Reflux scintigraphy is often used to establish the diagnosis of gastroesophageal reflux disease (GERD). However, the efficacy of this modality is still debated. Therefore, Shim et al conducted a study to evaluate the role of reflux scintigraphy in the diagnosis of GERD by comparing it to 24-hr combined pH-impedance study.

Adult patients presenting for investigation of reflux symptoms were included in the study prospectively. Study participants were subjected to high resolution esophageal manometry and those having notable esophageal motor disorders were excluded. Eligible patients were subjected to reflux scintigraphy after insertion of the pH-impedance catheter.

In all, 30 patients were included in the study. Taking total acid exposure time (AET) of >4.2% as the reference for abnormal acid reflux, reflux scintigraphy was found to have a sensitivity of 62.5% and specificity of 68.2%, in identifying acid reflux. On comparing with AET >6%, reflux scintigraphy had a sensitivity of 66.7% and specificity of 62.5%, with a positive and negative predictive value of 30.8% and 88.2%, respectively.

Investigators noted no association between reflux scintigraphy outcomes and total AET, total (acid or non-acid) reflux events, proximal AET or the number of proximal reflux episodes on 24 h pH-impedance study.

To conclude, reflux scintigraphy seems to have a limited role in diagnosing GERD when compared with 24-hr combined pH-impedance monitoring.

Source: Shim LSE, Ngu MC, Yau Y, Russo R. Reflux scintigraphy in gastro-esophageal reflux disease: a comparison study with 24 hour pH-impedance monitoring. Scand J Gastroenterol. 2022 Jan 21;1-5.