MODULE 1 - X-ray Imaging System Flashcards

Flashcards about the X-ray Imaging System

What are the main components of the X-ray tube?

Rotating anode, stator, induction motor, glass envelope, bearings, rotor/anode, cathode support block, focusing cup, target, and exit window.

What does the control panel allow you to select in an X-ray system?

Radiation quantity (mA), beam quality (kVp), exposure time (mAs), and Automated Exposure Control (AEC).

What is the purpose of mA (milliamperes) in X-ray imaging?

Controls the quantity or intensity of the X-ray beam; based on tube current.

What does kVp (kilovoltage peak) determine?

The quality or penetrability of the X-ray beam; affects the energy and velocity of electrons.

What is the formula for exposure time?

mA × time (s) = mAs

Why are lockout keys used in X-ray labs?

To restrict unauthorized use and prevent accidental radiation exposure.

What material is the cathode filament made of?

Thoriated tungsten, due to its durability and efficiency in thermionic emission.

What causes the anode to rotate?

Electromagnetic induction motor using stator (outside) and rotor (inside).

What are the standard target/focal spot sizes (FSS) and why are they important?

0.6 mm and 1.2 mm; important for spatial resolution and image sharpness.

Name at least three physical characteristics of X-rays.

Invisible, electrically neutral, no mass, travel at light speed, and can't be focused optically.

What safety strategies help prolong the life of the X-ray tube?

Warm up the tube, avoid overheating, don’t hold the rotor unnecessarily, use lower mA, avoid moving the tube while energized.

What does the glass envelope in the X-ray tube do?

Maintains a vacuum necessary for efficient X-ray production.

What happens when the rotor or bearings fail?

Can lead to overheating, uneven wear, and reduced image quality or tube failure.

What are the objectives of learning the X-ray imaging system?

Define physical attributes of X-rays, select proper mA, time, and kVp, understand anode and cathode roles, and relate mA, kVp, and time to radiation exposure.

What are additional characteristics of X-rays?

Polyenergetic beam, straight-line travel, cause fluorescence, penetrate the body, can be absorbed or scattered, cause secondary radiation, and damage tissue.

What components are found on the cathode side of the X-ray tube?

Filaments and focusing cups.

Why is anode rotation important?

Distributes heat over a larger area to prevent localized overheating and damage.

What does the X-ray tube window (port) do?

It allows the X-ray beam to exit the tube; typically about 5 mm² in size.

What materials are used for the X-ray tube enclosure?

Pyrex glass or a glass/metal combination, to maintain vacuum and withstand heat.

What is the purpose of the focusing cup?

To direct electrons from the filament to a small area on the anode (focal spot).

What is thermionic emission?

The release of electrons from a heated filament (cathode) in the X-ray tube.

Name three components of the X-ray room and tube setup.

Stator, anode (tungsten-rhenium), rotor, cathode, filament, focusing cup, glass port.

What are some protective features of the X-ray tube?

Thermal sensors, oil/air cooling, protective housing, and operational protocols to prevent overheating.

Where are safety resources like lead glass and shielding available?

Radiology Imaging Solutions and Lead X-ray Glass.

What does AEC (Automatic Exposure Control) do?

Automatically determines the correct exposure time to produce optimal image quality while minimizing dose.