A small amount of stannous chloride (SnCl2) is added to a vial containing a radiopharmaceutical precursor, such as pertechnetate (TcO4^-).
The stannous ions act as a reducing agent, converting TcO4^- to a reduced form of technetium (Tc-99m).
The radiotracer, now in the form of Tc-99m, can be easily incorporated into red blood cells or other carriers.
Technetium-99m (Tc-99m) undergoes a type of nuclear decay known as an isomeric transition when it emits gamma radiation. Specifically, Tc-99m undergoes an isomeric transition to its more stable state, technetium-99 (Tc-99), through the emission of gamma rays.
The isomeric transition involves a change in the nuclear energy state of the atom without a change in its chemical properties. In the case of Tc-99m, the metastable state (m) refers to a higher-energy state with a relatively short half-life, and the isomeric transition involves the release of a gamma-ray photon as the nucleus transitions to a lower-energy state.
The gamma rays emitted during the isomeric transition of Tc-99m are of diagnostic interest in nuclear medicine. Tc-99m is widely used as a radiopharmaceutical in various medical imaging procedures, including single-photon emission computed tomography (SPECT). The emitted gamma rays are detected by gamma cameras to create images that provide valuable diagnostic information about the structure and function of organs and tissues in the body.
In the Compton effect, a photon interacts with an outer shell electron, resulting in the ejection of the electron and a scattered photon with reduced energy.
Compton scatter is a significant contributor to image noise. It can result in scattered photons reaching the detector and degrading image contrast.
Compton scatter is more likely to occur with higher-energy photons, such as those around 140 keV.
The photoelectric effect is more pronounced at lower energies and is characterized by the complete absorption of a photon by an inner-shell electron, leading to the ejection of the electron.
The Photoelectric Effect is particularly important in medical imaging applications using low-energy X-rays, where it contributes to contrast in radiographic images.
Mnemonic: Compton is with COmpletely More energy PhoTONs (Compton scatter is more likely to occur with higher-energy photon)
photoeLEctric absorbs aLL Lower Energies
A vial containing 32 millicuries is emitting radiation at a rate of 1 roentgen per hour at a distance of 1 meter. If a technologist stands at a distance of 2 meters from the vial, how much radiation (in roentgens) does the technologist receive during a 15-minute period?
I have tried to make a mnemonic for nasal cartilage septal fracture by making some association with the name
Jarjaway fracture = make me think pike George is away. That he means he walked on some path and paths are generally horizontal. So fracture is horizontal. And for horizontal fractures we need blow from front
Chevalier fracture = makes me think of shovel and you know when it is used it is struck on the ground almost inclined or vertical. So vertical fracture and for that fracture we need blow from below
I hope these associations work for you
InShaAllah
Thank you❤
