Diagnostic imaging radioisotopes

DTPA has also been used in the peptide-based " in-DTPA-octreotide. Octreotide is a shortened peptide analog of somatostatin designed to be more stable in vivo. Radiolabeling of octreotide for diagnostic imaging applications with radioisotopes for PET or SPECT has been investigated,... 

An allied application of radiolabelled anti-tumour monoclonal antibodies is that of diagnostic imaging (immunoscintigraphy). In this case, the radioisotope employed must be a y-emitter (such that the radioactivity can penetrate outward through the body for detection purposes). Although various radioisotopes of iodine have been evaluated, (technetium) is the one... 

Discuss the preparation and use of radioisotopes In diagnostic Imaging studies. 

Technetium-99m is used in diagnostic imaging studies involving the brain. What fraction of the radioisotope remains after 12 hours have elapsed See Table 10.2 for the half-life of technetium-99m. 

The uses of radioisotopes in medicine are extremely important. Certain elements are readily absorbed by particular organs or by the bone in the human body. This is the basis for their use in radiopharmaceuticals (introduced by food or drug intake) to probe the function of human organs diagnostic imaging) or to destroy cancerous cells radiotherapy). An advantage of these techniques is that they are non-invasive. 

The utilization of radioisotopes in the field of nuclear medicine has been promoted for various purposes. Among them, diagnostic applications have had much success during the past two decades. Technetium-99m, thallium-210 and iodine-123, for example, have been used as radioisotopes for imaging studies. 

Radiophannaceuticals are almost ideal diagnostic tools because radioisotope tracers do not alter body physiology, and they permit external monitoring with minimal instrumentation. Presently, there are three major areas of nuclear medicine (1) physiological function studies, (2) radionuclide imaging procedures, and (3) therapeutic techniques. 

The two naturally occurring isotopes of copper are stable to nuclear decay. Nine synthetic radioisotopes have been reported ( Cu, Cu, Cu, Cu, Cu, Cu, Cu, " Cu, Cu) withhalf-hves of those nuclides ranging from 31 s ( Cu) to 2.58 days ( Cu). One isotope has been used for medical diagnostic purposes see Metal-based Imaging Agents) to scan the brain and to study Wilson s disease. This isotope, Cu, has a half-life of 12.7 h (decay modes at 0.571 MeV,... 

Scintillators also play an important role in medical diagnostics [4], X-ray imaging has aiready been dealt with in Chapter 8. In this chapter we will mention the y-iay camera. Radioisotopes are introduced into the body, usually in the form of chemical compounds labeled with a suitable radioactive element. A commonly used one is Tc... 

Radioisotopes are used in medicine in two distinctly different ways dis nosis and therapy. In the diagnosis of internal disorders, physicians need information on the locations of the disorders. An appropriate radioisotope is introduced into the patient s body, either alone or combined with some other chemical, and it accumulates at the site of the disorder. There the radioisotope disintegrates and emits its characteristic radiation, which can be detected. Modern medical diagnostic instruments not only determine where the radioisotope is located in the patient s body but also construct an image of the area. 

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