caa a22 4500 605520453 CHVBK 20210128100735.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00223-015-0010-9 doi (NATIONALLICENCE)springer-10.1007/s00223-015-0010-9 Micro-CT Analysis of Radiation-Induced Osteopenia and Bone Hypovascularization in Rat [Elektronische Daten] [Guillaume Michel, Pauline Blery, Paul Pilet, Jérôme Guicheux, Pierre Weiss, Olivier Malard, Florent Espitalier] Treatment of carcinomas of the upper aerodigestive tract often requires external radiation therapy. However, radiation affects all the components of bone, with different degrees of sensitivity, and may produce severe side effects such as mandibular osteoradionecrosis (ORN). Intraosseous vascularization is thought to be decreased after irradiation, but its impact on total bone volume is still controversial. The aim of this study was to compare intraosseous vascularization, cortical bone thickness, and total bone volume in a rat model of ORN versus nonirradiated rats, using a micro-computed tomography (micro-CT) analysis after intracardiac injection of a contrast agent. The study was performed on 8-week-old Lewis 1A rats (n=14). Eleven rats underwent external irradiation on the hind limbs by a single 80-Gy dose. Three rats did not receive irradiation and served as controls for statistical analysis. Eight weeks after the external irradiation, all the animals received a barium sulfate intracardiac injection under general anesthesia. All samples were analyzed with the micro-computed tomography system at a resolution of 5.5μm. The images were later processed to create 3D reconstructions and study vascularization, bone volume, and cortical thickness. Data from irradiated and nonirradiated rats were compared using the Kruskal-Wallis test. No animal died after irradiation. Nineteen irradiated tibias and six nonirradiated tibias were included for micro-CT analysis. The vessel percentage was significantly lower in irradiated bones (p=0.0001). The distance between the vessels, a marker of vascular destruction, was higher after irradiation (p=0.001). The vessels were also more altered distally after irradiation (p=0.028). Cortical thickness was severely decreased after irradiation, sometimes even reduced to zero. Both trabecular and cortical structures were destroyed after irradiation, with wide bone gaps. Finally, both total bone volume (p=0.0001) and cortical thickness (p=0.0001) were significantly decreased in irradiated tibias compared to nonirradiated tibias. These results led to multiple spontaneous fractures in the irradiated group, and the destruction of intraosseous vessels observed macroscopically with the radiographic preview. This study revealed the impact of radiation on intraosseous vasculature and cortical bone with a micro-CT analysis in a rat ORN model. Hypovascularization and osteopenia are consistent with the literature, contributing a morphological scale with high resolution. Visualization of the vasculature by micro-CT is an innovative technique to see the changes after radiation, and should help adjust bone tissue engineering in irradiated bone. Springer Science+Business Media New York, 2015 X-ray micro-tomography nationallicence Radiotherapy nationallicence Bone tissue nationallicence Blood supply nationallicence Michel Guillaume Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut Blery Pauline Service d'Odontologie Restauratrice et Chirurgicale, Centre Hospitalier Universitaire de Nantes, Nantes, France aut Pilet Paul INSERM, UMRS 791, LIOAD, Université de Nantes, Nantes, France aut Guicheux Jérôme INSERM, UMRS 791, LIOAD, Université de Nantes, Nantes, France aut Weiss Pierre Service d'Odontologie Restauratrice et Chirurgicale, Centre Hospitalier Universitaire de Nantes, Nantes, France aut Malard Olivier Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut Espitalier Florent Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut Calcified Tissue International Springer US; http://www.springer-ny.com 97/1(2015-07-01), 62-68 0171-967X 97:1<62 2015 97 223 https://doi.org/10.1007/s00223-015-0010-9 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00223-015-0010-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Michel Guillaume Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut NATIONALLICENCE 700 1- Blery Pauline Service d'Odontologie Restauratrice et Chirurgicale, Centre Hospitalier Universitaire de Nantes, Nantes, France aut NATIONALLICENCE 700 1- Pilet Paul INSERM, UMRS 791, LIOAD, Université de Nantes, Nantes, France aut NATIONALLICENCE 700 1- Guicheux Jérôme INSERM, UMRS 791, LIOAD, Université de Nantes, Nantes, France aut NATIONALLICENCE 700 1- Weiss Pierre Service d'Odontologie Restauratrice et Chirurgicale, Centre Hospitalier Universitaire de Nantes, Nantes, France aut NATIONALLICENCE 700 1- Malard Olivier Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut NATIONALLICENCE 700 1- Espitalier Florent Service d'O.R.L. et de chirurgie cervico-faciale, Centre Hospitalier Universitaire de Nantes, CHU Hôtel Dieu, 1, Place A. Ricordeau, BP 1005, 44093, Nantes Cedex 01, France aut NATIONALLICENCE 773 0- Calcified Tissue International Springer US; http://www.springer-ny.com 97/1(2015-07-01), 62-68 0171-967X 97:1<62 2015 97 223