PURPOSE: To investigate the underlying biology associated with stereotactic body radiotherapy (SBRT), both in vivo models and image-guided, highly focal irradiation systems are necessary. Here, we describe such an irradiation system and use it to examine normal tissue toxicity in a small-animal model at lung volumes similar to those associated with human therapy. METHODS AND MATERIALS: High-dose radiation was delivered to a small volume of the left lung of C3H/HeJCr mice using a small-animal stereotactic irradiator. The irradiator has a collimation mechanism to produce focal radiation beams, an imaging subsystem consisting of a fluorescent screen coupled to a charge-coupled device camera, and a manual positioning stage. Histopathologic examination and micro-CT were used to evaluate the radiation response. RESULTS: Focal obliteration of the alveoli by fibrous connective tissue, hyperplasia of the bronchiolar epithelium, and presence of a small number of inflammatory cells are the main reactions to low-volume/high-dose irradiation of the mouse lung. The tissue response suggested a radiation dose threshold for early phase fibrosis lying between 40 and 100 Gy. The irradiation system satisfied our requirements of high-dose-rate, small beam diameter, and precise localization and verification. CONCLUSIONS: We have established an experimental model and image-guided animal irradiation system for the study of high dose per fraction irradiations such as those used with SBRT at volumes analogous to those used in human beings. It will also allow the targeting of specific anatomical structures of the thorax or ultimately, orthotopic tumors of the lung. (c) 2010 Elsevier Inc. All rights reserved.
PURPOSE: To investigate the underlying biology associated with stereotactic body radiotherapy (SBRT), both in vivo models and image-guided, highly focal irradiation systems are necessary. Here, we describe such an irradiation system and use it to examine normal tissue toxicity in a small-animal model at lung volumes similar to those associated with human therapy. METHODS AND MATERIALS: High-dose radiation was delivered to a small volume of the left lung of C3H/HeJCr mice using a small-animal stereotactic irradiator. The irradiator has a collimation mechanism to produce focal radiation beams, an imaging subsystem consisting of a fluorescent screen coupled to a charge-coupled device camera, and a manual positioning stage. Histopathologic examination and micro-CT were used to evaluate the radiation response. RESULTS: Focal obliteration of the alveoli by fibrous connective tissue, hyperplasia of the bronchiolar epithelium, and presence of a small number of inflammatory cells are the main reactions to low-volume/high-dose irradiation of the mouse lung. The tissue response suggested a radiation dose threshold for early phase fibrosis lying between 40 and 100 Gy. The irradiation system satisfied our requirements of high-dose-rate, small beam diameter, and precise localization and verification. CONCLUSIONS: We have established an experimental model and image-guided animal irradiation system for the study of high dose per fraction irradiations such as those used with SBRT at volumes analogous to those used in human beings. It will also allow the targeting of specific anatomical structures of the thorax or ultimately, orthotopic tumors of the lung. (c) 2010 Elsevier Inc. All rights reserved.
Authors: Steven Eric Finkelstein; Robert Timmerman; William H McBride; Dörthe Schaue; Sarah E Hoffe; Constantine A Mantz; George D Wilson Journal: Clin Dev Immunol Date: 2011-11-15
Authors: Lucas H Rifkin; Strahinja Stojadinovic; Collin H Stewart; Kwang H Song; Michael C Maxted; Marcus H Bell; Natalie S Kashefi; Michael P Speiser; Michel Saint-Cyr; Michael D Story; Rod J Rohrich; Spencer A Brown; Timothy D Solberg Journal: Radiat Oncol Date: 2012-05-08 Impact factor: 3.481
Authors: Zhen-Yu Hong; Sung Ho Eun; Kwangwoo Park; Won Hoon Choi; Jung Il Lee; Eun-Jung Lee; Ji Min Lee; Michael D Story; Jaeho Cho Journal: J Radiat Res Date: 2014-02-20 Impact factor: 2.724