DEXA Radiation Safety & Patient Preparation 5

Question 1

A patient who weighs 350 lbs (159 kg) arrives for a DEXA scan. What is the primary concern the technologist should address first?

Accepted Answer

The patient may exceed the table weight limit of the DEXA system

Answer

Most DEXA tables have a weight limit (commonly 300–450 lbs), and exceeding it is a safety concern for both the patient and equipment.

Question 2

Which of the following actions demonstrates proper infection control during DEXA patient preparation?

Accepted Answer

Wiping the scan table with an approved disinfectant between patients

Answer

Disinfecting the scan table surface between patients is standard infection control practice in all diagnostic imaging environments.

Question 3

The T-score threshold defined by the WHO for diagnosing osteoporosis is:

Accepted Answer

-2.5 or below

Answer

The WHO defines osteoporosis as a T-score of -2.5 or lower, indicating bone density 2.5 standard deviations below the young adult mean.

Question 4

A patient asks if they need to fast before their DEXA scan. The correct response is:

Accepted Answer

No fasting required, but avoid calcium supplements on the morning of the scan

Answer

Patients should not fast before DEXA, but are advised to avoid calcium supplements on the day of the scan as they can minimally affect results.

Question 5

Scatter radiation from a fan-beam DEXA system is greater than from a pencil-beam system. What does this mean for staff safety?

Accepted Answer

Staff should exit the room or stand behind a barrier during fan-beam scans

Answer

Fan-beam DEXA produces more scatter radiation than pencil-beam, so technologists should not stand in the direct scatter field during acquisition.

(DEXA) DEXA Bone Density Scan Certification Practice Test