Showing posts with label Mnemonics. Show all posts
Showing posts with label Mnemonics. Show all posts

Thursday, December 14, 2023

equivalent dose, exposure, activity units mnemonic for nuclear medicine boards

 https://youtube.com/shorts/-7pQUPw9UkU

Half life of PET radiotracers mnemonic

Theory of equilibrium mnemonic for nuclear medicine boards

 https://www.youtube.com/shorts/QVdlXnw9mXc



Atomic number, mass number mnemonic for chemistry

Dobutamine dosing for cardiac stress test mnemonic

Radioisotopes in nuclear cardiology produced by cyclotron

NRC dose limit for members of the public mnemonic

See video here: https://youtube.com/shorts/T3VLOStIMQc?si=txskgKX4-AtdhiS0


The total effective dose equivalent to individual members of the public from the licensed operation does not exceed 0.1 rem (1 mSv) in a year, exclusive of the dose contributions from background radiation, from any administration the individual has received, from exposure to individuals administered radioactive material and released under § 35.75, from voluntary participation in medical research programs, and from the licensee's disposal of radioactive material into sanitary sewerage in accordance with § 20.2003

Friday, December 8, 2023

Deterministic vs Stochastic effects

Deterministic effects (or tissue reactions) of ionizing radiation are related directly to the absorbed radiation dose and the severity of the effect increases as the dose increases. 

Example: Cataracts

Mnemonic: DDD Deterministic severity Determined by Dose

Stochastic effects of ionizing radiation are chance events, with the probability of the effect increasing with dose, but the severity of the effect is independent of the dose received. Stochastic effects are assumed to have no threshold. 

Example: Cancer

Mnemonic:
Stochastic Severity No
Probability So

Photolectric effect and Compton scatter

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 


Sunday, December 3, 2023

Inaccurate camera settings, incorrect photopeak, flood field


Inaccurate camera settings, incorrect photopeak, flood field for nuclear boards

The pulse height analyzer (PHA) measures in-coming signals and enables signals of a specific energy range ("window") to be recorded while excluding all other signals.

If the window set slightly below the photopeak, the honey comb artifact with "hot" spots over each photomultiplier tube is characteristic.