磁共振灌注成像诊断在股骨头缺血性坏死的初步应用

目的 探讨磁共振(MR)灌注成像在股骨头缺血性坏死时的表现及对早期诊断的意义.方法 对北京中日友好医院21例临床拟诊为股骨头缺血性坏死患者和髋关节疼痛患者进行常规MR、MR灌注成像和Gd-DTPA增强MR检查.结果 21例中MRI表现为股骨头缺血性坏死10例,其中双侧5例、单侧5例(共15个股骨头).按Froberg等MRl分期,Ⅰ期见于2个股骨头;Ⅱ期见于4个股骨头;Ⅲ期见于2个股骨头;Ⅳ期见于7个股骨头.增强扫描示无强化2个股骨头、轻微强化10个股骨头和较明显强化3个股骨头.MR灌注成像曲线表现为:(1)MaxSR减小,伴或不伴有TTP延迟,平均通过时间(MTT)延长(n=5);(2)灌注曲线平直(n=8);(3)曲线基线明显升高,缓慢下降后缓慢上升至基线水平后继续上升(n=2).结论 MR灌注成像可反映股骨头的血流灌注情况.灌注曲线可反映病理改变过程,评估组织活性,有利于临床医师判断病程分期,为选择治疗方案提供依据.并使在微循环损伤阶段发现病变成为可能.

Preliminary clinical application of magnetic resonance perfusion imaging of avasaular necrosis of femoral head

Objective To evaluate the features and value of magnetic resonance (MR) perfusion imaging (PI) of avascular necrosis of the femoral head (ANFH). Methods MR, gadolinium (Gd)enhanced MR and MRPI were performed in 21 patients with a probable diagnosis of ANFH. Results MRI showed that 10 of the 21 patients were with ANFH,5 in bilateral femoral heads, and 5 in unilateral femoral head, totally in 15 femoral head, 2 at the Froberg stage Ⅰ , 4 at the stage Ⅱ, 2 at the stage Ⅲs, and 7 at the stage Ⅳ. Gd-enhanced MR showed that 2 femoral heads were not enhanced, 10 were slightly enhanced,reduction) was decreased with or without prolonged TrP(time to peak), the MTT (mean transit time) was declined, and then slowly increased (n=2). Conclusion MRPI reflects the blood perfusion of the femoral head. The type of the MRPI cure reflects the pathological progression of ANFH, evaluates the activity of the femoral head, and is useful to the clinical physicians to estimate the stage of ANFH and choose treatment for the patients. MRPI is a method in diagnose ANFH at the initial microcirculatory injury stage.