Update in achalasia: what the surgeon needs to know.

Achalasia is a motility disorder encountered by surgeons during the investigation and treatment of dysphagia. Recent advances in manometry technology, a widely accepted new classification system and a new treatment rapidly gaining international acceptance, have changed the working knowledge required to successfully manage patients with achalasia. We review the Chicago classification subtypes of achalasia with type II achalasia being a predictor of success and type III achalasia a predictor of treatment failure. We review per-oral endoscopic myotomy as an emerging treatment option and its potential for improving the treatment of type III achalasia.