Background: In this study, we quantify the work done by the esophagus to open the esophagogastric junction (EGJ) and create a passage for bolus flow into the stomach. Work done on the EGJ was computed using functional lumen imaging probe (FLIP) panometry. Methods: Eighty-five individuals underwent FLIP panometry with a 16 cm catheter during sedated endoscopy including asymptomatic controls (n=15), 45 achalasics (n=15 each, three subtypes), GERD (n=13), eosinophilic esophagitis (EoE; n=8) and systemic sclerosis (SSc; n=5). Luminal CSA and pressure were measured by the FLIP catheter positioned across the EGJ. Work done on the EGJ (EGJW) was computed (millijoules, mJ) at 40 mL distension. Additionally, a separate method was developed to estimate the "work required" to fully open the EGJ (EGJROW) when it did not open during the procedure. Results: EGJW for controls had a median (IQR) value of 75 (56-141) mJ. All achalasia subtypes showed low EGJW compared to controls (p<0.001). GERD and EoE subjects had EGJW 54.1 (6.9-96 .3) and 65.9 (10.8-102.3) mJ, similar to controls (p<0.08 and p<0.4, respectively). The scleroderma group showed low values of EGJW, 12 mJ (p<0.001). For achalasics, EGJROW was the greatest and had a value of 210.4 (115.2-375.4) mJ. Conclusions: Disease groups with minimal or absent EGJ opening showed low values of EGJW. For achalasics, EGJROW significantly exceeded EGJW values of all other groups highlighting its unique pathophysiology. Balancing the relationship between EGJW and EGJROW is potentially useful for calibrating achalasia treatments and evaluating treatment response.
Esophagogastric Junction Distensibility on Functional Lumen Imaging Probe Topography Predicts Treatment Response in Achalasia—Anatomy Matters!