To assess prospectively the usefullness of hepatobiliary imaging in acute abdominal pain (72 hr or less), 36 patients were scintigraphed after intravenous injection of 5 mCi of Tc-99m p-isopropyl-iminodiacetic acid (PIPIDA). Before the procedure, the referring physician completed Part I of a questionnaire indicating his differential diagnosis, diagnostic confidence (expressed as a percentage), and therapeutic plan. Immediately after the test, the same physician, with knowledge of the results,

more »

... mpleted Part II of the questionnaire indicating again his differential diagnosis, diagnostic confidence, and therapeutic plan. The impact of the imaging on the physician's diagnositic confidence was expressed as a log-likelihood-ratio (LLR). The mean LLR for this series was 1.48 +/- 0.93, with 33 of 36 (92%) patients demonstrating a LLR greater than 0.0. In 26 of 33 patients, a LLR greater than 1.0 was achieved; and in 11 of 36 patients, a change in the physician's therapeutic plan occurred, reflecting the considerable impact of hepatobiliary imaging on the decision-making process.