直接超声参数在肾动脉狭窄诊断中的应用研究

目的 探讨内径狭窄≥50%肾动脉狭窄（RAS）的直接超声参数特点及其诊断价值.方法 经彩色多普勒血流成像（CDFI）检查后并接受肾动脉造影的89例患者共177条肾动脉构成研究组,测量了肾动脉峰值流速（RPSV）、肾动脉与腹主动脉峰值流速比值（RAR）、肾动脉与肾动脉峰值流速比值（RRR）、肾动脉与段动脉峰值流速比值（RSR）和肾动脉与叶间动脉峰值流速比值（RIR）.肾动脉造影显示肾动脉内径狭窄≥50%者确定为RAS.使用ROC曲线分析确定最佳诊断指标.计算这些流速指标不同阈值的敏感性、特异性、阳性预测值、阴性预测值和准确率.结果 在肾动脉造影显示的177条肾动脉中,80条狭窄程度为50%～99%,7条闭塞.在狭窄程度50%～99%的80条肾动脉中,动脉粥样硬化性RAS 46条,大动脉炎RAS 20条,纤维肌性发育不良性RAS 12条,其他病因2条.肾动脉CDFI检查成功率为98.9%（175/177）.RPSV、RAR、RRR、RSR、RIR最佳阈值分别为170 cm/s、2.3、2.0、3.8、5.5.RPSV、RSR和RIR均获得较好的诊断效果（准确率均大于87%）,RAR和RRR的诊断敏感性较差（分别为79%和80%）.结论 对于狭窄≥50%的RAS,RPSV、RIR和RSR均是较好的诊断指标,RAR和RRR的诊断敏感性较差.影响肾动脉和腹主动脉PSV的因素都可导致RAR的诊断准确性下降,而PSV后比参数受腹主动脉PSV的影响较小,且各种原因所致肾动脉主干、肾内动脉PSV等成比例改变对PSV后比参数的影响也较小,其能明显弥补RAR的一些不足.

Evaluation of renal artery stenosis by direct parameters of Doppler sonography

Objective To evaluate the characteristics and diagnostic value of direct parameters of Doppler sonography in the diagnosis of renal artery stenosis （RAS） （diameter reductions≥50% ） . Methods A total of 89 patients with 177 renal arteries detected by color Doppler flow imaging and referred to renal arteriography were included. Five Doppler parameters including renal peak systolic velocity （RPSV） , renal aortic ratio （RAR）, renal-renal ratio （RRR）, renal-segmental ratio （RSR） and renal-interlobar ratio （RIR） were measured. The arteries were stenosed on renal arteriography in case of a diameter reduction of 〉 50%. The sensitivity, specificity, and negative predicting value, positive predicting value and accuracy at various cut-off values were calculated. Results In the 177 main renal arteries demonstrated by renal arteriography, there were 7 occlusion and 80 stenoses （ diameter reduction 50% - 99% ）. Among the 80 stenoses, 46 were caused by atherosclerosis, 20 by Takayasu＇s arteritis, 12 bv fibromuseular dysplasia and 2 by other etiological reasons. Doppler examination was technically successfol in 98. 9% of renal arteries （175/177）. The best cut-off values for the 5 parameters （RPSV, RAR, RRR, RSR, RIR） were 170 cm/s, 2.3, 2.0, 3.8, 5.5, respectively. The parameters of RPSV, RSR and RIR had better diagnostic efficiency （ 〉 87% accuracies）. Both RAR and RRR bad sensitivities of 79% and 80%, respectively. Conclusions For the detection of RAS （ diameter reduction ≥50% ） , the RPSV, RIR and RSR are indicators with high quality, while both RAR and RRR have sensitivities with poor quality. The factors influencing the PSV in both renal artery and abdominal aorta can decrease diagnostic accuracy of RAR. However, the parameter of post-PSV ratios and the factors which make a proportional change in PSV in both main renal artery and intrarenal arteries are rarely influenced by PSV in abdominal aorta .