Posts

Showing posts from November, 2023
Image
  Multiplexed PET-CT Imaging Two PET-Tracers Simultaneously   Introduction: Medical imaging techniques such as Positron Emission Tomography (PET) are extensively employed in preclinical and clinical settings. Fluorine-18-fluorodeoxyglucose, or 18F-FDG, is a radiotracer that is used in PET/CT scans as part of cancer care to detect elevated glucose intake, a characteristic of cancer cells. Additionally, a large number of different radiotracers have been created by researchers to target other disease-specific markers. The way PET operates is by identifying two 511 keV annihilation photons that are produced when an electron in the body and a positron released by the radiotracer annihilate. One radiotracer can only be imaged at a time, though, as all PET isotopes emit the same two 511 keV photons. In order to identify signatures from several tracer, successive PET scanning is necessary. However, this approach is expensive, contingent on the tracer degrading enough over ...
Image
  Staff Radiation Protection  in  fluoroscopic procedures 1- Distance : The intensity of scattered radiation is inversely proportional to the distance square . when the staff stand away from the patient during the radiation exposure , they get less scattered radiation.  2-Fluoroscopic Projection:  The scattered radiation is high near the area where the radiation incident . the tube positioning is highly significant in staff dose reduction   the under couch tube position cause most of the scattered radiation to be towards the staff extremities . the overcoach position cause most of the scattered towards the sensitive organs (i.e eye ,...). it is preferable to avoid the over coach position to protect the sensitive organs from the radiation hazard. The lateral position is producing more scattered radiation due to higher patient thickness , and long beam pathway. only 1-5 % of radiation transmit the patient body to the receptor side . i...
Image
The physics of Nuclear Imaging part 1 Outlines: 1-Radiopharmaceuticals 2-Radiopharmaceutical QC 3-Dose Calibrator QC   1-Radiopharmaceuticals: ·        Definition: Radiopharmaceuticals consist of a radioactive isotope, which creates the image, and a pharmaceutical, which determines the physiological behavior of the compound and, therefore, where the signal accumulates to form the image. ·        Properties of ideal radiopharmaceuticals: 1.      Easily and firmly attached to the pharmaceutical at room temperature but has no effect on its metabolism. 2.      Readily available at the hospital site. 3.      A high-specific activity 4.      High target: non-target uptake ratio 5.      Easy and cheap to produce 6.      Non-toxic 7.      Does not alter physiolog...