小腿平衡稳态自由进动序列非增强MR血管成像与增强MR血管成像的对比

目的通过与增强磁共振血管成像(CE MRA)图像比较,探讨3.0T MR小腿血流敏感散相(FSD)MRA的可行性。方法收集20例可疑下肢动脉疾病患者,行小腿FSD MRA及下肢CE MRA,比较其图像质量;并以CE MRA为诊断标准,判断FSD MRA的诊断效能。结果 FSD MRA有效FOV约为(275.93±29.76)mm,图像质量评价观察者间一致性良好(Kappa=0.81,P0.01)。基于血管节段,FSD MRA图像质量评分(3.66±0.81)分]略优于CE MRA(3.49±0.87)分,P=0.05],可用于诊断的血管节段数间两者差异无统计学意义FSD MRA:97.65%(166/170),CEMRA:98.24%(167/170);P=0.32]。基于患者,FSD MRA及CE MRA的图像质量差异无统计学意义(3.25±1.06)分vs(2.94±1.06)分,P=0.40]。血管狭窄程度评价观察者间一致性良好(Kappa=0.81,P0.01)。基于血管节段,FSD MRA与CE MRA对于血管狭窄程度评价的符合率为84.34%;FSD MRA检测血管狭窄的敏感度、特异度、阳性预测值和阴性预测值分别为96.41%、93.04%、84.06%和98.53%。基于患者,FSD MRA与CE MRA评价血管狭窄程度差异无统计学意义(3.27±1.10)分vs(3.27±1.10)分,P=1.00]。结论 FSD应用于3.0T MRA可为下肢动脉病变提供一项可靠的非增强MRA检查方法。

Comparison of flow-sensitive dephasing-prepared steady-state free precession MR angiography and contrast-enhanced MR angiography in lower leg

Objective To evaluate the feasibility of flow-sensitive dephasing (FSD)-prepared steady-state free precession (SSFP) MR angiography (MRA) for imaging infragenual arteries at 3.0T, with contrast enhanced MR angiography (CE MRA) as reference. Methods Totally 20 patients with suspicion of lower extremity arterial disease underwent routine CE MRA and FSD MRA. Image quality and stenosis degree of infragenual arteries from both techniques were independently evaluated and compared. Taking CE MRA as standard, diagnostic performance of FSD MRA were judged. Results Useful FOV on frequency direction of FSD MRA was (275.93±29.76)mm. Intra-observer consistency was good on image quality assessment (Kappa=0.81, P<0.01). On vascular segments basis, image quality score of FSD MRA (3.66±0.81) was slightly higher than that of CE MRA (3.49±0.87, P=0.05). There was no difference in the number of diagnostic segments between FSD MRA and CE MRA (97.65% 166/170] vs 98.24% 167/170], P=0.32). On patients basis, there was no significant difference of image quality between CE MRA and FSD MRA (2.94±1.06 vs 3.25±1.06, P=0.40). Intra-observer consistency was good on arterial stenosis score assessment (Kappa=0.81, P<0.01). On vascular segmental basis, total agreement of arterial stenosis degree assessment between FSD MRA and CE MRA was 84.34%, the sensitivity, specificity, positive predictive value, and negative predictive value of FSD MRA for the detection of significant stenosis was 96.41%, 93.04%, 84.06%, and 98.53%. On patients basis, there were no significant difference of arterial stenosis degree scores between FSD MRA and CE MRA (3.27±1.10 vs 3.27±1.10, P=1.00). Conclusion FSD MRA performed on at 3.0T can provide reliable non contrast-enhanced MRA.