低场强MR对股骨头缺血坏死不同病理阶段MRI特点分析与临床分期诊断研究

目的：研究低场强环境下ANFH不同病理阶段的NRI特点，明确临床的早、中、晚期诊断。方法：参考有关资料对ANFH的NRI诊断要点结合临床症状、病史、有关检查、病理或髓芯针活检结果，划分出早、中、晚期的诊断标准。结果：其中21例病变形态为线条形、点片形或新月形，股骨头外形正常，关节间隙正常示早期，占12．43％；38例病变形态为环形、圆形或斑块形，股骨头轻度变扁，塌陷示为中期，占22．48％；有110例病变形态为扩展形、骨折形，股骨头明显变偏、塌陷及关节间隙变窄或骨折，示为晚期，占65．09％。结论：低场强NRI对ANFH不同病理阶段的病理变化的信号反应是灵敏的，图像显示满意、可信的，能为临床诊治提供积极的指导作用。

The diagnostic study of low field MRI towards the different pathologic stages of avascular necrosis of femoral head

Objective:To study the different signal of relevant pathologic stage,to confirm the diagnosis of clinical stages.Methods:Combining clinical symptom and relevant examining with the results of pathology or marrow needle biopsy,To analysis the signal traits of 169 AVN patients,to get the diagnosis criterion of different clinical stages.Results:The early stage of 21 patients show linear spot or lunular changes,the shape of the heads of femur and the joint space are normal.The metaphase of 38 patients show annular roundness and macular changes,the shape of the heads of femur is flat and collapsed slightly.The 110 patients show expansile and catagmatic changes,the head of each stage are quite different.Conclusion:With low field MRI avascular necrosis of femoral head diagnosis is sensitive credible and satisfactory,which can perform a valuable information for clinical diagnosis and theraphy.