[Awareness of radiation exposure of thoracic CT scans and conventional radiographs: what do non-radiologists know?]

Abstract

Purpose: Assessment of the knowledge of non-radiological physicians concerning radiation exposure during radiological procedures on the thorax.

Material and methods: 124 non-radiological physicians from the departments of surgery, internal medicine, anesthesiology, and neurology at a university hospital were questioned during a four-week period using a standardized questionnaire as to the effective dose (ED) of different radiological procedures on the thorax. The interviewees were asked to estimate the ED of chest X-rays and CT examinations and to compare these with the ED of other radiological methods. Length of professional experience, field of clinical training, and hierarchical position were also documented. The T-test and chi-square test were used for statistical analysis.

Results: 119/124 (96.0 %) physicians with an average work experience of 8.2 years (0.3-32 years) were willing to participate. 47/119 (39.5 %) correctly estimated the ED of conventional chest X-ray (0.01-0.1 mSv), and 40/119 (33.6 %) correctly gauged the ED of adult chest CT (1-10 mSv). The ED of cardiac CT and pediatric chest CT without dose reduction (10-100 mSv) were correctly judged by 31/119 (26.1 %) and 32/119 (26.9 %), respectively. The correct ratio of the ED of chest X-ray to that of chest CT (factor 100-1000) was given by 28/119 (23.5 %), while 86/119 (72.3 %) underestimated the ratio. 50/119 (42.0 %) and 35/119 (29.4 %) correctly stated that the ED of pediatric chest CT without dose reduction and that of cardiac CT are greater than that of adult chest CT. 24/119 (20.2 %) and 10/119 (8.4 %) thought that the ED of low-dose chest CT is smaller than that of chest X-ray or chest MRI, respectively. The length of professional experience, field of clinical training, and hierarchical position of the participants did not have a significant influence on the test results.

Conclusion: Correct estimation of the ED of radiological chest examinations, especially that of CT examinations with a high ED, poses substantial difficulties for non-radiologists regardless of the length of professional experience and field of clinical training. In light of the increase in ordered radiological exams, targeted adaptation of medical school teaching content and promotion of pertinent continuing radiological education seem pressing.