- dysmotility disorder
- five times less common than achalasia
- strong repetitive non-propulsive contractions interspersed with normal peristaltic waves
- these contractions may obliterate esophageal lumen
- sometimes presents with chest pain
barium swallow
- corkscrew or curling esophagus due to strong non-propulsive contractions
- marked esophageal wall thickening
- due to high pressure, occasionally diverticula may be seen