Figure 2. Non-occlusive contractions detected with FLIP.
Patients were considered to have occlusive contractions if any observed contraction on FLIP topography achieved a luminal diameter ≤ 6 mm and non-occlusive if the minimal diameter reached was > 6mm. Frequencies varied between normal controls and achalasia (p = 0.005) and among achalasia subtypes (p = 0.004: type I vs type II, p = 0.057; type I vs type III, p = 0.001; type II vs type III, p = 0.022).