How is Fissure diagnosed?

Diagnosis can be made by inspection. Closer inspection will frequently reveal a tag or sentinel pile. After gentle separation of the skin of the anal verge, the ulcer usually posterior can be seen. Frequently the fibers of the internal anal sphincter muscle can be seen at the base of this punched-out ulcer. A well-lubricated finger with lidocaine ointment and a small caliber anoscope will help delineate the extent of the lesion. A colonoscope or sigmoidoscope exam might be useful to rule out abscesses, colitis, and other causes of rectal bleeding.
A fissure should be distinguished from an ulcer caused by Crohn’s disease, leukemia, or malignant tumors, because it is not shaggy, large or indolent. Fissures are seldom multiple. A biopsy can help to determine the diagnosis