Question

4 Select a PET Neologc procedure and briefly describe what pharmaceutical is used and how the image is interpreted. s. What are the different types of scintillation crystals available for PET imaging? Which is the crystal of choice currently for routine PET imaging and why? What is a relmbursable PET procedure? Give an example of such a procedure.

Answer 1

4) PET: positron emission tomography, it is a powerful tool for invivo imaging investigation of human brain function it provides noninvasive quantification of brain metabolism , receptros binding of various neurotranamitter systems and alterations in regional blood flow, it is a type of nuclear medicine procedure so asmall amount of a radioactive substances called a redionuclide is used to perform the procedure, the PET works by using a scanning device with a large hole at its center to detect positrons emitted by a redionuclide in the organ or tissue examined, in neurological scan radiotracers used in scan are made by attaching a radioactive atom to chemical substances that are used naturally by the particular organ or tissue during its metabolic process so in the neurological scan flurorodeoxyglucose there radioactive atom is applied toglucose because the brain uses glucose for its metabolism , and then the radionuclide is adminstered into a vein through an intravenous line then the pet scanner slowly moves overr the part of the body being examined positrons are emitted by the breakdown of the radionuclide and the gamme rays are created during the emission of positrons and the scanner then detects the gamma rays a computer analyzes the gamma rays and uses the information to create an image map of the organ or tissue being studies the amount of the radionuclide collected in the tissue affects how brightly the tissue appears on the image and indicates the levle of organ or tissue function, in various parkinsonian syndromes also exhibit different patterns of cerebral gluose metabolism , fluoroglucose pet in parkinsons disease reveals normal or increased glucose metabolism in striatum but decreased metabolism in temporopaietal areas etc.the intrepreting the pet scan : the images of brain pet scan appear as multicoloured images of the brain ranging from darkblue to deep red , areas of the active brain activity cme up in warmer color such as yellow and red etc. 5)Different types of scintillation crystals available for PET imaging are thallium doped sodium iodide and bismuth germanate it is widespread use because in pet inorganic scintillator crystals are used to record gamma rays produced by the annihilation of positrons emmitted by injected tracers the ultimate performance of the camera is strongly tied to both the physical and scintillation properties of the crystals, and the recently developed scintillators crystals cerium doped lutetium oxyorthosilicate appears to surpass all preiously used materials in most repects and promises to be the basis for the next generation of pet cameras. 6)Reimbursal PET procedure: private insurance or medicare typically covers PET procedures for the following cancers, noncancer conditions like brain and also cardiac , the coverage for pet with F-18 Fluorodeoxyglucose and PET with sodium fluoride F-18 , In the CMS proposal indicated that medicare reimbursement for thses cancers could be obtained under the cms coverage if the patients referring physician and the pet providers submitted data to a clinical registry to assess the impact of pet on cancer patient management.