BACKGROUND AND PURPOSE: Daily use of conventional electronic portal imaging devices (EPID) for organ tracking is limited due to the relatively high dose required for high quality image acquisition. We studied the use of a novel dose saving acquisition mode (RadMode) allowing to take images with one monitor unit per image in prostate cancer patients undergoing intensity-modulated radiotherapy (IMRT) and tracking of implanted fiducial gold markers. PATIENTS AND METHODS: Twenty five patients underwent implantation of three fiducial gold markers prior to the planning CT. Before each treatment of a course of 37 fractions, orthogonal localization images from the antero-posterior and from the lateral direction were acquired. Portal images of both the setup procedure and the five IMRT treatment beams were analyzed. RESULTS: On average, four localization images were needed for a correct patient setup, resulting in four monitor units extra dose per fraction. The mean extra dose delivered to the patient was thereby increased by 1.2%. The procedure was precise enough to reduce the mean displacements prior to treatment to < o =0.3 mm. CONCLUSIONS: The use of a new dose saving acquisition mode enables to perform daily EPID-based prostate tracking with a cumulative extra dose of below 1 Gy. This concept is efficiently used in IMRT-treated patients, where separation of setup beams from treatment beams is mandatory.
BACKGROUND AND PURPOSE: Daily use of conventional electronic portal imaging devices (EPID) for organ tracking is limited due to the relatively high dose required for high quality image acquisition. We studied the use of a novel dose saving acquisition mode (RadMode) allowing to take images with one monitor unit per image in prostate cancerpatients undergoing intensity-modulated radiotherapy (IMRT) and tracking of implanted fiducial gold markers. PATIENTS AND METHODS: Twenty five patients underwent implantation of three fiducial gold markers prior to the planning CT. Before each treatment of a course of 37 fractions, orthogonal localization images from the antero-posterior and from the lateral direction were acquired. Portal images of both the setup procedure and the five IMRT treatment beams were analyzed. RESULTS: On average, four localization images were needed for a correct patient setup, resulting in four monitor units extra dose per fraction. The mean extra dose delivered to the patient was thereby increased by 1.2%. The procedure was precise enough to reduce the mean displacements prior to treatment to < o =0.3 mm. CONCLUSIONS: The use of a new dose saving acquisition mode enables to perform daily EPID-based prostate tracking with a cumulative extra dose of below 1 Gy. This concept is efficiently used in IMRT-treated patients, where separation of setup beams from treatment beams is mandatory.
Authors: Arash O Naghavi; Tobin J Strom; Kevin Nethers; Alex A Cruz; Nicholas B Figura; Kushagra Shrinath; Binglin Yue; Jongphil Kim; Matthew C Biagioli; Daniel C Fernandez; Randy V Heysek; Richard B Wilder Journal: Int J Clin Oncol Date: 2014-09-06 Impact factor: 3.402
Authors: George Yang; Tobin J Strom; Richard B Wilder; Kushagra Shrinath; Eric A Mellon; Daniel C Fernandez; Matthew C Biagioli Journal: Int Braz J Urol Date: 2015 May-Jun Impact factor: 1.541
Authors: Pirus Ghadjar; Jacqueline Vock; Daniel Vetterli; Peter Manser; Roland Bigler; Jan Tille; Axel Madlung; Frank Behrensmeier; Roberto Mini; Daniel M Aebersold Journal: Radiat Oncol Date: 2008-10-20 Impact factor: 3.481
Authors: Christopher Nelson; Peter Balter; Rodolfo C Morice; Bum Choi; Rajat J Kudchadker; Kara Bucci; Joe Y Chang; Lei Dong; Susan Tucker; Sastry Vedam; Tina Briere; George Starkschall Journal: J Appl Clin Med Phys Date: 2008-10-30 Impact factor: 2.102