULTS Fifteen patients (male/female: 9/6, age: 23.6±14.3 years) with PFCD were included (follow-up: 24 months). In total, 20.0% (3) had multiple tracts, and 13.3% (2) had a high anal fistula. Among them, 10 patients received biologics for induction for mucosal healing before surgery. The fistula healed completely in 80.0% (12/15) and did not heal in 20.0% (3/15). Three patients who did not heal underwent fistulotomy and eventually recovered. IOAC is not superior in terms of fistula healing rates, length of stay, and anal pain, but its Wexner incontinence scores are significantly lower than with other surgical methods. CONCLUSIONS IOAC is a novel sphincter-saving surgery that is effective and safe for the treatment of PFCD.

Figure 1

The general process of the patient from presentation to surgery and postoperative testing. Because patients have different conditions before surgery and need to meet the standards for endoscopic mucosal healing, the time of use of biological agents and the waiting time before surgery are different.

Figure 2

(A–D) MRI images of a perianal fistula in a young male patient with PFCD before and 6 months after IOAC. Note that the inflammatory component (T2 hyperintensity and collections) markedly improved and the fistula track disappeared. The oblique coronal plane and oblique transverse plane are parallel and perpendicular to the longitudinal axis of the anal canal, respectively. The orange arrows indicate changes in the site of the lesion.

Figure 3

Schematic diagram of the anal fistula clip. The anal fistula clip has a three-lobe design, and the alloy is soft at 0°C. At 36°C, the alloy has a strong centripetal force and can clamp the central tissue.

Figure 4

IOAC surgery was performed on a young male PFCD patient with repeated perianal surgery. (A) Confirmation of the internal orifice of the fistula. (B) Clean the epithelium lining the fistula. (C) The mucosa 1 cm around the internal orifice was removed. (D) The muscular layer was closed by the anal fistula clip (blue arrowheads).

Figure 5

The comparison of quality of life of patients between the 2 groups. Questionnaire data from 15 patients in study groups showed scores of 8–67, while the control group had scores of 19–80 (possible range from 0 to 108). The scores were approximately normally distributed, and the average score of the study group and control group was 31.1 and 51.8, and the standard deviation was 18.3 and 14.8, respectively. *** P<0.001