FIRST CARDIAC COMPUTED TOMOGRAPHY TYPICAL RADIATION DOSE VALUES FROM A SINGLE CENTRE IN NIGERIA: A PILOT STUDY.

Concern regarding radiation dose associated with cardiac computed tomography (CT) still exists and requires the use of diagnostic reference levels for dose optimisation. Typical median doses were established for 58 consented adult patients from a single centre for coronary artery calcium score (CACS) as volume computed tomography dose index (CTDIvol): 5.9 mGy; dose length product (DLP): 86.6 mGy*cm and cardiac CT angiography (CCTA) as CTDIvol: 11.1 mGy; DLP: 190.8 mGy*cm. Wide radiation dose variability in terms of CTDIvol was noted for CACS: 2.7-15.9 mGy, a 6-fold, whereas for CCTA it ranges from 3.8 to 52.8 mGy, a 14-fold. The DLP values for CACS range from 33.2 to 344.2 mGy*cm, which is 10-fold, whereas for CCTA it ranges from 32.8 to 834.9 mGy*cm, a 25-fold. The typical values compared lower than the radiation dose from other countries; however, the wide variability in dose remains a call for concern.