FIGURE 1.

Esophageal body compliance and distensibility plateau (DP) measurement on FLIP panometry. FLIP panometry output from two patients (a, b) is displayed as length (16 cm) × time × color-coded diameter FLIP topography (top panels) with corresponding intra-balloon pressure (bottom panels). The smart box (black boxes) was positioned at an 8 cm segment of the esophageal body at two FLIP fill volumes, with care to avoid areas affected by dry catheter artifact (indicated by dashed arrows). Esophageal body volume was calculated within the area of the smart box, as was the associated median pressure value to facilitate calculation of esophageal body compliance as ΔVolume (V)/ΔPressure (P), that is (V2–V1)/(P2–P1). The distensibility plateau (DP) is indicated by “*.” Patient (A) Had normal compliance of 0.28 ml/mmHg ((30–25 ml)/(33–15 mmHg)) and normal DP (20 mm). Patient (B) Had reduced compliance of compliance 0.08 ml/mmHg ((15–12 ml)/(72–35 mmHg)) and reduced DP (12 mm). The figure used with permission from the Esophageal Center of Northwestern