Patient As Emitter

Question 1

What is attenuation in the context of x-ray beams?

Answer 1

The reduction in the total number of x-ray photons remaining in the beam after passing through a given thickness of material

Attenuation occurs due to absorption and scattering of x-ray photons by the material.

Question 2

What are the two main types of interactions that lead to x-ray attenuation?

Answer 2

• Photoelectric effect
• Scatter (Compton and Coherent)

These interactions determine how many photons are absorbed or scattered as the x-ray beam passes through different materials.

Question 3

What factors must be increased due to differences in tissue composition when using x-ray technology?

Answer 3

• Atomic number
• Tissue thickness
• Tissue density

These factors affect the quantity and quality of the x-ray beam required for effective imaging.

Question 4

Which tissue type attenuates x-ray beams the most?

Answer 4

Bone

Bone has a higher atomic number and density compared to fat or muscle, leading to greater absorption of x-ray photons.

Question 5

What four major substances account for the absorption of x-rays in the human body?

Answer 5

• Air
• Fat
• Muscle
• Bone

These substances vary in their atomic numbers and densities, affecting how x-rays are absorbed.

Question 6

What is subject density in radiography?

Answer 6

Refers to the impact that the subject (patient) has on IR exposure

Increased density in the subject leads to increased absorption of x-rays and decreased exposure to the image receptor.

Question 7

What does subject contrast refer to?

Answer 7

Difference in adjacent exposure levels of a recorded image due to differences in the absorption of the x-ray beam

Greater differences in absorption lead to higher subject contrast in imaging.

Question 8

What is spatial resolution in imaging?

Answer 8

The ability of an imaging system to differentiate between two nearby objects

This is crucial for accurately identifying structures within the body.

Question 9

What is subject distortion?

Answer 9

Misrepresentation of the size and shape of the structure of interest

Question 10

What is pathology in medical science?

Answer 10

Concerned with all aspects of disease, including structural and functional changes caused by disease processes

Question 11

What are additive conditions in radiology?

Answer 11

Diseases that cause the affected body tissue to increase in thickness, effective atomic number, and/or tissue density

These conditions make tissues harder to penetrate with x-rays.

Question 12

What is a common effect of an additive condition like edema?

Answer 12

Increases tissue thickness and may alter composition

Edema can significantly affect x-ray absorption characteristics.

Question 13

What are destructive conditions in radiology?

Answer 13

Diseases that cause the affected body tissue to decrease in thickness, effective atomic number, and/or tissue density

These conditions make tissues easier to penetrate with x-rays.

Question 14

Name two examples of destructive conditions.

Answer 14

• Emphysema
• Pneumothorax

Both conditions result in decreased tissue density, affecting x-ray absorption.

Question 15

Fill in the blank: The primary factor affecting the sharpness or detail of an image is the distance between the structure of interest and the _______.

Answer 15

IR (Image Receptor)

OID (Object-to-Image Distance) is critical in determining image quality.

Question 16

True or False: Increased density in the subject leads to increased IR exposure.

Answer 16

False

Increased density leads to increased absorption, resulting in decreased IR exposure.

Question 17

What does the term ‘subject detail’ refer to in imaging?

Answer 17

The ability of an imaging system to differentiate between two nearby objects

This is influenced by factors such as OID and SID (Source-to-Image Distance).