A novel continuous breath test versus scintigraphy for gastric emptying rate measurement

BACKGROUND: Gastric scintigraphy (GS) is considered the gold standard for gastric emptying rate (GER) measurement; however, it requires expensive equipment and special licensing for radioactive substances. AIM: To compare a new nonradioactive, real-time, continuous breath test (CBT) method with GS for the GER measurement. METHODS: Simultaneous GER analysis by both GS and CBT was carried out on 8 dyspeptic patients and 6 healthy controls. After a 14 hour fast, participants ate a standard meal of 250 Kcal double labeled with 1 mCi of Tc-99m and 100 μg of C-13 labeled octanoic acid. The participants underwent simultaneous GS for 120 minutes on single-detector γ camera and CBT carried out by attaching the nasal cannula of the system (Oridion, BreathID, Israel), which automatically and continuously collected and analyzed breath samples with real time display. A linear fit model was used to calculate gastric empting half-time. A half-time of more than 100 minutes for GS and 80 minutes for CBT were considered pathologic. The GS and CBT were compared by κ test of agreement in normal/abnormal results. RESULTS: Good correlation was found for GER measurements between GS and the CBT methods with a linear correlation coefficient of R=0.74. The κ test indicated excellent agreement with value of 0.86 for the qualitative determination of pathologic and normal results. CONCLUSIONS: The novel CBT provides reliable and reasonably accurate data for on-line GER estimate, in a simple manner suitable for medical clinics or bedside setting, without the use of radioactive substances.