Houda Bahig1, Jacques de Guise2, Toni Vu3, Danis Blais4, Carl Chartrand-Lefebvre5, Nhu Tram Nguyen6, Sophie Lavertu3, Jean-Pierre Guay3, Stephane Bedwani3, David Roberge3. 1. Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada; Research Center, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. Electronic address: houda.bahig.chum@ssss.gouv.qc.ca. 2. Research Center, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. 3. Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada; Research Center, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. 4. Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. 5. Research Center, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada; Department of Radiology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. 6. Department of Radiation Oncology, Juravinski Hospital and Cancer Centre, Hamilton, Ontario, Canada.
Abstract
PURPOSE: To assess radiation dose variation to the left anterior descending artery (LAD), left main coronary artery (LMCA), left ventricle (LV), and whole heart (WH) during the cardiac cycle using dual source computed tomography (DSCT). METHODS AND MATERIALS: The present prospective study included patients with left-side breast cancer planned to undergo tangential radiation therapy. An electrocardiogram-synchronized contrast-injected DSCT scan was obtained with the patient in the treatment position, in deep-inspiration breath-hold, using retrospective sequential acquisition. The WH, LV, LMCA, and proximal, middle, and distal LAD segments were contoured on each phase of the cardiac cycle. The maximum, minimum, and mean Hausdorff distance between each structure and the tangential fields was assessed in ventricular systole and diastole. Four-dimensional dose-volume histograms were used to compare the systolic and diastolic dosimetric data. RESULTS: Ten patients were enrolled. The average maximum, minimum, and mean Hausdorff distance variation from systole to diastole was ≤4 mm for the LV and LMCA and ≤3 mm for the WH and LAD segments. WH maximum dose and volume receiving 5 Gy were decreased in systole compared with diastole (42.9 Gy versus 44.5 Gy, P = .03, and 21.7 cm3 versus 27.7 cm3, P = .01), but the mean dose remained similar throughout the cycle. The maximum and mean dose to the distal LAD was 21.2 Gy versus 26.6 Gy (P = .005) and 8.6 Gy versus 13.2 Gy (P = .006) in systole versus diastole, respectively. The maximum and mean dose to the middle LAD was 18.4 Gy versus 25.1 Gy (P = .005) and 8.5 Gy versus 10.2 Gy in systole versus diastole (P = .005). The maximum dose to the LV was lower in systole than in diastole (21.5 Gy vs 26.7 Gy; P = .005). CONCLUSIONS: In addition to deep-inspiration breath-hold, systolic irradiation is associated with a reduction in dose to the LAD, LV, and WH. In addition to its potential use in radiation planning for cardiac gating, DSCT imaging can be used to help define a planning organ at risk volume for clinically important cardiac substructures. Crown
PURPOSE: To assess radiation dose variation to the left anterior descending artery (LAD), left main coronary artery (LMCA), left ventricle (LV), and whole heart (WH) during the cardiac cycle using dual source computed tomography (DSCT). METHODS AND MATERIALS: The present prospective study included patients with left-side breast cancer planned to undergo tangential radiation therapy. An electrocardiogram-synchronized contrast-injected DSCT scan was obtained with the patient in the treatment position, in deep-inspiration breath-hold, using retrospective sequential acquisition. The WH, LV, LMCA, and proximal, middle, and distal LAD segments were contoured on each phase of the cardiac cycle. The maximum, minimum, and mean Hausdorff distance between each structure and the tangential fields was assessed in ventricular systole and diastole. Four-dimensional dose-volume histograms were used to compare the systolic and diastolic dosimetric data. RESULTS: Ten patients were enrolled. The average maximum, minimum, and mean Hausdorff distance variation from systole to diastole was ≤4 mm for the LV and LMCA and ≤3 mm for the WH and LAD segments. WH maximum dose and volume receiving 5 Gy were decreased in systole compared with diastole (42.9 Gy versus 44.5 Gy, P = .03, and 21.7 cm3 versus 27.7 cm3, P = .01), but the mean dose remained similar throughout the cycle. The maximum and mean dose to the distal LAD was 21.2 Gy versus 26.6 Gy (P = .005) and 8.6 Gy versus 13.2 Gy (P = .006) in systole versus diastole, respectively. The maximum and mean dose to the middle LAD was 18.4 Gy versus 25.1 Gy (P = .005) and 8.5 Gy versus 10.2 Gy in systole versus diastole (P = .005). The maximum dose to the LV was lower in systole than in diastole (21.5 Gy vs 26.7 Gy; P = .005). CONCLUSIONS: In addition to deep-inspiration breath-hold, systolic irradiation is associated with a reduction in dose to the LAD, LV, and WH. In addition to its potential use in radiation planning for cardiac gating, DSCT imaging can be used to help define a planning organ at risk volume for clinically important cardiac substructures. Crown
Authors: Frances K Duane; Naomi B Boekel; Judy N Jacobse; Zhe Wang; Berthe M P Aleman; Sarah C Darby; Michael Schaapveld; Flora E van Leeuwen; Margreet H A Baaijens; Samantha Warren; Carolyn W Taylor Journal: Clin Transl Radiat Oncol Date: 2022-07-16
Authors: Kekoa Taparra; Scott C Lester; W Scott Harmsen; Molly Petersen; Ryan K Funk; Miran J Blanchard; Phillip Young; Joerg Herrmann; Ashley Hunzeker; Heather Schultz; Cynthia McCollough; Alexandria Tasson; Shuai Leng; James A Martenson; Thomas J Whitaker; Eric Williamson; Nadia N Laack Journal: Int J Part Ther Date: 2020-09-04
Authors: Frances K Duane; Paul McGale; Dorthe Brønnum; David J Cutter; Sarah C Darby; Marianne Ewertz; Sara Hackett; Per Hall; Ebbe L Lorenzen; Kazem Rahimi; Zhe Wang; Samantha Warren; Carolyn W Taylor Journal: Pract Radiat Oncol Date: 2019-01-26