title: A preliminary investigation into the effects of X-ray radiation on superficial cranial vascularization.
abstract: Radiation therapy (RT) is an established treatment modality for malignant neoplasms. RT induces tissue damage that may lead to osteoradionecrosis in more severe cases. Suitable animal models to study RT-induced changes in membranous craniofacial bone are currently not available. The aim of this study was therefore to quantify RT-induced changes in cranial microcirculation using a newly developed calvaria chamber model and to relate these changes to RT-induced histological damage. New Zealand white rabbits received a total radiation dose of 18.75 Gy through the calvaria chamber, and the number of vessels, the vessel length density (VLD), and angiogenic sprouting were quantified on a weekly basis during a 12-week period. At the end of 12 weeks, the RT-treated (n = 5) or control (n = 5) calvarias were biopsied for histopathological analysis. RT resulted in a steep reduction in the number of vessels and the VLD during the first 3 weeks, particularly in larger-diameter vessels, followed by a flat stabilization/remodeling phase in the subsequent 9 weeks that never restored to baseline values. Histomorphometric analysis revealed a high degree of osteocytic depletion, prominent hypocellularity in the lacunae and intraosseous vasculature, enlarged and nonconcentric Haversian systems, and a severely disorganized bone matrix in the RT-treated calvarias. Despite the prevalence of some angiogenic potential, the RT-induced effects in the early phase persisted in the intermediate to late phase, which may have contributed to the poor recovery of the RT-treated bone.
authors.affiliation: School of Dentistry, Lille University Hospital, IFR, IMPRT, Lille, France. desmons@lille.inserm.fr
authors.forename: Sophie
authors.initials: S
authors.lastname: Desmons
authors.forename: Michal
authors.initials: M
authors.lastname: Heger
authors.forename: Caroline
authors.initials: C
authors.lastname: Delfosse
authors.forename: Guillaume
authors.initials: G
authors.lastname: Falgayrac
authors.forename: Thierry
authors.initials: T
authors.lastname: Sarrazin
authors.forename: Claire
authors.initials: C
authors.lastname: Delattre
authors.forename: Sylvain
authors.initials: S
authors.lastname: Catros
authors.forename: Serge
authors.initials: S
authors.lastname: Mordon
authors.forename: Guillaume
authors.initials: G
authors.lastname: Penel
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000473:pathology / Q000503:physiopathology / Q000528:radiation effects; D001861:Bone Regeneration / Q000502:physiology / Q000528:radiation effects*; D004195:Disease Models, Animal; D005260:Female; D019044:Image Cytometry; D008833:Microcirculation / Q000502:physiology / Q000528:radiation effects*; D018919:Neovascularization, Physiologic / Q000502:physiology / Q000528:radiation effects*; D010025:Osteoradionecrosis / Q000473:pathology* / Q000503:physiopathology; D011817:Rabbits; D011829:Radiation Dosage; D020127:Recovery of Function / Q000502:physiology / Q000528:radiation effects; D012886:Skull / Q000098:blood supply* / Q000503:physiopathology / Q000528:radiation effects*; D014965:X-Rays / Q000009:adverse effects