Preoperative physiological esophageal assessment for anti-reflux surgery: A guide for surgeons on high-resolution manometry and pH testing

Figure 7 Examples of achalasia diagnosed on high-resolution manometry. A: Type I achalasia with failure of lower esophageal sphincter relaxation and absence of peristalsis; B: Type II achalasia with panesophageal pressurization; C: Type III achalasia with abnormal peristalsis (spastic/premature contractions).