股骨头缺血坏死的分期与早期影像学诊断

Grading of avascular necrosis of the femoral head and early imaging diagnosis

目的 研究股骨头缺血坏死 (ANFH)的分期、早期影像学表现及诊断价值。方法 6 2例双侧股骨头行X线、CT及低场MRI检查 ,并对其影像学改变进行分期及等级稚和H检验和敏感性对照。结果 全部患者X线平片均诊断为早期ANFH ,共 91个部位。其中Ⅰ期 46个 ,表现为骨疏松及骨硬化 ;Ⅱ期 45个 ,为骨硬化和囊状透亮区。CT发现 5 6例早期ANFH ,共 86个部位。其中Ⅰ期34个 ,表现为星芒结构变形、骨疏松和骨硬化 ;Ⅱ期 30个 ,呈骨硬化及囊状透亮区 ;Ⅲ期 2 2个 ,以“新月征”为特征。低场MRI仅发现 44例 (73个部位 ) ,Ⅰ期 30个 ,为斑点状T1WI低或高信号 ;Ⅱ期2 3个 ,为T1WI及长TE梯度回波 (GRL)序列不规则形低、等、高信号 ;Ⅲ期 2 0个 ,在T1WI及GRL序列呈片状低信号 ,并有高信号带环绕。经等级稚和H检验 ,以及三者敏感性的两两比较 ,结果显示差异具有非常显著性意义 (P <0 .0 1)。结论 CT及低场MRI可准确地显示早期ANFH病变 。

Objective To study the staging and early imaging diagnosis of avascular necrosis of the femoral head (ANFH). Methods X ray, CT, and low field MRI were conducted and grading was performed in bilateral femoral head of 62 cases. Rank sum H test and sensitivity were completed. Results The entire cases were diagnosed as early ANFH by X ray film in 91 places. Stage I showed osteoporosis and osteosclerosis in 46 places. Stage Ⅱ showed osteosclerosis and cystic hyalomere in 45 places. 56 cases of early ANFH were discovered by CT in 86 places. Stage I showed stelliform sign distortion and osteoporosis and osteosclerosis in 34 places. Stage Ⅱ showed osteosclerosis and cystic hyalomere in 30 places. Stage Ⅲ showed meniscus sign in 22 places. Low field MRI displayed only 44 cases (73 places) of early ANFH. Stage I displayed the macular shape low or high signal intensity on T1 weighted and GRL image in 30 places. Stage Ⅱ displayed the irregular shape low or equal or high signal on T1 weighted and GRL image in 23 places. Stage Ⅲ displayed the flaky low signal and curve high signal on T1 weighted and GRL image in 20 places. Rank sum H test and sensitivity compare were striking ( P <0.01). Conclusions CT and low field MRI could exactly display early ANFH. Sensitivity and diagnostic value of low field MRI is superior to CT and X ray film.