单侧激素性股骨头坏死患者正常侧股骨头脂肪含量及局部微循环：MR IDEAL-IQ和IVIM-DWI研究

目的:利用磁共振IDEAL-IQ和IVIM-DWI定量分析技术,评估单髋激素性股骨头坏死患者正常侧股骨头的脂肪含量及局部微循环状况及其临床意义.方法:将30例经临床首次确诊的单髋激素性股骨头坏死初治患者及16例性别和年龄相匹配的健康志愿者(对照组)纳入研究,所有患者行X线及MRI检查(包括常规序列、IDEAL-IQ及IVIMDWI),经图像后处理,获得股骨头脂肪含量(FF)及灌注分数(f)值.对各定量参数值在坏死侧、对侧及对照组之间的差异进行统计学分析,并采用ROC曲线评估其诊断效能.结果:对照组的FF值小于对侧组及坏死组,差异均有统计学意义(P＜0.01).坏死组的f值小于对侧正常组及对照组,差异均有统计学意义(P＜0.01).FF值的ROC曲线下面积为0.974,相应的敏感度和特异度分别为96.9％和86.7％(P＜0.01).f值的诊断效能无统计学意义(P＞0.05).结论:单髋激素性股骨头坏死患者的对侧股骨头在常规MRI上无异常形态学改变,但IDEAL-IQ及IVIM-DWI定量分析技术却能显示其内的脂肪含量和微循环状况已发生改变,为股骨头坏死的超早期诊断提供可能.

Fat content and local micro-circulation of the contralateral hip in patients with steroid-induced osteonecrosis of single femoral head:a preliminary study using MR IDEAL-IQ technique and IVIM-DWI HAN

Objective:To prospectively evaluate the efficacy of MR IDEAL-IQ (iterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation) technique and IVIM-DWI (intravoxel incoherent motion diffusion weighted imaging) in quantitatively measuring the local microcirculation and fat content of the contralateral hip in untreated patients with steroid induced osteonecrosis of femoral head (ONFH) and its clinical significance.Methods:Thirty patients with firstly diagnosed steroid induced ONFH and 16 age-and gender matched healthy volunteers as control group were included in this study,All the subjects underwent X-ray and MRI examination before treatment.Through the post-processing,f value and fat fraction (FF) of the femoral head were obtained on IVIM-DWI and IDEAL-IQ sequence respectively.The values of FF and f of ONFHs (ON group),normal FHs in contralateral side (contralateral group) and FHs in control group were compared statistically.Receiver operating characteristic curve (ROC) were used to evaluate the diagnostic efficacy of the FF and f.Results:The FF value in control group was lower than that in contralateral group and ON group (P＜0.05).The f value in ON group was lower than that in the contralateral normal group and the normal group (P＜0.01).The area under the ROC of FF was 0.974,and the corresponding sensitivity and specificity were 96.9 ％ and 86.7 ％,respectively (P＜0.01).Conclusion:No abnormal morphological changes are found in the contralateral side in patients with ONFH on conventional MRI,but the internal physiological changes of can be detected by quantitative MRI technique using IDEAL-IQ and IVIM-DWI.The Fat content increases in the contralateral normal femoral head,this may provide the possibility of ultra-early diagnosis of osteonecrosis of the femoral head.