Technique Chapter 1

X-rays

A form of electromagnetic radiation discovered by Dr. Wilhelm Conrad Roentgen on November 8, 1895.

Erythema

The reddening and burning of the skin, particularly due to radiation exposure.

Wavelength

The distance between two successive points in a wave.

Frequency

The number of waves passing a given point per unit of time.

Photon

A particle of light that X-rays behave like.

Air kerma

The amount of energy deposited in a unit mass of air, expressed in gray (Gy).

Gray (Gy)

The unit of measure for absorbed dose, equivalent to 1 joule of energy absorbed per kilogram of material.

Rem

Radiation equivalent in man, a unit for measuring occupational radiation exposure.

Half-life

The time it takes for the radiation activity of a material to reduce to 50% of its original activity.

ALARA Principle

As Low As Reasonably Achievable; a principle for minimizing radiation exposure.

Properties of X-rays

X-rays are invisible, electrically neutral, travel at the speed of light, cannot be focused, and can penetrate the human body.

Polyenergetic beam

A beam of X-rays that is composed of multiple energies.

Ionization

The process by which radiation removes electrons from atoms, potentially causing damage.

Radiation

Energy emitted in the form of waves or particles.

Radiotherapy

A treatment method that uses ionizing radiation to kill or control cancer cells.

Computed Tomography (CT)

A medical imaging technique that uses X-rays to create detailed cross-sectional images of the body.

Fluoroscopy

A technique that uses X-rays to obtain real-time moving images of the interior of the body.

Dosimeter

A device used to measure an absorbed dose of radiation.

Radiation Shielding

Materials used to protect against exposure to radiation.

Radon

A naturally occurring radioactive gas that can accumulate in homes and buildings.

Radiosensitivity

The susceptibility of cells or tissues to the harmful effects of radiation.

Radiation Therapy

Medical treatment that uses high doses of radiation to kill cancer cells and shrink tumors.

Gamma Rays

A form of high-energy electromagnetic radiation with the highest frequency and energy.