Radiation Protection, Hazards and Contrast Media MCQs

Radiology · 21 free questions with answers & explanations.

1. A patient with a history of severe contrast allergy and diabetes mellitus on metformin is scheduled for a contrast-enhanced CT of the abdomen. Regarding metformin and iodinated contrast media, the primary concern is:
2. The principle of ALARA in radiation protection stands for 'As Low As Reasonably Achievable.' The three basic principles of external radiation protection to minimize dose are:
3. A patient develops generalized urticaria and mild bronchospasm within 5 minutes of intravenous iodinated contrast injection. According to ACR guidelines, this constitutes a:
4. Which of the following patients presents the HIGHEST risk for contrast-induced nephropathy (CIN) from iodinated contrast administration?
5. In radiation protection, the concept of 'ALARA' stands for:
6. Gadolinium-based contrast agents (GBCAs) are contraindicated in patients with severe renal failure (eGFR <30) primarily because of the risk of:
7. A patient receives 10 mGy of absorbed dose to the thyroid from X-rays and 2 mGy to the gonads from neutrons. If the radiation weighting factor for X-rays is 1 and for neutrons is 20, what are the respective equivalent doses?
8. A patient with a history of seafood allergy and previous mild reaction to iodinated contrast is scheduled for an emergency CT with contrast. What is the most appropriate premedication regimen to reduce risk of repeat reaction?
9. The 'ALARA' principle in radiation protection stands for:
10. A patient with eGFR 28 mL/min/1.73m² (CKD stage 4) requires urgent contrast-enhanced CT for suspected PE. The iodinated contrast agent required for CTPA poses the risk of contrast-induced nephropathy (CIN). Which preventive measure has the STRONGEST evidence for reducing CIN in high-risk patients?
11. A patient develops an acute severe allergic-like reaction to iodinated contrast medium 15 minutes after IV administration, with urticaria, bronchospasm, hypotension, and loss of consciousness. This reaction is classified as anaphylactoid (non-IgE mediated). What is the FIRST-LINE drug treatment?
12. Gadolinium-based contrast agents (GBCAs) are used for MRI. Nephrogenic systemic fibrosis (NSF) is a severe complication of GBCAs in patients with renal failure. Which physicochemical property of the GBCA is MOST closely associated with the risk of NSF?
13. In radiation protection, the effective dose (in Sieverts) is calculated to compare radiation risks from different exposures and different body parts. The organ weighting factor (wT) for the gonads in the ICRP 103 (2007) recommendations is:
14. A patient with an estimated GFR of 28 mL/min/1.73m² requires contrast-enhanced CT. The MOST appropriate iodinated contrast agent strategy to reduce the risk of contrast-induced nephropathy (CIN) is:
15. Regarding gadolinium-based contrast agents (GBCAs) and nephrogenic systemic fibrosis (NSF), which agent group carries the LOWEST risk due to its macrocyclic and ionic structure?
16. The annual permissible radiation dose limit for radiation workers (occupational) as per IAEA guidelines is:
17. Which iodinated contrast agent parameter BEST predicts the risk of contrast-induced acute kidney injury (CI-AKI)?
18. According to ICRP recommendations, what is the annual effective dose limit for radiation workers (occupationally exposed individuals) in a 5-year average?
19. A patient develops widespread urticaria and laryngeal oedema 20 minutes after IV injection of iodinated contrast. Which pathophysiological mechanism is PRIMARILY responsible for this reaction?
20. Nephrogenic systemic fibrosis (NSF) following MRI with gadolinium contrast is MOST strongly associated with which patient group?
21. A patient with serum creatinine 2.8 mg/dL (eGFR 22 mL/min/1.73m²) requires CT pulmonary angiogram for suspected massive PE. Regarding contrast-induced nephropathy (CIN) and gadolinium, the most evidence-based management is: