Clinical symptoms include dysphagia, foul breath, regurgitation and/or aspiration. The condition is usually insidious, developing between age 30-50, and is likely due to a defect in esophageal innervation, with impairment or absence of ganglion cells in Auerbach's Plexus.
Radiographically, abnormal peristalsis (often completely absent) and abnormal LES opening are seen with barium swallows. Barium remains above the LES until pressure (hydrostatic or nonperistaltic contractions) wedges the LES open. When this occurs, the barium column appears as an elongated "V" or "bird beak" yet latter term is not specific for achalasia.
Upper endoscopy is necessary to rule out a benign or malignant stricture. Failure of LES relaxation is confirmed by esophageal manometry that also reveals complete absence of contractile activity, referred to as aperistalsis (“classic achalasia”) or persistent spastic contractions (“vigorous achalasia”).
Treatment options aim to relax the LES, and include medicines (smooth muscle relaxants), balloon dilation (70-80% success, often requires re-dilation, risk of perforation), or surgical myotomy of the LES (now often done laparascopically, and combined with antireflux surgery.)