Renal Venous Doppler Study in Obstructive Uropathy

Abstract

Introduction: Obstructive uropathy is very common cause of pain abdomen. Recognition of the cause of the pain and level of obstruction is the goal. Ultrasound is the primary modality used for detection and characterization of obstructive uropathy along with conventional radiographs. Obstructive uropathy in early stages can be difficult to diagnose using standard B-mode USG or arterial sensitive index. Aim: The purpose of this study is to evaluate the diagnostic accuracy of renal venous doppler ultrasound in diagnosing acute obstructive uropathy either alone or in addition to arterial doppler study of inter lobar arteries. As there is limited literature available till date on Indian population regarding renal venous doppler in obstructive uropathy, this study can be useful. Materials and Methods: Fifty patients presenting with features suggestive of obstructive uropathy were studied and compared with non-obstructed kidney of the same patient. Fifty normal individuals were studied and taken as controls. Results: The mean venous impedance index on the obstructed side (0.26 ± 0.07) was less than the mean venous impedance index on the unobstructed side (0.41 ± 0.08) and was statistically highly significant. There was no statistically significant difference in mean arterial Resistivity Index (RI). Conclusion: Thus renal venous doppler study is a reliable tool in diagnosing cases of acute obstructive uropathy. Though its use as single parameter to identify obstruction still needs further studies, it can be used in conjugation with b mode ultrasound and arterial Doppler to identify obstruction.

Keywords

• end diastolic velocity
• impedance index
• non obstructive kidneys
• peak systolic velocity
• resistive index
• ultrasound