Experimental Examination Of Radiation Doses From Cardiac And Liver Ct Perfusion In A Phantom Study As A Function Of Organ, Age And Sex

Cardiac and liver computed tomography (CT) perfusion has not been routinely implemented in the clinic and requires high radiation doses. The purpose of this study is to examine the radiation exposure and technical settings for cardiac and liver CT perfusion scans at different CT scanners. Two cardiac and three liver CT perfusion protocols were examined with the N1 LUNGMAN phantom at three multi-slice CT scanners: a single-source (I) and second- (II) and third-generation (III) dual-source CT scanners. Radiation doses were reported for the CT dose index (CTDIvol) and dose-length product (DLP) and a standardised DLP (DLP10cm) for cardiac and liver perfusion. The effective dose (ED10cm) for a standardised scan length of 10 cm was estimated using conversion factors based on the International Commission on Radiological Protection (ICRP) 110 phantoms and tissue-weighting factors from ICRP 103. The proposed total lifetime attributable risk of developing cancer was determined as a function of organ, age and sex for adults. Radiation exposure for CTDIvol, DLP/DLP10 cm and ED10 cm during CT perfusion was distributed as follows: for cardiac perfusion (II) 144 mGy, 1036 mGy center dot cm/1440 mGy center dot cm and 39 mSv, and (III) 28 mGy, 295 mGy center dot cm/279 mGy center dot cm and 8 mSv; for liver perfusion (I) 225 mGy, 3360 mGy center dot cm/2249 mGy center dot cm and 54 mSv, (II) 94 mGy, 1451 mGy center dot cm/937 mGy center dot cm and 22 mSv, and (III) 74 mGy, 1096 mGy center dot cm/739 mGy center dot cm and 18 mSv. The third-generation dual-source CT scanner applied the lowest doses. Proposed total lifetime attributable risk increased with decreasing age. Even though CT perfusion is a high-dose examination, we observed that new-generation CT scanners could achieve lower doses. There is a strong impact of organ, age and sex on lifetime attributable risk. Further investigations of the feasibility of these perfusion scans are required for clinical implementation.