Full Text Available D03466 Drug Chlormerodrin Hg 203 (USAN); Neohydrin-203 (TN) C5H11ClHgN2O2 369.0238 367.196 D03466.gif Diagno...stic aid [renal function determination]; Radioactive agent CAS: 2042-50-4 PubChem:
Orbital abnormalities can be evaluated by dynamic scintigraphy (radionuclide angiography) and static scintigraphy (radionuclide ''scanning''). The use of en face positioning improves the visualization of orbital details. Lesions can be detected and localized most accurately if multiple tracers are used for these studies. Abnormalities can be characterized by the recognition of various angiographic flow patterns, of distinct static distribution patterns, and of differences in the accumulation of multiple radiopharmaceuticals. The results of scintigraphic examination using technetium 99m sodium pertechnetate, mercury 197 chlormerodrin, and gallium 67 citrate in a series of 57 patients are reported. (U.S.)
Aquino, H.C.; Preston, D.F.; Luke, R.G.
Acute renal failure is a common complication of kidney transplantation. The major causes are acute tubular necrosis (ATN), arterial or venous thrombosis, rejection, ureteral obstruction, and extravasation. Each situation requires a different treatment and demands prompt diagnosis to prevent loss of the graft and patient morbidity or mortality. The clinical problem is further complicated by the possible coincidence of more than one of these pathologies, in particular the development of graft rejection superimposed on ATN in the post-transplant period. The diagnostic studies used in this differential diagnosis may include retrograde ureteral catheterization, renal arteriography, open or closed renal biopsy, isotope studies with /sup 133/xenon, /sup 131/I-hippuran, /sup 203/Hg-chlormerodrin, and more recently /sup 99m/pertechnetate. Only the latter methods with hippuran, chlormerodrin, and pertechnetate avoid direct manipulation of the graft or its artery or ureter with the inherent risks of such procedures. We present results of serial studies of sodium /sup 99m/pertechnetate photoscanning(Tc scan) in 38 renal homografts. In some studies computer determined graphs of renal radioactivity versus time (Tc renogram) were obtained.
Sterility testing of radiopharmaceuticals prepared at BARC were carried out using the radiometric technique (Radiometric detection of the metabolic product 14Co2). Batches of different radiopharmaceuticals were tested for pyrogen using the limulus lysate method and the results were compared with the rabbit method. The results of sterility test on 202 batches of 19 different radiopharmaceuticals show that the radiometric method can be used for sterility testing of radiopharmaceuticals labelled with 35S, 51Cr, 57Co, 59Fe, 82Br, 86Rb, sup(99m)Tc, sup(113m)In, 125I and 169Yb. The radiometric test proves to be more rapid than the conventional one for the sterility testing of such radiopharmaceuticals. Detection time is between 6-21 hours. In the case of 131I-labelled radiopharmaceuticals and in the case of chlormerodrin-Hg-203, it was found an interference due to volatile species (sup(131m)Xe in the case of 131I and some volatile mercury form in the case of chlormerodrin). In these cases it would be possible to carry out the radiometric sterility test after separation of the microorganisms from the radioactive material (by filtration). The limulus lysate method can be employed for control of various pyrogen-prone raw materials and radiopharmaceuticals. Such method is the only method at present available for detecting the low level pyrogen contamination in intrathecal injections. The limulus test is more rapid than the rabbit test
The need for a simple clinical test for singling out patients suffering from arterial hypertension due to renovascular causes has long been recognized. Over the past year, the authors have been using a linear scintillation scanner with ten detectors in parallel for delineating lesions within the kidney and estimating the rate of renal accumulation of 203Hg-labelled chlormerodrin. With this apparatus one can obtain very satisfactory renal images within two or three minutes after intravenous administration of 100 - 250 mCi of a radioactive drug. Scintigraphic images of both kidneys were obtained at 5, 10, 20, 30, 40, 50 and 60 min after administration of the radioactive compound without supression of the background radioactivity. All data were recorded on magnetic tape to permit subsequent selection of the technical parameters required for the reproduction of an image of optimum contrast and intensity. The pulse integrator included in the instrument was used to assess radioactivity in both kidneys during each scanning. Results were expressed as the ratio of renal radioactivity at a given time (Ct) to renal radioactivity after five minutes (C5); this value was called the renal concentration index (RCI). To distinguish bilateral renal ischaemia from essential arterial hypertension, the RCI of the right kidney (RK) was divided by the RCI of the left kidney (LK), which gave a comparative index for the two kidneys (Icomp.). The authors conclude that the procedure as described could be used as a selective test for arterial hypertension of renovascular origin, since it furnishes an index directly correlated with the individual renal plasma flow and a series of images representative of the regional blood flow in each of the kidneys. As renal concentration of chlormerodrin requires both good renal blood flow and tubular cell efficiency, in cases of unilateral tubular necrosis results will be obtained similar to those for cases of unilateral renal ischaemia. The authors
Computer-assisted static/dynamic renal imaging with [197Hg] chlormerodrin and [/sup 99m/Tc] pertechnetate was evaluated prospectively as a screening test for renovascular hypertension. Results are reported for 51 patients: 33 with benign essential hypertension and 18 with renovascular hypertension, and for 21 normal controls. All patients underwent renal arteriography. Patients with significant obesity, renal insufficiency, or renoparenchymal disease were excluded from this study. Independent visual analyses of renal gamma images and time-activity transit curves identified 17 of the 18 patients with renovascular hypertension; one study was equivocal. There were five equivocal and three false-positive results in the essential hypertension and normal control groups. The sensitivity of the method was 94% and the specificity 85%. Since the prevalence of the renovascular subset of hypertension is approximately 5%, the predictive value is only 25%. Inclusion of computer-generated data did not improve this result. Accordingly, this method is not recommended as a primary screening test for renovascular hypertension
The first use of a radioactive tracer to study lung function was made by Knipping and others in 1955. They used radioactive 133Xe (xenon) gas as an inhalation agent in a patient with lung cancer and found that distal to a tumor no radioactivity was detected indicating no ventilation although chest x-rays appeared as if there was active ventilation. Subsequently with advance in technology a number of radioactive gases such as 81mKr (krypton) and cyclotron produced 15O2 (oxygen), 11C (carbon) and 13N2 (nitrogen) became available to assess regional lung function. The advantages of these gases are manifold, but their utility is mostly limited due to high cost. An alternative to the use of radioactive gases to study regional ventilation is the use of particulate radioactive aerosol. Radioaerosol inhalation lung imaging technique was developed in 1965 almost simultaneously by Taplin and others and Pircher and others just 2 years following Taplin's invention of 131I-MAA for perfusion lung imaging. Their main aim was to use 131I-human serum albumin (HSA), and 99mTc-HSA, 131I-rose bengal, 197Hg-chlormerodrin and colloidal 198Au as agents for radioaerosol generation, and Taplin himself preferred 198Au colloids for serial studies from economical reasons. Already in 1965, however, Taplin said that the best agent would be 99mTc-HSA. Pircher used 131I-HSA aerosol. Taplin already noted at that time that the inhaled aerosol was removed from the lungs mainly by ciliary action and that it was not absorbed either from the lungs or the intestine. Anyway it is noteworthy that the idea of radioaerosol inhalation lung imaging was proposed soon after the advent of perfusion lung imaging. Besides 131I-HSA and colloidal 198Au, the following agents have been or are currently being used. The superiority of 99mTC over other radioisotopes used in the past is beyond dispute