Gastroesophageal scintigraphy: is it a sensitive screening test for gastroesophageal reflux disease?

Dynamic radionuclide imaging potentially offers a convenient, noninvasive technique for detecting gastroesophageal (GE) reflux disease. Initial studies suggested a high degree of sensitivity, although subsequent reports have been less encouraging. We sought to clarify this controversy by assessing the sensitivity of GE scintigraphy in 15 patients with severe esophagitis at endoscopy and 15 health volunteers. After acid loading, scintigraphy was performed in the basal state and after maneuvers (Valsalva, abdominal compression) which provoke GE reflux. Computer analysis permitted calculation of a reflux index for each maneuver. An index greater than 4% was considered a positive test. We found that the mean reflux index for the patients was significantly greater (p less than 0.01) than the healthy volunteers; 4.55 +/- 1.75% versus 0.42 +/- 0.11%, means +/- S.E.M. Only 30% of the patients had a reflux greater than 4%. Using data from our healthy volunteers, we redefined an abnormal reflux index as greater than 1.7%, but that only improved the test sensitivity to 60% and the specificity to 100%. Scintigraphy for reflux is primarily limited by the short duration of imaging. We cannot recommend GE scintigraphy as a useful screening test for reflux.