MR弥散成像联合骨生化和病理对兔超早期激素性股骨头坏死的研究

发布时间：2018-08-26 12:41

【摘要】：目的：采用弥散加权磁共振成像（diffusion weighted magnetic resonance imaging,DWI）技术联合骨生化与病理组织学检查对兔超早期激素性股骨头坏死（osteonecrosis offemoral head,ONFH）模型进行研究，进一步探讨DWI对超早期激素性ONFH的诊断价值。方法：将40只健康成年中国大耳白兔随机分为对照组和实验组，每组20只。ONFH造模：实验组兔经耳缘静脉首次注射马血清10ml/kg一次，间隔2周后再次注入马血清5ml/kg，Qd，连续2天；于首次注射马血清后，间隔24小时肌肉注射甲基强的松龙4mg/kg，每周注射一次共8周；对照组在相同时间点用同样的方法注射等量的生理盐水。对照组和实验组分别于注射甲基强的松龙后2、4、6、8周周末各随机5只兔行下列检查：先抽耳缘静脉血化验抗酒石酸酸性磷酸酶（tartrate-resistant acidphosphatase5b，，TRACP-5b）、骨钙素（bone gla protein，BGP）；再行常规MRI及DWI检查，获得股骨头负重区表观弥散系数（apparent diffusion coefficient,ADC值）；最后处死动物取双侧股骨头标本进行病理组织学检查。结果：骨生化结果：与对照组比较：实验组4、6、8周TRACP-5b明显升高、BGP明显降低（P＜0.05），实验组2周TRACP-5b、BGP未见明显变化（P＞0.05）；与实验组2周比较：实验组4、6、8周TRACP-5b明显升高、BGP明显降低（P＜0.05）；与实验组4周比较：实验组8周TRACP-5b明显升高、BGP明显降低（P＜0.05），实验组6周TRACP-5b、BGP未见明显变化（P＞0.05）；与实验组6周比较:实验组8周TRACP-5b明显升高、BGP明显降低（P＜0.05）；对照组各时间点TRACP-5b、BGP值未见明显变化（P＞0.05）；MRI结果：实验组和对照组各时间点常规MRI和DWI均未显示异常；各时间点实验组ADC值明显高于对照组；随着时间点的延长，实验组ADC值逐渐升高（P＜0.05）。病理结果：对照组2-8周切片均显示软骨细胞排列整齐，骨小梁完整、排列规则，骨细胞清晰，骨小梁周围见成串排列的成骨细胞，可见散在的空骨陷窝，骨髓腔内造血细胞丰富，脂肪细胞数量相对较少，大小均匀，形态正常；实验组2周时出现核边聚，空骨陷窝较对照组增多；4周时表现为骨小梁萎缩、变细、排列紊乱，周围成骨细胞数量明显减少，空骨陷窝数增加明显，脂肪细胞体积增大，部分融合；6-8周时可见骨小梁数量减少、粗大并断裂，未见深染的骨细胞核，核周空晕变大，见大量空骨陷窝，骨小梁周围见少量成骨细胞，骨髓区被增大的脂肪细胞所占据，部分融合。结论：1.马血清联合少量激素制作的ONFH模型适用于激素性ONFH超早期研究； 2.TRACP-5b、BGP检测对激素性ONFH超早期诊断具有参考价值；3.ADC值升高可反映超早期激素性ONFH的发生及发展，为临床提供有价值的无创诊断信息。
[Abstract]:Objective: to study the ultraearly steroid-induced femoral head necrosis (osteonecrosis offemoral head,ONFH) model in rabbits with diffusion weighted magnetic resonance imaging (diffusion weighted magnetic resonance imaging,DWI) technique combined with bone biochemistry and histopathology, and to explore the value of DWI in the diagnosis of hyper-early steroid-induced ONFH. Methods: forty healthy adult Chinese white rabbits were randomly divided into control group and experimental group. Each group (n = 20) was treated with ONFH. The rabbits in the experimental group were injected with horse serum 10ml/kg via the auricular vein for the first time. After 2 weeks' interval, the serum of the horse was injected again with 5 ml / kg QD for 2 days. After the first injection of horse serum, 4 mg / kg methylprednisolone was injected intramuscularly every 24 hours, once a week for 8 weeks, and the control group was injected with the same amount of normal saline at the same time. Two weeks after injection of methylprednisolone, the control group and the experimental group were randomly divided into 5 rabbits at the end of 8 weeks. The following examinations were performed: first, the venous blood samples were drawn from the ear margin for tartrate-resistant acid phosphatase (tartrate-resistant acidphosphatase5b,TRACP-5b), osteocalcin (bone gla protein,BGP, and then routine MRI and DWI were performed. The apparent diffusion coefficient (apparent diffusion coefficient,ADC) of the femoral head was obtained. Finally, the specimens of bilateral femoral head were taken for histopathological examination. Results: compared with the control group, the TRACP-5b of the experimental group increased significantly at the 8th week (P < 0. 05), but the TRACP-5b,BGP of the experimental group did not change significantly at 2 weeks (P > 0. 05). Compared with the experimental group (2 weeks), the TRACP-5b of the experimental group increased significantly at the 8th week (P < 0. 05), the TRACP-5b of the experimental group significantly increased at the 8th week (P < 0. 05), and the TRACP-5b,BGP of the experimental group was not changed at the 6th week (P > 0. 05). Compared with the experimental group at 6 weeks, the TRACP-5b of the experimental group increased significantly at the 8th week (P < 0. 05), the TRACP-5b,BGP value of the control group did not change significantly at each time point (P > 0. 05). The results showed that the routine MRI and DWI were not abnormal at each time point in the experimental group and the control group. The ADC value of the experimental group was significantly higher than that of the control group at each time point, and with the extension of the time point, the ADC value of the experimental group gradually increased (P < 0. 05). Pathological results: in the control group, chondrocytes were arranged neatly, bone trabeculae were intact, bone cells were clear, bone trabeculae were arranged in a string of osteoblasts, and scattered empty bone lacunae were observed in the control group at 2-8 weeks. The hematopoietic cells in the medullary cavity were abundant, the number of adipocytes was relatively small, the size of adipocytes was uniform, and the morphology was normal. The number of osteoblasts decreased significantly, the number of empty bone lacunae increased significantly, and the volume of adipocytes increased. At 6-8 weeks after partial fusion, the number of bone trabeculae decreased, the bone trabeculae were coarse and broken, and the nucleus of bone without deep staining became larger. A large number of empty bone lacunae, a small number of osteoblasts around the trabecular bone, bone marrow area occupied by enlarged adipocytes, partial fusion. Conclusion 1. The ONFH model made by equine serum combined with a small amount of hormones is suitable for the study of hormone ONFH ultraearly. 2. The detection of TRACP-5 BGP has a reference value for the diagnosis of hormone ONFH. 3. The increase of ADC value can reflect the occurrence and development of hormone ONFH in the very early stage. To provide valuable non-invasive diagnostic information for clinical.
【学位授予单位】：遵义医学院
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R681.8;R445.2

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