Exposures II Chapter 25

1. Image acquisition

2. Image processing

3. Image archiving

4. Image display

5. Image analysis

5 steps of imaging process

1. Film (hard copy)

2. Monitor (soft copy)

How ever it is acquired is how it should be viewed to NOT lose resolution.

What are two ways in which image may be processed?

• Stored on film library

• Stored electronically (cloud storage)

What are two ways in which image may be archived?

1. Viewbox

2. Monitor

What are two methods of image display?

Many factors acting upon each other go into the creation of the final image.

• When a problem with image quality is identified, each contributing factor must be determined and corrected before a repeat exposure is made.

What is the pyramid problem?

Image analysis

Analyze image for quality

Diagnose image for quality

Scope of practice for the radiographer:

Produce diagnostic image

Duty of the radiographer to the radiologist:

Do no harm while getting diagnostic image

• Use good judgement to pt’s capability

• ALARA

Duty of the radiographer to the patient:

1. Narrow search

2. Seek hypothesis

3. Seek more information

4. Evaluate hypothesis

4 steps of diagnostic process:

Acceptance limits

Standards for image evaluation in terms of image quality

Wide acceptance limits

A wide range of images are considered acceptable for diagnosis

Narrow limits

Fewer variances from perfect image are considered acceptable.

• Overexposure

• Low contrast (long scale, many shades of grey with few difference in between)

What type of exposure and contrast are wide acceptance limits skewed towards?

Techs would become perfectionist = increases repeats

Disadvantage of narrow acceptance limit

Techs can become sloppy = decreases image quality

Disadvantage of wide acceptance limit