Nuclear Medicine and Imaging Techniques

A series of flashcards covering key concepts related to nuclear medicine, imaging techniques, and related principles.

What radioactive material is used in Nuclear Medicine to identify regions of uptake in the body?

Radioactive isotopes are used in Nuclear Medicine.

What does the term 'unstable isotopes' refer to in nuclear medicine?

Isotopes that decay to become more stable and emit radiation during the process.

What is fluorodeoxyglucose (FDG) used for in nuclear imaging?

FDG is used as a radiopharmaceutical because the body metabolizes glucose, allowing visualization of tumors.

How is radioactive decay described mathematically?

By the equation N(t) = N0 e^{-λt} where λ is the decay rate constant.

What type of decay is alpha decay associated with?

Alpha decay is associated with the emission of helium nuclei.

What is the purpose of using collimators in nuclear imaging?

Collimators are used to ensure that only certain gamma rays are detected, enhancing image quality.

How does SPECT differ from PET in terms of acquisition?

SPECT requires the camera to rotate to get projections, while PET acquires all projections simultaneously.

What is the primary detection method in PET?

PET detects gamma rays resulting from positron annihilation events.

What type of imaging does planar scintigraphy provide?

Planar scintigraphy provides a single 2D image for whole-body screening.

Why can tumors be detected using FDG?

Tumors have higher metabolic activity and therefore consume more 'sugar' (glucose), which is tracked by FDG.

What is the relationship between the number of protons and neutrons in isotopes?

Isotopes have the same number of protons but different numbers of neutrons.

What happens to gamma rays during Compton scattering?

Gamma rays may change direction, complicating the detection of their source.

What is the typical time for scintillation decay in detectors?

The intensity of the scintillation decays approximately exponentially in time, with a decay time constant of less than 1 µs.

What can affect the spatial resolution of a gamma ray detector?

The resolution of a gamma ray detector is determined by collimator spacing and the location of the object.

What is the function of photomultipliers in gamma cameras?

Photomultipliers detect flashes of light from scintillator crystals and amplify the signal.

How does the half-life of a radionuclide impact its use in radiopharmaceuticals?

Due to short half-lives, radionuclides require preparation just before use to ensure effectiveness.

What is the effect of the detector's distance from the source on image quality?

The further the source, the blurrier the image; this affects spatial resolution.