Farhaan Rowshan Mir, Presenter: Nothing to Disclose

Kastytis Charles Karvelis MD, Abstract Co-Author: Nothing to Disclose

A recent consensus recommendation has served to standardize previously variable methods of performing radionuclide gastric emptying scintigraphy (GES) examinations. This approach requires imaging for 4 hours following standard meal ingestion. The extended protocol has been shown to be superior to shorter 1 and 2 hour studies. Some authors have suggested that 3 hour gastric emptying studies may have equivalent accuracy to 4 hour examinations. If 3 hour imaging could be shown to have similar accuracy, this would result in increased patient throughput and improved utilization of imaging resources.

Standard GES was performed on 30 sequential patients using the recommended consensus methodology. Images were obtained at 0, 1, 2, 3, and 4 hours. Percent emptying at 3 and 4 hours were compared for each individual patient. The four hour percent emptying was used as the gold standard. More than 30% remaining activity at 3 hours and >10% activity at 4 hours were considered abnormal.

28 of 30 patients (93%) had concordant results (normal vs abnormal) at 3 and 4 hours. Nineteen patients had normal gastric emptying values at 3 and 4 hours. Nine patients whose GES was classified as abnormal at 3 hours subsequently also had abnormal gastric emptying at 4 hours. Of the remaining 2 patients, one had normal emptying at 3 hours (<30%normal) but was abnormal at 4 hours. The remaining patient had abnormal emptying at 3 hours, but normal emptying at 4 hours (<10%). Using the 4 hour exam as the gold standard, the 3 hour exam has a sensitivity of 90%, specificity of 95%, positive predictive value of 90%, and negative predictive value of 95%.

In this limited number of patients, utilizing 3 hour GES was largely equivalent to the consensus recommendation 4 hr GES. It would result in increased convenience for the patients as well as improved utilization of imaging resources and personnel without sacrificing diagnostic accuracy. Previous studies have shown similar efficacy using a 3 hour imaging maximum, and this study also supports that conclusion.

An abbreviated gastric emptying protocol may provide more efficient patient throughput, as well as more optimal utilization of imaging resources.

Mir, F, Karvelis, K, Faster Throughput with Equivalent Accuracy? Evaluation of Abbreviated Gastric Emptying Scintigraphy (GES).  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9003145.html