Figure 2.
Pathophysiological classification of PPI-refractory NERD. Based on the results obtained from intra-esophageal manometry and 24-h-long intra-esophageal pH/impedance monitoring, the subjects were classified into three groups according to the Rome III criteria: acid reflux-related mechanism, non-acid reflux-related mechanism, and functional heartburn. This figure is original from the present authors.