Nuclear Medicine and Radiopharmaceuticals Lecture Notes

A collection of flashcards covering key terms and concepts from the lecture on nuclear medicine and radiopharmaceuticals.

Nuclear medicine

A medical specialty that uses radioactive substances for the diagnosis and treatment of diseases.

Radioactivity

The spontaneous emission of radiation from an unstable nucleus, discovered by Henri Becquerel.

Radioactive decay

The process in which an unstable nucleus loses energy by emitting ionizing particles and radiation to form a stable state.

Alpha decay

A type of radioactive decay in which the unstable nucleus emits a helium nucleus (alpha particle / alpha ^4₂He)

Beta decay

A type of radioactive decay in which the nucleus emits an electron or positron.

Gamma decay

A type of radioactive decay in which the nucleus emits a gamma ray or high energy photon.

Radionuclides

Isotopes that are radioactive and decay by emitting alpha, beta, or gamma radiation.

Half-life (T1/2)

The time required for the initial activity of a radioactive substance to reduce by half.

Curie (Ci)

The basic unit for quantifying radioactivity, describes the rate at which nuclei decay

Ci = 3.7 x 10¹⁰ atoms disintegrations per second (dps)

Becquerel (Bq)

A unit of radioactivity

Bq = 1 disintegration per second (dps)

Gamma camera

An electronic device that detects gamma rays emitted by radiopharmaceuticals introduced into the body.

Scintillator

A crystal that converts gamma rays into visible light as part of the gamma camera.

SPECT

Single-photon emission computed tomography, a nuclear medicine tomographic imaging technique using gamma rays.

PET

Positron emission tomography, a diagnostic imaging technique that uses positron emitting radiopharmaceuticals.

Radiopharmaceutical

A radioactive compound used for diagnosis or treatment that is administered to patients.

2 components

• Radioactive = Radionuclide

• Non-radioactive = Pharmaceutical (chosen on the basis of its localization or participation in physiologic function of an organ)

These two components work together (bind) to create a substance that can target specific organs or tissues within the body for imaging or therapeutic purposes.

Radiation safety

Practices to minimize unnecessary exposure to radiation for both patients and healthcare workers.

Artificial radioactivity

Radioactivity that is a consequence of human activity, involving the production of radionuclides.

Radiation measurement

The quantification of radioactivity, often using units such as Curie, milllicurie, microcurie, and Becquerel.

Ionizing radiation

Radiation that carries enough energy to liberate electrons from atoms or molecules, causing ionization.

Protection against radiation

Strategies employed to shield individuals from harmful radiation, such as using lead for gamma rays.