Fig. 4From: Pseudoachalasia presenting 20 years after Nissen fundoplication: a case reportAn algorithm that can be utilized to differentiate between achalasia and pseudoachalasia. Abbreviations: UGI, upper gastrointestinal series; EGD, esophagogastroduodenoscopy; HRM, high-resolution manometry; EUS, esophageal ultrasound; LES, lower esophageal sphincter; IRP, integrated relaxation pressure; EGJ, esophagogastric junctionBack to article page