Comprehensive X-ray Physics, Safety, and Image Optimization Quiz

Who discovered X-rays?

Wilhelm Conrad Röntgen

When were X-rays discovered?

1895

Which subatomic particle has a positive charge?

Proton

Which subatomic particle has a negative charge?

Electron

Where are protons and neutrons located?

Nucleus

Why are outer electrons easier to remove?

They are farther from the positively charged nucleus

X-rays demonstrate which concept?

Wave-particle duality

Which has the highest energy?

Short wavelength, high frequency

Shorter wavelength is associated with:

Higher frequency and higher energy

True or False: X-rays have shorter wavelengths and higher frequencies than visible light.

True

Which technical factor primarily controls X-ray quality?

kVp

Which technical factor controls X-ray quantity?

mA

What does kVp primarily control?

Energy and penetration

What does mAs equal?

mA × time

True or False: Doubling mA doubles the number of electrons passing through the tube.

True

Where are X-rays produced?

X-ray tube

Which side of the X-ray tube is negative?

Cathode

Which side of the X-ray tube is positive?

Anode

What is thermionic emission?

Release of electrons when the filament is heated

Why is tungsten used for the filament?

It can withstand very high temperatures

Which side of the X-ray beam is more intense?

Cathode

Where should the thicker portion of the patient be positioned?

Cathode side

True or False: The anode side of the beam is more intense than the cathode side.

False

What happens during the first stage of the exposure switch?

The tube prepares for exposure

What happens during the second stage of the exposure switch?

X-ray exposure occurs

What does ALARA stand for?

As Low As Reasonably Achievable

Which is an example of a stochastic effect?

A chance-based radiation effect

Deterministic effects are characterized by:

A threshold dose

Radiopaque structures appear:

White/light

Radiolucent structures appear:

Black/dark

Which is NOT one of the three cardinal rules of radiation safety?

Increase exposure time

True or False: Increasing distance from the radiation source helps reduce radiation exposure.

True

True or False: ALARA means radiation exposure should be as high as reasonably achievable.

False

What is the purpose of an intensifying screen?

Convert X-ray energy into light to help expose film

What is a latent image?

An invisible image existing before processing

What turns the latent image into a visible/manifest image?

Developer

What is the central ray?

The central portion of the primary X-ray beam

What does collimation do?

Restricts the X-ray beam size

Good collimation generally:

Decreases patient dose and scatter

True or False: Collimation can improve radiographic contrast by reducing scatter.

True

Which four technical factors are controlled in producing the image?

kVp, mA, time, distance

What is the usual kVp range given in the lecture?

40-120 kVp

What happens when kVp is increased?

X-ray energy and penetration increase

What happens when kVp is too high?

Contrast is lost

What happens when kVp is too low?

X-rays cannot adequately penetrate the body part

True or False: The goal is to keep kVp as low as possible while still adequately penetrating the body part.

True

What primarily controls density/quantity?

mAs

If mA is doubled, what happens to the number of electrons?

It doubles

What is the formula for mAs?

mA × time

Which tissue is most radiolucent?

Gas

Put the tissue opacities in order from darkest to lightest.

Gas → Fat → Soft tissue/fluid → Bone → Metal

Which appears the whitest?

Metal

True or False: Bone is more radiolucent than gas.

False

What is Sante's Rule?

cm × 2 + 40 = kVp

A body part measures 4 cm. What kVp should be used according to Sante's Rule?

48 kVp

A body part measures 10 cm. What kVp should be used?

60 kVp

True or False: Sante's Rule is calculated by multiplying body thickness in centimeters by 2 and adding 40.

True

If you need to increase penetration, what should you do to kVp?

Multiply by 1.15

What should you do to decrease penetration?

Multiply by 0.85

True or False: The 15% rule can be used to adjust kVp.

True

What happens if the distance between the tube and receptor is doubled?

Radiation decreases to 1/4

What is the typical tube-to-receptor distance?

40 inches/100 cm

True or False: Doubling the distance decreases radiation to one-fourth.

True

What does CR stand for?

Computed Radiography

What does DR stand for?

Digital Radiography

What does CR use to store the X-ray image?

Imaging plate

What material stores the energy created by X-rays in a CR plate?

Phosphorus

What reads the stored image on a CR plate?

Laser

Which is an advantage of CR?

No chemicals or wet processing

Which is an advantage of DR?

Immediate image display

Which generally provides the sharpest image and allows image manipulation?

Direct digital imaging

True or False: A clinic can switch from film to digital without necessarily replacing the X-ray generator.

True

True or False: Digital radiography completely eliminates artifacts.

False

What is the correct order for manual film processing?

Developer → Rinse → Fixer → Wash → Dry

What is the purpose of the developer?

Develops the latent image

What does the rinse do?

Stops the developing process

What does the fixer do?

Fixes the image and removes remaining emulsion

What is the main component of fixer?

Ammonium thiosulfate

How long is the manual developer step?

4 minutes

How long is manual fixing?

4 minutes

What are the three categories of film artifacts?

Equipment, processing, handling

Which category accounts for approximately 98% of artifacts according to the lecture?

Processing

What is a pick-off artifact?

Emulsion being picked off the film and redistributed

Pi lines are caused by?

Damp rollers

Exhausted developer can cause?

Lack of correct density and contrast

Residual thiosulfate can cause the image to become?

Yellowish

Which is an example of a handling artifact?

Sweaty fingerprints

Which can cause film fog?

Heat or age

True or False: Static electricity can cause an artifact.

True

What is Quality Control?

Making sure equipment works correctly

What is Quality Assurance?

Documentation of quality control steps

Easy way to remember QC:

QC = Check

Easy way to remember QA:

QA = Record/documentation

What should be checked when images are intermittently too light or too dark?

Line voltage

What is the purpose of a half-value layer test?

Determine how much aluminum absorbs half the X-rays produced

Which protective equipment should be checked for cracks or wear?

All of the above