Published online Oct 26, 2013. doi: 10.4330/wjc.v5.i10.382
Revised: July 25, 2013
Accepted: August 28, 2013
Published online: October 26, 2013
Processing time: 223 Days and 7.9 Hours
AIM: To explore whether computer tomography coronary angiography (CTCA) using iterative reconstruction (IR) leads to significant radiation dose reduction without a significant loss in image interpretability compared to conventional filtered back projection (FBP).
METHODS: A consecutive series of 200 patients referred to our institution to undergo CTCA constituted the study population. Patients were sequentially assigned to FBP or IR. All studies were acquired with a 256-slice CT scanner. A coronary segment was considered interpretable if image quality was adequate for evaluation of coronary lesions in all segments ≥ 1.5 mm.
RESULTS: The mean age was 56.3 ± 9.6 years and 165 (83%) were male, with no significant differences between groups. Most scans were acquired using prospective ECG triggering, without differences between groups (FBP 84% vs IR 82%; P = 0.71). A total of 3198 (94%) coronary segments were deemed of diagnostic quality. The percent assessable coronary segments was similar between groups (FBP 91.7% ± 4.0% vs IR 92.5% ± 2.8%; P = 0.12). Radiation dose was significantly lower in the IR group (2.8 ± 1.4 mSv vs 4.6 ± 3.0 mSv; P < 0.0001). Image noise (37.8 ± 1.4 HU vs 38.2 ± 2.4 HU; P = 0.20) and signal density (461.7 ± 51.9 HU vs 462.2 ± 51.2 HU; P = 0.54) levels did not differ between FBP and IR groups, respectively. The IR group was associated to significant effective dose reductions, irrespective of the acquisition mode.
CONCLUSION: Application of IR in CTCA preserves image interpretability despite a significant reduction in radiation dose.
Core tip: A consecutive series of 200 patients referred to our institution to undergo computer tomography coronary angiography (CTCA) were sequentially assigned to filtered back projection (FBP) or iterative reconstruction (IR). The percent assessable coronary segment was similar between groups. Radiation dose was significantly lower in the IR group. Image noise and signal density levels did not differ between FBP and IR groups. The IR group was associated to significant effective dose reductions, irrespective of the acquisition mode. Our findings suggest that application of IR in CTCA preserves image interpretability despite a significant reduction in radiation dose.