Fistulas
A fistula is an abnormal connection or tunnel between two areas. In the anorectal region, the most common cause of the fistula is from a blocked crypt or gland at the anorectal junction. The gland then becomes inflamed, and in an effort to expel its infected contents, expresses itself, usually as an abscess. As with thrombosed hemorrhoids, the collection of fluid within a fixed area, and the associated inflammation, becomes exquisitely tender. You may have systemic signs of illness, including fever. Once the abscess either drains spontaneously or is incised (cut open) and allowed to drain, the pain diminishes. However, a connection between the offending crypt and the outer opening, seen usually in the perianal region, may remain. Occasionally, the outer opening remains in the rectum, and the abscess and the fistula can only be identified by an examination, often under anesthesia. Rarely, the origin of the infection stems from the abdomen or pelvis, as in diverticulitis.

Acutely, management of the abscess includes drainage. However, about half of these abscesses remain as fistulas. These fistulas may cross the anal sphincter muscles to their originating gland. The most effective treatment for managing these fistulas is fistulotomy, which connects the outer and inner openings and facilitates drainage of the inner opening. Unfortunately, division of the sphincter muscle or muscles may impair continence, and thus, other alternatives exist for management of this difficult problem.

A flap of the lining of the rectum may be created to cover the internal opening. This is called a mucosal advancement flap. Some series report as high as 85% chance of cure, however, in most other series, the chance for cure is lower. Another possibility is that of injecting fibrin glue into the tract. The chance for cure is lower still, around 50 - 60%. Finally, a piece of suture or rubber band can be used to either hold the tract open, thus allowing for drainage, or can be gradually tightened, as in orthodontic braces, to gradually cut through the muscle in a graded fashion, where scar formation would be facilitated over time.

Your surgeon will discuss these options, and perhaps others, with you. Fistula management is complex and requires knowledge of the special anatomy in this area and disease states in order to drain the infection, cure the fistula, while maintaining continence.