Conclusion: RI is a time-dependent physiological parameters, it can significantly enchance the diagnostic value for obstructive uropathy by analysis of the interrenal RI difference or ratio.

• 结论：梗阻发生后RI是一个时间相关性的生理参数，比较双侧肾脏的RI值可显著提高其诊断梗阻的准确性。