【摘要】 目的 :研究早期股骨头无菌性坏死 (ANFH)的CT、MRI诊断价值。材料和方法 :健康成年中国白兔 3 0只 ,随机分成两组。实验组 2 4只 ,每周两次肌注地塞米松磷酸钠 7.5mg·kg-1诱发股骨头坏死模型。在第 3、6、9周采用中场MR及螺旋CT扫描行影像学分期。参照分期处死动物对股骨头标本行病理检查 ,评价影像诊断的准确性。结果 :送检的 0、Ⅰ、Ⅱ期各 12髋股骨头病理证实均存在早期骨坏死表现。中场MRI(T1WI)表现为不同程度局限性低信号改变。相应螺旋CT扫描依次为阴性 ,可疑 ,明确骨质疏松或硬化表现。结论 :中场MR结合螺旋CT扫描既可发现早期病变 ,又可进行分期 ,是研究早期ANFH的可靠手段。更多还原

【Abstract】 Purpose: To study the diagnostic value of CT and MRI in the early aseptic necrosis of the femoral head(ANFH). Materials and Methods: Thirty adult rabbits were divided into two groups. The animal model of ANFH was established by intra muscular injection of sodium phosphate dexamethasone at a dose of 7.5mg/kg in 24 rabbits two times a week. The staging and imaging findings of the early ANFH were determined by using middle field MRI and spiral CT(SCT) scan at the 3th,6th and 9th week. Rabbits were killed according to the staging and histopathologic examination of the femoral heads was performed for evaluating the accuracy of imaging diagnosis. Results: Early osteonecrosis were revealed in pathological examination of each 12 hips included imaging stage was stage 0、Ⅰ、Ⅱ. ANFH displayed different degrees of low signal intensity on T1WI in hips of Stage 0、Ⅰ、Ⅱand showed correspondingly negative, suspicious, osteoporosis or obvious of osteosclerosis on SCT scan. Conclusion: Middle field MRI combining with SCT scan could not only exactly display early ANFH, but show staging,it might be a reliable methods for the study of early ANFH.更多还原