Long-standing progressive dysphagia, regurgitation of undigested food, nocturnal choking (aspiration), and a dilated esophagus with smooth, gradual distal narrowing (bird's beak / rat tail) on barium swallow are classic for achalasia. An epiphrenic diverticulum shows a pouch, and diffuse esophageal spasm shows a corkscrew pattern without proximal dilatation.