Introduction
St Mark’s has pioneered investigation and treatment of haemorrhoids, anal fistula, anal fissure, incontinence and problems of bowel function since it was founded in 1835.
We have a centre that is unique and a world renowned team who are capable of translating new developments into patient care. Despite this, some people still suffer major problems from anorectal disease.
What is an anal fistula?

An anal fistula is a track between the skin on the outside of the buttock/anal area and the anal canal on the inside. There are many different types of fistulae from relatively simple to a complex branching network of tracks. Some fistulae may involve the muscles responsible for bowel control. Each fistula is individual. The diagram below shows some different types of fistula.
The anal fistula operation
Many different operations can be done for a fistula. You should discuss with your surgeon exactly what is planned for you. The aim is to cut out or lay open the infected track so as to promote healing from the base of the wound out to the surface, preventing unhealed pockets of infection from being left trapped inside. This healing can be a slow process, taking from a week or so up to several months. It is impossible to predict how long it will take in each individual case. Further inpatient treatment may be required. This could involve a subsequent visit to the operating theatre to examine the wound under anaesthetic. Sometimes a stitch (called a Seton suture) is inserted to avoid dividing the muscle. Your surgeon will explain this to you if it is needed in your case. To read in detail, please read our Information For Patients Document.
The Fistula Team
Mr Phil Tozer Consultant Colorectal Surgeon

Mr Phil Tozer was trained as a general and colorectal surgeon in London with a focus of both his clinical and academic training under Professor Robin Phillips at St Mark’s Hospital. His thesis in idiopathic and Crohn’s anal and rectovaginal fistula was the beginning of a passionate interest in advanced proctology and IBD. His clinical and academic work continue to focus on these areas of the Fistula Research at St Mark’s. He has published numerous papers in scientific journals on these topics and supervises research fellows in the FRU, continuing research on aetiology, investigation and novel treatments for fistula.