The field of radiology is continuously changing. The purpose of this study was to identify the effect of technologic advances on nuclear medicine during the past 15 y. Methods: The number of radiopharmaceutical doses dispensed at Mayo Clinic (Rochester, Minnesota) from 1990 through 2004 was tracked. The number of doses was equivalent to the number of scans performed. Results: Since 1990, the number of bone scans decreased by 38%. Brain scans using The field of radiology is continuously changing.Knowledge of these changes and why they occurred will allow us to predict future use trends in nuclear medicine. Physicians order specific tests on the basis of the patient's symptoms and probable diagnosis. As technology advances, new tests are compared with previously established methods to determine the best method of diagnosing certain diseases. If the new test is superior, it may replace the previously used examination method. The purpose of this study was to identify changes in nuclear medicine use at Mayo Clinic (Rochester, Minnesota) over the past 15 y and determine why those changes occurred.
MATERIALS AND METHODSThe number of radiopharmaceutical doses dispensed at Mayo Clinic Rochester from 1990 through 2004 was tracked using Nuclear Pharmacy Manager software (Bristol-Myers Squibb). This program tracks all doses dispensed from our laboratory, and the values correspond to the number of studies performed using a specific radiopharmaceutical agent. We determined the total number of scans performed each year and the number of scans performed using specific radiopharmaceuticals. Data for PET tumor imaging were based on the number of clinical scans performed each year, not the number of doses dispensed.We measured the number of bone scans that used 99m Tcmedronate and 99m Tc-oxidronate; brain scans that used 99m Tcexametazime and 99m Tc-bicisate; myocardial perfusion scans that used 201 Tl-thallous chloride and 99m Tc-sestamibi; lung ventilation and perfusion scans that used 133 Xe gas and 99m Tc-macroaggregated albumin; kidney scans that used 99m Tc-mertiatide, 99m Tcsuccimer (dimercaptosuccinic acid [DMSA]), 99m Tc-pentetate (diethylenetriamine penta-acetic acid [DTPA]), and 131 I-hippuran; and tumor scans that used 111 In-pentetreotide and 18 F-FDG. These radiopharmaceuticals were chosen because of the prevalence of their use and because we suspected that their use patterns changed over time. Only radiopharmaceutical doses dispensed for clinical patients were included in our study (radiopharmaceuticals used in research studies were excluded). As new radiopharmaceuticals were developed, use of other pharmaceuticals typically diminished; older radiopharmaceuticals often were replaced completely by the new agents for imaging of a specific organ system. For example, 99m Tc-DTPA was replaced by 99m Tc-mercaptoacetyltriglycine in renal scintigraphy. When more than one type of radiopharmaceutical was used for a particular imaging modality, values were compared and summed to determine the total number of scans of that orga...