Lateral internal sphincterotomy

Lateral internal sphincterotomy (LIS) is a surgical procedure used primarily to treat chronic anal fissure. The procedure involves the surgical division of the internal anal sphincter, which reduces sphincter tone and subsequently rectal pressure. This reduction in pressure promotes healing of the anal fissure and reduces pain and discomfort for the patient.

Indications

Lateral internal sphincterotomy is indicated for patients with chronic anal fissure who have not responded to conservative treatments such as dietary fiber supplementation, stool softeners, and topical nitroglycerin or calcium channel blockers. It may also be indicated in patients with recurrent anal fissures.

Procedure

The procedure is typically performed under general anesthesia or spinal anesthesia. The surgeon makes a small incision in the skin over the internal anal sphincter and then divides the sphincter muscle. This reduces the resting pressure in the anal canal, which promotes healing of the fissure and reduces symptoms.

Complications

As with any surgical procedure, lateral internal sphincterotomy carries potential risks and complications. These may include bleeding, infection, anal incontinence, and recurrence of the anal fissure. However, the procedure has a high success rate and complications are relatively rare.

Prognosis

The prognosis following lateral internal sphincterotomy is generally good. Most patients experience significant relief from pain and other symptoms. The fissure typically heals within a few weeks of the procedure, and the risk of recurrence is low.

See also

• Anal fissure
• Sphincterotomy
• General anesthesia
• Spinal anesthesia