Dodd G D, Kaufman P N, Bracken R B
Department of Radiology, University of Cincinnati School of Medicine, Ohio.
J Urol. 1991 Mar;145(3):644-6. doi: 10.1016/s0022-5347(17)38412-4.
Recent clinical studies using duplex Doppler sonography identified an alteration in renal arterial blood flow in obstructed hydronephrotic kidneys that reportedly can be used to distinguish obstructive from nonobstructive collecting system dilatation. We attempted to verify these clinical findings and establish the temporal relationship of the alteration in the Doppler spectrum to the onset of urinary obstruction by evaluating surgically induced urinary obstruction in dogs. We performed laparotomies on 11 dogs, with the left ureter isolated and ligated in five dogs, and left intact in six dogs (control group). Duplex Doppler examination of the left renal arteries performed nine times during the first postoperative month identified a statistically significant difference (p less than .05) in the Doppler resistive index calculation between the two groups on days 1, 2, 4, and week 4. A resistive index discriminatory threshold of 0.7 (greater than 0.7, obstructed; less than 0.7, nonobstructed) produced a test sensitivity of 74% and specificity of 77%. We conclude from our study that renal arterial duplex Doppler sonography can detect a change in renal perfusion as a result of urinary obstruction and that this change can be detected as early as 24 hours after obstruction. However, high false-positive and false-negative rates may limit the ability of this modality to reliably distinguish obstructive from nonobstructive collecting system dilatation.
最近，采用双功多普勒超声的临床研究发现，梗阻性肾积水肾脏的肾动脉血流存在改变，据报道这种改变可用于区分梗阻性与非梗阻性集合系统扩张。我们试图通过评估犬手术诱导的尿路梗阻来验证这些临床发现，并确定多普勒频谱改变与尿路梗阻发生之间的时间关系。我们对11只犬进行了剖腹手术，其中5只犬分离并结扎左输尿管，6只犬左输尿管保持完整（对照组）。术后第一个月内对左肾动脉进行9次双功多普勒检查，结果显示在术后第1天、第2天、第4天和第4周时，两组间多普勒阻力指数计算存在统计学显著差异（p<0.05）。阻力指数鉴别阈值为0.7（大于0.7为梗阻，小于0.7为非梗阻）时，检测敏感性为74%，特异性为77%。我们从研究中得出结论，肾动脉双功多普勒超声可检测到尿路梗阻导致的肾灌注变化，且这种变化在梗阻后24小时即可检测到。然而，高假阳性率和假阴性率可能会限制这种检查方式可靠区分梗阻性与非梗阻性集合系统扩张的能力。
