Frequency of CT Examinations in Malta

The purpose of this survey was to provide details and frequency data on CT examinations in Malta, and identify commonly requested CT examinations. Future work will establish Diagnostic Reference Levels (DRLs) in these areas. Participation of 57% was garnered encompassing CT units from both public and private hospitals comparing well with other surveys. Three major CT manufacturers were included encompassing four different models. A broad classification using European guidelines was adopted to enable international comparison of frequencies. Data were collected by a questionnaire based on the internationally recognized NRPB W67 guideline, and obtained from the Radiology Information Systems of the hospitals for the period January to December 2008. CT comprised 8.85% of the total ionizing radiation examinations. CT of the head is the most frequently requested examination at 43%. This is higher than in Spain (38%), the United Kingdom (35%), and Ireland (41%) but less than in Wales (50%). The abdomen and pelvis in Malta (33%) is much more frequently requested than in other countries (12%-22%), whereas the thorax is similar to other countries (9%). CT distribution data in Malta has identified differences to other countries. Ongoing work on DRLs will further elucidate the causal factors and enable the establishment of collective doses. The abdomen and pelvis examinations demonstrate a larger frequency and hence a large potential for optimization. A comparison with European and worldwide examination distributions has demonstrated discrepancies in certain CT examinations indicating areas for dose reduction.