The first dedicated PET/CT centre in Norway was established at the Norwegian Radiumhospital in Oslo in 2005. Knowing that the introductions of PET-isotopes in nuclear medicine give increased occupational radiation dose to the technicians, a study was carried out in order to map the doses to staff members during different working operations and to see if any dose reducing measures were needed. The results of the study are in good agreement with other studies, and a technician dose of 20-25 nSv per injected MBq of 18F seems to be representative for such centres. For an average injected activity of 350 MBq per patient, the dose limit is reached after handling around 3000 patients annually. For an annual number of less than 500 patients at the centre and rotation of the staff, an annual individual dose for the technicians would realistically be less than 2-3 mSv. Even a major increase in the number of patients will not result in individual doses near the ICRP dose limit.

ObjectiveTo explore clinicians’ knowledge and consideration of radiation, in relation to their referral practice and use of referral guidelines for imaging.MethodsA questionnaire was handed out to 213 clinicians in Norway; all responded: 77 general practitioners, 71 hospital physicians and 65 non-physicians (55 manual physiotherapists, 10 chiropractors). Questions concerned weighting of radiation dose, guideline use, referrals unlikely to affect treatment, doses from imaging procedures, ranking of imaging as radiation source, and deterministic and stochastic effects. For radiation knowledge, a total score was aggregated.ResultsThe mean radiation knowledge score was 30.4/71. Most respondents underestimated doses from high-dose imaging, e.g., barium enema (94.7%), chest CT (57.7%) and abdominal CT (52.7%). Limited radiation knowledge was not compensated by using guidelines. Only 20% of physicians and 72% of non-physicians used referral guidelines. Non-physicians weighted radiation dose as being more important than physicians when referring; they also reported fewer referrals as being unlikely to affect treatment. Such referrals and not using guidelines were related to lower weighting of radiation dose but not to radiation knowledge.ConclusionLimited radiation knowledge and guideline use indicate suboptimal justification of referrals. When justifying imaging, weighting of radiation dose may play a larger role than detailed radiation knowledge.

Measurements of the radioactivity in some common building materials in Norway are reported, together with calculations of the gamma-ray exposure from walls of different materials. Model rooms are used in calculations of the mean exposure inside concrete, brick and light-weight expanded clay aggregate buildings. These calculations give very good agreement with previous experimental results. The radiological implications of using building materials with high concentrations of radioactivity are also discussed.

ObjectivesTo explore if the perception of radiologists and radiographers on referral practice differs from that of referring clinicians, and to see if knowledge of radiation issues and referral guidelines differ between these groups.MethodsA questionnaire was handed out to 46 radiologists and 36 radiographers in Norway. Findings were compared to corresponding results from a similar already published study on clinicians. Questions dealt with referrals unlikely to affect treatment as well as respondents’ radiation and referral guideline knowledge.ResultsRadiographers estimated the highest proportion of referrals most unlikely to affect treatment (median 20 %) in comparison to radiologists (10 %) and clinicians (5 %). Lack of time, compensating for limited clinical examination and patient expectations were rated as more important reasons for such referrals by radiologists than by clinicians. Radiologists and radiographers possessed significantly better radiation knowledge than clinicians, and were more familiar with referral guidelines.ConclusionsThe perception of radiologists and radiographers differs from that of clinicians, concerning the use of imaging most unlikely to affect treatment, and the reasons for such referrals. Radiologists and radiographers possess better radiation knowledge than referring clinicians, but all groups have a potential in improving their radiation protection knowledge.Main Messages• Radiographers estimated the highest proportion of referrals most unlikely to affect treatment.• Radiologists rated “getting the patient discharged” as an important reason for such referrals.• Radiologists and radiographers possess significantly better radiation knowledge than clinicians.