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:...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.展开更多
Objective： To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis （AVN） of the femoral head by single photon emission computerized tomography and computerized tomography （SPECT/CT）...Objective： To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis （AVN） of the femoral head by single photon emission computerized tomography and computerized tomography （SPECT/CT）. Methods： Totally 18 adult beagle dogs were divided randomly into three equal-sized （n=6） groups. Subsequently different degrees of ischemia model were developed by de- stroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tis- sues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/ CT was performed. Laser Doppler Flowmetry （LDF） measurements were also obtained at three different time points （before operation, immediately and three hours after operation） in order to assess the change process of blood supply to the femoral head. Results： SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femo- ral heads in Group A （t=-0.09,P=-0.94） and Group B （t= 0.52, P=0.62）. However, in Group C, it was 261±62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from （45.0±3.3） PU to （39.1±3.7） PU in Group A, from （44.0±2.7） PU to （34.3±2.6） PU in Group B, and from （47.3±2.1） PU to （4.96±0.6） PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C. Conclusion： SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.展开更多
目的:探讨早期成人股骨头缺血坏死(femoral head necrosis,FHN)的MR、CT、SPECT和X线平片4种影像学检查的成本效益比,寻找较好的成本效益的检查方法。方法:分析和总结82例129髋随访和病理证实或具有典型影像学表现的早期(ARCO I^II期)成...目的:探讨早期成人股骨头缺血坏死(femoral head necrosis,FHN)的MR、CT、SPECT和X线平片4种影像学检查的成本效益比,寻找较好的成本效益的检查方法。方法:分析和总结82例129髋随访和病理证实或具有典型影像学表现的早期(ARCO I^II期)成人FHN病人的髋关节影像学资料。全部病例均同期行MRI、CT、单光子发射计算机体层摄影(single photon emission computed tomography,SPECT)和X线平片检查。采用成本效果分析法(cost-effectiveness analysis,CE A),对4种影像学检查诊断效率研究中的数据进行分析,比较其正确检出费用(cost of accurate diagnosis,CAD)。结果:4种影像学检查方法的诊断差异有显著性意义。早期诊断成人FHN的检出费用最低的是X线平片,对于X线平片确诊组和诊断可疑组,MRI检出费用并无太大变化,而CT费用最低;对于X线平片诊断阴性组,MRI诊断的敏感性和准确性综合比较高于CT和SPECT,且诊断费用也最低。结论:X线适合早期股骨头坏死的筛选,而MRI诊断的敏感性和准确性综合比较高于CT和SPECT,而且应当作为X线诊断阴性的可疑股骨头坏死患者进一步诊断的首选。。展开更多
基金Project (No. 06MA169) supported by the Medical Science Founda-tion of Nanjing Military Region, China
文摘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.
文摘Objective： To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis （AVN） of the femoral head by single photon emission computerized tomography and computerized tomography （SPECT/CT）. Methods： Totally 18 adult beagle dogs were divided randomly into three equal-sized （n=6） groups. Subsequently different degrees of ischemia model were developed by de- stroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tis- sues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/ CT was performed. Laser Doppler Flowmetry （LDF） measurements were also obtained at three different time points （before operation, immediately and three hours after operation） in order to assess the change process of blood supply to the femoral head. Results： SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femo- ral heads in Group A （t=-0.09,P=-0.94） and Group B （t= 0.52, P=0.62）. However, in Group C, it was 261±62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from （45.0±3.3） PU to （39.1±3.7） PU in Group A, from （44.0±2.7） PU to （34.3±2.6） PU in Group B, and from （47.3±2.1） PU to （4.96±0.6） PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C. Conclusion： SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.
文摘目的:探讨早期成人股骨头缺血坏死(femoral head necrosis,FHN)的MR、CT、SPECT和X线平片4种影像学检查的成本效益比,寻找较好的成本效益的检查方法。方法:分析和总结82例129髋随访和病理证实或具有典型影像学表现的早期(ARCO I^II期)成人FHN病人的髋关节影像学资料。全部病例均同期行MRI、CT、单光子发射计算机体层摄影(single photon emission computed tomography,SPECT)和X线平片检查。采用成本效果分析法(cost-effectiveness analysis,CE A),对4种影像学检查诊断效率研究中的数据进行分析,比较其正确检出费用(cost of accurate diagnosis,CAD)。结果:4种影像学检查方法的诊断差异有显著性意义。早期诊断成人FHN的检出费用最低的是X线平片,对于X线平片确诊组和诊断可疑组,MRI检出费用并无太大变化,而CT费用最低;对于X线平片诊断阴性组,MRI诊断的敏感性和准确性综合比较高于CT和SPECT,且诊断费用也最低。结论:X线适合早期股骨头坏死的筛选,而MRI诊断的敏感性和准确性综合比较高于CT和SPECT,而且应当作为X线诊断阴性的可疑股骨头坏死患者进一步诊断的首选。。
