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Technetium (99m Tc) sestamibi is a lipophilic cation which, when injected intravenously into a patient, distributes in the myocardium proportionally to the myocardial blood flow. Single photon emission computed tomography imaging of the heart is performed using a gamma camera to detect the gamma rays emitted by the technetium-99m as it decays.
Many radionuclides used for myocardial perfusion imaging, including rubidium-82, technetium-99m and thallium-201 have similar typical effective doses (15-35 mSv). [17] The Cardiac PET tracer nitrogen-13 ammonia, though less widely available, may offer significantly reduced doses (2 mSv).
Effective doses can range from 6 μSv (0.006 mSv) for a 3 MBq chromium-51 EDTA measurement of glomerular filtration rate to 11.2 mSv (11,200 μSv) for an 80 MBq thallium-201 myocardial imaging procedure. The common bone scan with 600 MBq of technetium-99m MDP has an effective dose of approximately 2.9 mSv (2,900 μSv). [24]
A cardiac specific radiopharmaceutical is administered, e.g., 99m Tc-tetrofosmin (Myoview, GE healthcare), 99m Tc-sestamibi (Cardiolite, Bristol-Myers Squibb) or Thallium-201 chloride. Following this, the heart rate is raised to induce myocardial stress, either by exercise on a treadmill or pharmacologically with adenosine , dobutamine , or ...
Technetium-99m (Tc-99m) can be readily detected in the body by medical equipment because it emits 140.5 keV gamma rays (these are about the same wavelength as emitted by conventional X-ray diagnostic equipment), and its half-life for gamma emission is six hours (meaning 94% of it decays to 99 Tc in 24 hours). Besides, it emits virtually no beta ...
Technetium (99m Tc) exametazime is a radiopharmaceutical sold under the trade name Ceretec, and is used by nuclear medicine physicians for the detection of altered regional cerebral perfusion in stroke [1] and other cerebrovascular diseases.
Before the widespread application of technetium-99m in nuclear medicine, the radioactive isotope thallium-201, with a half-life of 73 hours, was the main substance for nuclear cardiography. The nuclide is still used for stress tests for risk stratification in patients with coronary artery disease (CAD). [56]
Many radiopharmaceuticals use technetium-99m (Tc-99m) which has many useful properties as a gamma-emitting tracer nuclide. In the book Technetium a total of 31 different radiopharmaceuticals based on Tc-99m are listed for imaging and functional studies of the brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood and ...