Nuclear Medicine Technology and Other Health Applications Extension and Improvement Project Title: Diagnostic Techniques 16. Technical Progress in FY 1973: of Radiographic and Isotopic RX-01-03-(c) (Cont'd,.) I-123 was compared with Tc-99m for thyroid imaging; the definite superiority of I-123 was apparent. Labeled hippuran was also used but sufficient quantities are not now available for clinical use. A study of I-123 iodoquin for eye melanomas is in progress in collaboration with Dr. Samuel Packer of St, Albans Naval Hospital, the BNL’ Chemistry Department and Instrumentation Division, Evaluation of carbon-ll labeled dopamine for adrenal scanning has shown excellent concentration of the compound in the adrenal medulla as compared to other tissues at two hours. However, this is impractical because of the short half-life of C-ll. evaluated, Relative concentrations at earlier times are being ~ + Thallium-201 production methods are being worked out on the cyclotron for use prior to BLIP production of the isotope. Myocardial localization has-been determined in mice and rats. The ability to visualize infarcted areas in the myocardium is being evaluated in goats following surgical induction of infarcts by ligating coronary arteries, In the studies on transmission scanning, the Instrumentation Division has devised a useful clinical system for imaging iodine distribution in vivo, With a radiation dose of only a few mrad, it should be possible to image the iodine naturally found in the thyroid, Animal studies showed the distribution of Cholografin and Hypaque, iodinated contrast agents in the biliary system and urinary tract. Xenon also was used successfully as a positive pulmonary contrast agent in animal studies, Use in humans awaits . approval of the Institutional Review Committee of the Hospital of the Medical Research Center, A contract with NIH for production of Tc-97m as a radiographic source for mammography was approved and funded. The use of critical absorption edge filters to improve radiographic contrast, possibly resulting in reduced radiation exposure, is being evaluated. The simplified helium early closure test of pulmonary function using helium and a leak detector mass spectrograph was applied to a large number of normal individuals at all age levels and with varying smoking habits. The apparatus developed in collaboration with members of the BNL Department of Appl Science determines the time of small airway closure, the earliest indi on of chronic obstructive pulmonary disease, The results are being analy . (Atkins) The following report of progress during the past year is repeated in RX-01-03-(e). . (See Continuation Sheet) [119218 RX-60