Contractile and pressure profiles of achalasia subtypes

The spectrum of achalasia across the achalasia subtypes. Initially, patients may present with an esophagogastric junction (EGJ) outflow obstruction pattern (panel A) in which there is impaired lower esophageal sphincter (LES) relaxation with evidence of propagating contractions. This may represent the point where the esophageal body is progressing to aperistalsis and there is variable loss of the excitatory (dark circles) and inhibitory (light circles) influence. As loss of the inhibitory neurons continues to progress, the manometric pattern may progress to a type II pattern (panel B) associated with impaired LES relaxation and panesophageal pressurization, similar to a water-filled balloon being squeezed. There is typically a normal lumen or mild to moderate dilatation with non-occluding contractions as evidenced on the esophagram. Type I achalasia (panel C) is the classic presentation of achalasia, in which there is complete loss of contractile activity in the body of the esophagus; this is typically a later phase of disease progression where there is evidence of moderate to severe esophageal dilatation. Type III achalasia (panel D) is associated with premature simultaneous contractions that compartmentalize the bolus before it can empty the esophagus, as evidenced by the corkscrew appearance on esophagram. This may represent a distinct entity that does not fall into the typical presentation of progressive neuron loss and is similar to what is seen with opioid-related effects in the esophagus. However, there are instances where a type III pattern can be an intermediate step between EGJ outflow obstruction and Type II achalasia. Corresponding barium esophagrams are also shown for each subtype.