https://mahnoorsiddiqa.blogspot.com/2024/05/how-to-prepare-for-fistula-surgery.html
A fistula is an abnormal connection between an organ, vessel, or intestine and another organ, vessel or intestine, or the skin. Fistulas can be thought of as tubes connecting internal tubular structures, such as arteries, veins, or intestine, to one another or to the skin.