Radiography Exam Radiography 4 — Questions and Answers
Question 1: Which radiation protection principle involves limiting exposure to only what is needed for diagnosis?
- Shielding
- ALARA (Correct answer)
- Distance
- Collimation
Correct answer: ALARA
ALARA (As Low As Reasonably Achievable) is the guiding principle of radiation protection that mandates minimizing patient and occupational dose.
Question 2: On a PA chest radiograph, the carina should normally be located at which vertebral level?
- T4-T5 (Correct answer)
- T6-T7
- T9-T10
- L1-L2
Correct answer: T4-T5
The carina (tracheal bifurcation) is normally located at the level of T4-T5 on a PA chest radiograph.
Question 3: What type of film/screen combination is used to reduce patient dose while maintaining image quality?
- Slow-speed, small grain
- High-speed, large grain
- Medium-speed, no screen
- Fast-speed, rare earth screens (Correct answer)
Correct answer: Fast-speed, rare earth screens
Rare earth fast-speed screens require less radiation to produce adequate density, significantly reducing patient dose compared to calcium tungstate systems.
Question 4: Which positioning error causes the trachea to appear shifted to the left on a PA chest radiograph?
- Patient rotated with left side closer to detector
- Patient rotated with right side closer to detector (Correct answer)
- Patient in expiration
- Incorrect CR angulation
Correct answer: Patient rotated with right side closer to detector
When the patient is rotated with the right side closer to the detector, the right sternoclavicular joint appears larger and the trachea can appear shifted to the left.
Question 5: The term 'OID' in radiography stands for what?
- Object-Image Distance (Correct answer)
- Output Intensity Differential
- Optical Image Density
- Oblique Imaging Direction
Correct answer: Object-Image Distance
OID (Object-Image Distance) is the distance between the object being radiographed and the image receptor, which affects magnification and recorded detail.
Question 6: Which chest pathology would appear radiopaque (white) on a PA chest radiograph?
- Pneumothorax
- Emphysema
- Pleural effusion (Correct answer)
- Hyperaeration
Correct answer: Pleural effusion
Pleural effusion accumulates fluid in the pleural space, which attenuates x-rays and appears as a white (radiopaque) opacity on the radiograph.
Question 7: What is the primary advantage of digital radiography (DR) over computed radiography (CR)?
- Lower equipment cost
- Immediate image acquisition without plate processing (Correct answer)
- Better spatial resolution in all cases
- Smaller file sizes
Correct answer: Immediate image acquisition without plate processing
DR systems capture images directly without the intermediate step of processing an imaging plate, providing immediate image display and improved workflow efficiency.
Radiography Exam Radiography 4
Which radiation protection principle involves limiting exposure to only what is needed for diagnosis?