Medical Imaging

Which component of a simple x-ray system helps in controlling the size and shape of the X-ray beam?

• High voltage generator

• X-ray tube

• Collimator

• Intensifying screen and film

What is the purpose of the aluminum filter in an x-ray system?

• To restrict the x-rays generated by the x-ray tube

• To remove the low-energy x-rays that would not penetrate the body

• To trap scattered secondary radiation

• To expose the film

What happens to scattered secondary radiation in an x-ray system?

• It strikes the screen phosphor

• It is restricted by the collimator

• It is removed by the aluminum filter

• It is trapped by the grid

What is the unit of absorbed radiation dose?

• Rad

• Rem

• Quality factor (Q)

• X-ray shielding

What is the purpose of collecting and processing many x-ray images in CT scanning?

• To render a three-dimensional image

• To provide cross-sectional views

• To perform CT brain studies

• To conduct cardiac CT

What controls the timing, anode voltage (kV), and beam current (mA) in an x-ray system?

• High voltage dc power supply

• X-ray tube

• Dedicated microcomputer

• Gantry

What is responsible for driving the x-ray tube in an x-ray system?

• Timing controls

• Anode voltage (kV)

• Beam current (mA)

• High voltage dc power supply

Where does the patient lie in an x-ray system?

• Gantry

• X-ray tube

• Tube through the center of the gantry

• Imaging detectors

What is used in Magnetic Resonance Imaging (MRI) to induce and monitor resonance?

• X-ray radiation

• Ultrasound waves

• Large circular magnet

• Gamma rays

In MRI, resonance is associated with the magnetic moment of which nuclei?

• Oxygen atoms

• Carbon atoms

• Hydrogen atoms

• Nitrogen atoms