Half life of Iridium 192
Answer: c) 73.8 daysISOTOPES USED IN MEDICINEReactor Radioisotopes (half-life indicated in brackets):Molybdenum-99 (66 h): Used as the 'parent' in a generator to produce technetium-99m.Technetium-99m (6 h): Used in to image the skeleton and heart muscle in particular, but also for brain, thyroid, lungs (perfusion and ventilation), liver, spleen, kidney (structure and filtration rate), gall bladder, bone marrow, salivary and lacrimal glands, heart blood pool, infection and numerous specialized medical studies.Uses of Technetium 99 tagged RBC's:Commonly indicated in Acute Lower Gastrointestinal Bleeding.Relatively sensitive & very specific imaging method for noninvasive diagnosis of liver hemangioma.Measurement of left ventricular ejection fraction. Assessment of regional wall motion (left and right ventricles).Chromium-51 (28 d): Used to label RBC's and quantify gastro-intestinal protein loss.Cobalt-60 (10.5 months): Formerly used for external beam radiotherapy.Copper-64 (13 h): To study genetic diseases affecting copper metabolism. Eg: Wilson's and Menke's diseases.Dysprosium-165 (2 h): Used as an aggregated hydroxide for synovectomy treatment of arthritis.Erbium-169 (9.4 d): Use for relieving arthritis pain in synovial joints.Holmium-166 (26 h): Being developed for diagnosis and treatment of liver tumours.Iodine-125 (60 d): Used in brachytherapy (prostate and brain), to evaluate the filtration rate of kidneys and to diagnose DVT in the leg. It is also used in radioimmuno-assays to show the presence of hormones in tiny quantities.Iodine-131 (8 d): Used in treating thyroid cancer, imaging the thyroid; in diagnosis of abnormal liver function, renal (kidney) blood flow and urinary tract obstruction. A strong gamma emitter, but used for beta therapy.Iridium-192 (74 d): Supplied in wire form for use as an internal radiotherapy source for cancer treatmentIron-59 (46 d): Used in studies of iron metabolism in the spleen.Lutetium-177 (6.7 d): emits just enough gammas for imaging while the beta radiation does the therapy on small (eg endocrine) tumours. Its half-life is long enough to allow sophisticated preparation for use.Palladium-103 (17 d): Used to make brachytherapy permanent implant seeds for early stage prostate cancer.Phosphorus-32 (14 d): Used in the treatment of polycythemia vera (excess red blood cells). Beta emitter.Potassium-42 (12 h): Used for the determination of exchangeable potassium in coronary blood flow.Rhenium-186 (3.8 d): Used for pain relief in bone cancer. Beta emitter with weak gamma for imaging.Rhenium-188 (17 h): Used to beta irradiate coronary arteries from an angioplasty balloon.Samarium-153 (47 h): Sm-153 is very effective in relieving the pain of secondary cancers lodged in the bone, sold as Quadramet. Also very effective for prostate and breast cancer. Beta emitter.Selenium-75 (120 d): Used as seleno-methionine to study the production of digestive enzymes.Sodium-24 (15 h): For studies of electrolytes within the body.Strontium-89 (50 d): Very effective in reducing the pain of prostate & bone cancer. Beta emitter.Xenon-133 (5 d): Used for pulmonary (lung) ventilation studies.Ytterbium-169 (32 d): Used for cerebrospinal fluid studies in the brain.Ytterbium-177 (1.9 h): Progenitor of Lu-177.Yttrium-90 (64 h): for brachytherapy and as silicate colloid for relieving pain of arthritis. Pure beta emitter.Radioisotopes of caesium, gold and ruthenium are also used in brachytherapy.
17 days
60 days
73.8 days
5.26 years
Fundamentals In Radiology