Myotomy

Myotomy is a surgical procedure that involves cutting muscle fibers to relieve abnormal constriction or spasm. It is used to treat conditions in which muscle tone at an orifice or along a muscular segment impedes passage or function. Common indications include esophageal achalasia, infantile hypertrophic pyloric stenosis, and certain forms of strabismus. The goal is to reduce resting muscle tone or excursion at the affected location.

In esophageal achalasia, myotomy is performed to disrupt the lower esophageal sphincter muscle. The principal approaches are Heller myotomy (cardiomyotomy), usually performed laparoscopically and often accompanied by a partial fundoplication to reduce reflux. An endoscopic alternative is per-oral endoscopic myotomy (POEM), which creates a tunnel in the esophageal wall and divides circular muscle fibers. Pyloromyotomy (Ramstedt pyloromyotomy) is traditionally used in infantile hypertrophic pyloric stenosis, where the pyloric muscle is split to widen the passage from stomach to duodenum; the mucosa remains intact.

In ophthalmology, myotomy can refer to cutting or weakening an extraocular muscle to correct strabismus, sometimes used in combination with other procedures such as recession or resection of adjacent muscles.

Relief of obstruction or dysmotility is common, with success rates varying by indication and technique. Risks include perforation, bleeding, infection, reflux after esophageal myotomy, residual dysphagia, and, in ocular cases, overcorrection or diplopia. Recovery and need for postoperative therapy depend on the approach and condition treated.