Esophageal potential difference measurements in esophageal disease

To determine if esophageal transmural electrical potential difference measurements are of use for evaluating esophageal disease, we recorded potential difference in 129 patients with one or more of the following: heartburn, dysphagia, and chest pain. All potential difference studies were performed at the time of esophageal manometry using a Ringer-perfused catheter technique which yields accurate and reproducible results in healthy subjects. In 103 of the 129 patients, esophageal potential difference measurements could be correlated with findings at manometry, endoscopy, and biopsy. The remaining 26 patients had primary esophageal motor disease and were not biopsied. The results of this investigation showed: (a) that 94% of patients with gross endoscopic lesions have an abnormal esophageal potential difference, (b) that an abnormal esophageal potential difference (found in only 1 of 24 patients with normal mucosa) is highly specific for the presence of esophageal mucosal disease, (c) that the type of potential difference abnormality may suggest the nature of the mucosal abnormality, for example high potential difference with Barrett's esophagus and low potential difference with esophagitis or invasive carcinoma, and (d) that while an abnormal esophageal potential difference is highly sensitive for detecting gross esophagitis (38 of 40 patients), it is less sensitive for diagnosing microscopic esophagitis (8 of 16 patients). Based on these findings we conclude that the measurement of esophageal potential difference at the time of manometry can provide additional valuable information about the state of the esophageal mucosa.