An unnatural, narrow channel leading from some natural cavity – such as the duct of a gland, or the interior of the bowels – to the surface. Alternatively a ﬁstula may be a communication between two such cavities where none should exist – as, for example, a direct communication between the bladder and bowel.
Cause Fistulas may be congenital or develop as a result of injury or infection. A SALIVARY ﬁstula may develop between the salivary gland and the outside of the cheek because of a blockage in the duct from the gland to the mouth. A urinary ﬁstula may be one consequence of a fracture of the PELVIS which has damaged the URETHRA. Fistulas of the anus are one of the most common forms, usually the result of infection and ABSCESS formation.
Treatment As a rule, a ﬁstula is extremely diﬃcult to close, especially after it has persisted for some time. The treatment consists in an operation to restore the natural channel, be it salivary duct, or urethra, or bowel. This is eﬀected by appropriate means in each locality, and when it is attained the ﬁstula heals quickly under simple dressings.