Fistula in the bile ducts, visualized with contrast agent.
A fistula (Latin: fistula) or pipe ulcer is a non-natural channel (congenital, artificial or swollen) between two body cavities or between a body cavity and the skin. A fistula may also be an opening between a gland and the skin.
A fistula usually occurs after an inflammation in the body cavity or in the gland. If the inflammation has expanded to the skin, it may break up spontaneously or break through. If the inflammation itself is healed, a fistula can still survive, which may occasionally come out of dirt or moisture. However, the fistula often grows again when the inflammation is cured.
Sometimes an artificial connection is made, for example between an artery and a vein to facilitate dialysis in the kidney dialysis. Such a connection is also called shunt. Examples
Not all fistula disappear. If bleeding is bad, it may be that a fistula remains. This can often be resolved in an operative way.
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