What is Sphincterotomy?

Sphincterotomy is a surgical procedure to cut or stretch sphincter. Sphincter is the circular muscles around the anus that control bowel movement (BM).

Sphincterotomy is a treatment for patients that suffers from anal fissures, piles or sometimes described as passing of glass. The purpose of sphincterotomy is to loosen the sphincter muscles and facilitate healing.



The procedure or operation is not to be confused with fistulotomy. Fistulotomy is a surgical operation on fistula, an abnormal growth in various tracts in the body organ. However, it is common to have both sphincterotomy and fistulotomy performed in the same operation.

There are 2 types of sphincterotomy :

  1. Lateral Internal Sphincterotomy (LIS) – This the only type of sphincterotomy used to treat anal fissure.
  2. Endoscopy Sphincterotomy (EST) – This is a type of surgery using endoscope to remove gallstones from bile (not a treatment for anal fissure)

Sphincterotomy is not the only treatment available for anal fissures. Below are some other common treatments, usually for less serious cases of anal fissure :

  • High fibre diet
  • Stool softneners
  • Botox

Botox (botulinum toxin) treatment is also known as chemical sphincterotomy. It is performed by injecting Botox into the internal sphincter. It involves no surgical procedure.

In many anal fissure cases, sphincterotomy usually is the final solution suggested when all other treatments failed.