Fistulas

In anatomy, a fistula (: fistulas or fistulae ; from Latin fistula, "tube, pipe") is an abnormal connection (i.e. tube) joining two hollow spaces (technically, two epithelialized surfaces), such as blood vessels, intestines, or other hollow organs to each other, often resulting in an abnormal flow of fluid from one space to the other.

anus disease characterized by an abnormal connection between the epithelialised surface of the anal canal and the perianal skin

abnormal, epithelial-lined connection between an artery and vein that is present at the time of birth

fistula or abnormal connection between the rectum and the vagina

abnormal passage between the bladder and the vagina

between the bladder and the bowel