Combining optimized image processing with dual axis rotational angiography: Toward low-dose invasive coronary angiography

Abstract

BACKGROUND: Dual axis rotational coronary angiography (DARCA) reduces radiation exposure during coronary angiography on older x-ray systems. The purpose of the current study is to quantify patient and staff radiation exposure using DARCA on a modality already equipped with dose-reducing technology. Additionally, we assessed applicability of 1 dose area product to effective dose conversion factor for both DARCA and conventional coronary angiography (CCA) procedures. METHODS AND RESULTS: Twenty patients were examined using DARCA and were compared with 20 age-, sex-, and body mass index–matched patients selected from a prior study using CCA on the same x-ray modality. All irradiation events are simulated using PCXMC (STUK, Finland) to determine organ and effective doses. Moreover, for DARCA each frame is simulated. Staff dose is measured using active personal dosimeters (DoseAware, Philips Healthcare, The Netherlands). With DARCA, median cumulative dose area product is reduced by 57% (ie, 7.41 versus 17.19 Gy·cm2). Effective dose conversion factors of CCA and DARCA are slightly different, yet this difference is not statistically significant. The occupational dose at physician’s chest, leg, and collar level are reduced by 60%, 56%, and 16%, respectively, of which the first 2 reached statistical significance. Median effective dose is reduced from 4.75 mSv in CCA to 2.22 mSv in DARCA procedures, where the latter is further reduced to 1.79 mSv when excluding ventriculography. CONCLUSIONS: During invasive coronary angiography, DARCA reduces radiation exposure even further toward low-dose values on a system already equipped with advanced image processing and noise reduction algorithms. For both DARCA and CCA procedures, using 1 effective dose conversion factor of 0.30 mSv·Gy−1·cm−2 is feasible.