Introduction to the Imaging Sciences - Practice Flashcards

A set of vocabulary flashcards covering the history of X-ray discovery, fundamental physics principles, radiologic units of measure, radiographic equipment, and radiation protection basics.

Dr. Roentgen

Born March 27, 1845, in Lennep, Germany, he earned a PhD from the University of Zurich in 1869 and served as Director of the Physics Institute at the University of Wurzburg.

Discovery of X-rays

On November 8, 1895, Dr. Roentgen explored a phenomenon where barium platinocyanide-painted cardboard fluoresced near a powered cathode ray tube.

First Radiograph

Produced by Dr. Roentgen on December 22, 1895.

Thomas Edison

A scientist who discontinued his x-ray experiments after being injured, bringing attention to the dangers of x-rays.

Clarence Dally

Edison's assistant who developed severe radiation burns and eventually died from his injuries; treatment for such burns at the time was often amputation.

Acute radiodermatitis

Radiation burns that were nearly eliminated by 1900 through improved imaging plates, equipment, and techniques.

Fundamental quantities

The three basic units of measure: mass, length, and time.

Derived quantities

Quantities that include velocity, acceleration, force, momentum, work, and power.

Radiologic quantities

Specific measures including dose, dose equivalent, exposure, and radioactivity.

SI Units of Measure (Fundamental)

The metric system units: kilogram for mass, meter for length, and second for time.

Velocity ($v$)

A derived quantity calculated as $v = d/t$, measured in meters per second ($m/s$).

Acceleration ($a$)

A derived quantity calculated as $a = \frac{v_f - v_o}{t}$, measured in meters per second squared ($m/s^2$).

Force ($F$)

A derived quantity calculated as $F = ma$, measured in Newtons ($N$).

Momentum ($p$)

A derived quantity calculated as $p = mv$, measured in kilogram-meters per second ($kg \text{-} m/s$).

Work

A derived quantity calculated as $\text{work} = Fd$, measured in Joules ($J$).

Power ($P$)

A derived quantity calculated as $P = \text{work}/t$, measured in Watts ($W$).

Inertia

The property of an object with mass that resists a change in its state of motion.

Energy

The ability to do work, existing in potential (stored) and kinetic (expended) states.

Coulomb/kilogram ($C/kg$)

A measure of the number of electrons liberated by ionization per kilogram of air; where $1$ coulomb is the charge of $6.24 \times 10^{18}$ electrons.

Roentgen ($R$)

A unit to quantify radiation intensity, equal to the quantity of radiation that produces $2.08 \times 10^9$ ion pairs in a cubic centimeter ($cm^3$) of air; $1 \text{ C/kg} = 3876 \text{ R}$.

Gray ($Gy$)

The SI unit for absorbed dose, representing the quantity of radiation energy absorbed by irradiated tissues.

Rad ($rad$)

The unit used to quantify the biologic effects of radiation on humans and animals; it measures energy deposited in any target tissue or object.

Sievert ($Sv$)

The SI unit used to quantify occupational exposure or dose equivalent, addressing the different biologic effects of different types of ionizing radiation.

Rem ($rem$)

The standard unit for occupational exposure or dose equivalent.

Becquerel ($Bq$)

The SI unit for radioactivity that quantifies the number of individual atoms decaying per second.

Curie ($Ci$)

The standard unit for radioactivity, defined as the quantity of radioactive material in which $3.7 \times 10^{10}$ atoms disintegrate every second.

Kerma

An acronym for 'kinetic energy released per unit mass,' used to describe the quantity of radiation energy delivered to a given point.

Tube head assembly

The apparatus consisting of the x-ray tube, collimator, and tube stand.

Wall unit

Equipment consisting of a vertical rail assembly and a vertical Bucky assembly, used for easy upright examinations.

Control panel

The interface used by radiographers to select the kilovoltage ($kVp$) and milliamperage ($mA$) for x-ray production.

ALARA

An acronym for 'As Low As Reasonably Achievable,' the guiding principle of radiation protection for patients and personnel.

Cardinal principles of radiation protection

The three primary methods for minimizing radiation dose: Shielding, Time, and Distance.

ASRT and ARRT

Professional organizations in imaging sciences: the American Society of Radiologic Technologists and the American Registry of Radiologic Technologists.