Radiology Tech Flashcards

Which unit is used to measure radiation absorbed dose in SI units?

Answer: Gray

The Gray (Gy) is the SI unit of absorbed dose, equal to 1 joule of energy deposited per kilogram of tissue.

What is the primary purpose of a grid in radiographic imaging?

Answer: Reduce scatter radiation reaching the image receptor

Grids are placed between the patient and image receptor to absorb scattered radiation, improving image contrast.

Which of the following describes the ALARA principle?

Answer: As Low As Reasonably Achievable

ALARA stands for As Low As Reasonably Achievable, guiding practitioners to minimize radiation exposure while maintaining diagnostic image quality.

What does mAs represent in radiographic technique?

Answer: Milliampere-seconds, a measure of X-ray quantity

mAs (milliampere-seconds) is the product of tube current (mA) and exposure time (s), determining the total quantity of X-rays produced.

Which type of X-ray interaction with matter predominates at diagnostic energy levels in soft tissue?

Answer: Compton scatter

Compton scatter is the dominant interaction at typical diagnostic X-ray energies in soft tissue, contributing to image noise and patient dose.

What is the function of the anode in an X-ray tube?

Answer: Receive electrons and produce X-rays

The anode (target) receives high-speed electrons from the cathode, converting a small fraction of their kinetic energy into X-rays.

A radiograph appears too light (underexposed). Which adjustment would most directly correct this?

Answer: Increase mAs

Increasing mAs raises the quantity of X-rays produced, resulting in greater film blackening or detector signal and a properly exposed image.