Davide Ippolito1,2, Davide Fior3,4, Cammillo Talei Franzesi3,4, Luca Riva3,4, Alessandra Casiraghi3,4, Sandro Sironi4,5. 1. Department of Diagnostic Radiology, "San Gerardo" Hospital, Via Pergolesi 33, 20900, Monza, MB, Italy. davide.atena@tiscalinet.it. 2. School of Medicine, University of Milano-Bicocca, Via Cadore 48, 20900, Monza, MB, Italy. davide.atena@tiscalinet.it. 3. Department of Diagnostic Radiology, "San Gerardo" Hospital, Via Pergolesi 33, 20900, Monza, MB, Italy. 4. School of Medicine, University of Milano-Bicocca, Via Cadore 48, 20900, Monza, MB, Italy. 5. Department of Diagnostic Radiology, "Papa Giovanni XXIII" Hospital, Bergamo, Italy.
Abstract
BACKGROUND: Effective radiation dose in coronary CT angiography (CTCA) for coronary artery bypass graft (CABG) evaluation is remarkably high because of long scan lengths. Prospective electrocardiographic gating with iterative reconstruction can reduce effective radiation dose. OBJECTIVES: To evaluate the diagnostic performance of low-kV CT angiography protocol with prospective ecg-gating technique and iterative reconstruction (IR) algorithm in follow-up of CABG patients compared with standard retrospective protocol. METHODS: Seventy-four non-obese patients with known coronary disease treated with artery bypass grafting were prospectively enrolled. All the patients underwent 256 MDCT (Brilliance iCT, Philips) CTCA using low-dose protocol (100 kV; 800 mAs; rotation time: 0.275 s) combined with prospective ECG-triggering acquisition and fourth-generation IR technique (iDose4; Philips); all the lengths of the bypass graft were included in the evaluation. A control group of 42 similar patients was evaluated with a standard retrospective ECG-gated CTCA (100 kV; 800 mAs).On both CT examinations, ROIs were placed to calculate standard deviation of pixel values and intra-vessel density. Diagnostic quality was also evaluated using a 4-point quality scale. RESULTS: Despite the statistically significant reduction of radiation dose evaluated with DLP (study group mean DLP: 274 mGy cm; control group mean DLP: 1224 mGy cm; P value < 0.001). No statistical differences were found between PGA group and RGH group regarding intra-vessel density absolute values and SNR. Qualitative analysis, evaluated by two radiologists in "double blind", did not reveal any significant difference in diagnostic quality of the two groups. CONCLUSIONS: The development of high-speed MDCT scans combined with modern IR allows an accurate evaluation of CABG with prospective ECG-gating protocols in a single breath hold, obtaining a significant reduction in radiation dose.
BACKGROUND: Effective radiation dose in coronary CT angiography (CTCA) for coronary artery bypass graft (CABG) evaluation is remarkably high because of long scan lengths. Prospective electrocardiographic gating with iterative reconstruction can reduce effective radiation dose. OBJECTIVES: To evaluate the diagnostic performance of low-kV CT angiography protocol with prospective ecg-gating technique and iterative reconstruction (IR) algorithm in follow-up of CABG patients compared with standard retrospective protocol. METHODS: Seventy-four non-obesepatients with known coronary disease treated with artery bypass grafting were prospectively enrolled. All the patients underwent 256 MDCT (Brilliance iCT, Philips) CTCA using low-dose protocol (100 kV; 800 mAs; rotation time: 0.275 s) combined with prospective ECG-triggering acquisition and fourth-generation IR technique (iDose4; Philips); all the lengths of the bypass graft were included in the evaluation. A control group of 42 similar patients was evaluated with a standard retrospective ECG-gated CTCA (100 kV; 800 mAs).On both CT examinations, ROIs were placed to calculate standard deviation of pixel values and intra-vessel density. Diagnostic quality was also evaluated using a 4-point quality scale. RESULTS: Despite the statistically significant reduction of radiation dose evaluated with DLP (study group mean DLP: 274 mGy cm; control group mean DLP: 1224 mGy cm; P value < 0.001). No statistical differences were found between PGA group and RGH group regarding intra-vessel density absolute values and SNR. Qualitative analysis, evaluated by two radiologists in "double blind", did not reveal any significant difference in diagnostic quality of the two groups. CONCLUSIONS: The development of high-speed MDCT scans combined with modern IR allows an accurate evaluation of CABG with prospective ECG-gating protocols in a single breath hold, obtaining a significant reduction in radiation dose.
Authors: J Levi Chazen; Martin R Prince; Rowena Yip; James K Min; Jonathan W Weinsaft; Claudia I Henschke; Matthew D Cham Journal: Acad Radiol Date: 2010-06-12 Impact factor: 3.173
Authors: James P Earls; Elise L Berman; Bruce A Urban; Charlene A Curry; Judith L Lane; Robert S Jennings; Colin C McCulloch; Jiang Hsieh; John H Londt Journal: Radiology Date: 2008-01-14 Impact factor: 11.105
Authors: Márcio Sommer Bittencourt; Bernhard Schmidt; Martin Seltmann; Gerd Muschiol; Dieter Ropers; Werner Günther Daniel; Stephan Achenbach Journal: Int J Cardiovasc Imaging Date: 2010-12-01 Impact factor: 2.357