OBJECTIVES: To compare the effects of different irradiators on the establishment of osteoradionecrosis of jaw model (ORNJ) to explore an ideal modeling method. METHODS: A total of 33 adult SD rats were included and randomly divided into three groups according to the radiation equipment, namely, the blank control (CN, 3 rats), group A (linear accelerator irradiation, 15 rats), and group B (small-animal irradiator irradiation, 15 rats). Groups A and B were irradiated with daily fractions of 7, 8, and 9 Gy for 5 days and further divided into three subgroups as follows: group A RESULTS: At 3 weeks after dental extractions, complete gingival healing was found in the regions of dental extractions in groups A CONCLUSIONS Small-animal irradiator irradiation is an ideal device for establishing ORNJ model.
Animals ; Mandible ; Molar ; Osteoradionecrosis/etiology* ; Rats ; Rats, Sprague-Dawley ; X-Ray Microtomography

Nasopharyngeal cancer (NPC) is a common malignancy affecting Asian countries, especially the Chinese population. Treatment regimes and results have improved over the years with better overall survival outcome data. Radiotherapy with or without chemotherapy is successful in many patients. Local recurrences are treated with nasopharyngectomy or another course of radiotherapy. The upper cervical spine and skull base can also be involved in NPC patients. Possible aetiologies are osteoradionecrosis, chronic infection and tumour invasion. This article reviews the NPC involvement of C1-2 due to the various pathologies as well as the diagnostic and surgical treatment strategies. Three clinical cases that were surgically treated are discussed along with a review of the current literature.
Adult ; Aged ; Bone Neoplasms ; secondary ; Carcinoma ; Cervical Vertebrae ; drug effects ; radiation effects ; China ; Female ; Humans ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; diagnosis ; surgery ; Osteomyelitis ; diagnosis ; etiology ; surgery ; Osteoradionecrosis ; etiology ; Recurrence ; Spinal Fractures ; etiology ; Treatment Outcome

Postradiation nasopharyngeal necrosis is an important late effect of radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma. In the present study, we reviewed the clinical and imaging features of 67 patients with pathologically diagnosed postradiation nasopharyngeal necrosis who were treated at Sun Yat-sen University Cancer Center between June 2006 and January 2010. Their clinical manifestations, endoscopic findings, and imaging features were analyzed. Early nasopharyngeal necrosis was limited to a local site in the nasopharyngeal region, and the tissue defect was not obvious, whereas deep parapharyngeal ulcer or signs of osteoradionecrosis in the basilar region was observed in serious cases. Those with osteoradionecrosis and/or exposed carotid artery had a high mortality. In conclusion, Postradiation nasopharyngeal necrosis has characteristic magnetic resonance imaging appearances, which associate well with clinical findings, but pathologic examination is essential to make the diagnosis.
Adult ; Aged ; Carcinoma ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; radiotherapy ; Nasopharynx ; pathology ; radiation effects ; Necrosis ; Osteoradionecrosis ; diagnosis ; etiology ; Radiation Injuries ; diagnosis ; etiology ; Radiotherapy, Intensity-Modulated ; adverse effects