Radiology and Imaging
What the exam tests
Radiology and Imaging tests radiation safety, positioning, exposure technique, image quality, contrast studies, and basic ultrasound orientation.
Core rules
- ALARA: time, distance, shielding. Wear lead apron and gloves, use collimation, and never hold a patient with unprotected hands.
- Take orthogonal views: lateral and ventrodorsal or dorsoventral.
- Exposure factors: kVp controls penetration and contrast; mAs controls density and quantity. mAs = mA × time.
- Position for the anatomy: true lateral, limbs extended, head straight, no rotation.
- Label images with patient and date; review for motion, positioning, and artifact before the patient leaves.
Worked example
A technique chart lists 300 mA and 0.05 s. mAs = 300 × 0.05 = 15. If the time is increased to 0.10 s, mAs becomes 30, doubling the exposure. Adjust one factor at a time and record the change.
Traps
- Failing to collimate or shield, increasing scatter and dose.
- Accepting a rotated or motion-blurred image because it looks acceptable.
- Using the same technique for all patients regardless of thickness.
- Forgetting to remove collars, leads, or bandage material that obscure anatomy.
- Not warning owners about contrast reactions or renal risk.