Relationships among magnetic resonance imaging, histological findings, and IGF-I in steroid-induced osteonecrosis of the femoral head in rabbits
Relationships among magnetic resonance imaging, histological findings, and IGF-I in steroid-induced osteonecrosis of the femoral head in rabbits作者机构：Division of Neurobiology and Physiology Institute of Neuroscience School of Medicine Zhejiang University Hangzhou 310058 China Department of Radiology the 117 Hospital of the Chinese People’s Liberation Army Hangzhou 310013 China
出 版 物：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 (浙江大学学报B辑(生物医学与生物技术)(英文版))
年 卷 期：2008年第9卷第9期
页 面：739-746页
核心收录：
学科分类：0831[工学-生物医学工程（可授工学、理学、医学学位）] 100207[医学-影像医学与核医学] 1002[医学-临床医学] 100210[医学-外科学(含：普外、骨外、泌尿外、胸心外、神外、整形、烧伤、野战外)] 08[工学] 1010[医学-医学技术（可授医学、理学学位）] 10[医学]
基 金：Project (No. 06MA169) supported by the Medical Science Founda-tion of Nanjing Military Region China
主 题：Dexamethasone (DEX) Insulin-like growth factor-I (IGF-I) Magnetic resonance imaging (MRI) Osteonecrosis of the femoral head Pathology
摘 要：Objective: To study the relationships among magnetic resonance imaging (MRI), histological findings, and insu- lin-like growth factor-I (IGF-I) in steroid-induced osteonecrosis of the femoral head in rabbits. Methods: Thirty rabbits were randomly divided into experimental Group A (n=15) and control Group B (n=15). The 7.5 mg/kg (2 ml) of dexamethasone (DEX) and physiological saline (2 ml) were injected into the right gluteus medius muscle twice at one-week intervals in animals of Groups A and B, respectively. At 4, 8 and 16 weeks after obtaining an MRI, the rabbits were sacrificed and the femoral head from one side was removed for histological study of lacunae empty of osteocytes, subchondral vessels, and size of fat cells under microscopy, and the femoral head from the other side was removed for enzyme-linked immunoadsorbent assay (ELISA) for IGF-I. Results: At 4, 8 and 16 weeks after treatment, no necrotic lesions were detected in Group B, while they were detected in Group A. Light microscopy revealed that the fat cells of the marrow cavity were enlarged, subchondral vessels were evidently decreased, and empty bone lacunae were clearly increased. The IGF-I levels in Group A were significantly higher than those in Group B. At 8 weeks after the DEX injection, the MRI of all 20 femora showed an inhomogeneous, low signal intensity area in the femoral head, and at 16 weeks, the findings of all 10 femora showed a specific line-like sign. The MRI findings of all femora in Group B were normal. Conclusion: MRI is a highly sensitive means of diagnosing early experimental osteonecrosis of the femoral head. However, the abnormal marrow tissues appeared later than 4 weeks when the expression of IGF-I increased. This reparative factor has an early and important role in response to steroid-induced osteonecrosis of the femoral head, and provides a theoretical foundation for understanding the pathology and designing new therapies.
同方期刊数据库