Title: Intrarenal Arterial Doppler Evaluation in Acute Ureteric Obstruction

Authors: Dr Supriya Pakalapati, Dr G S Kejriwal, Dr CH Madhavi, Dr M Gnani

 DOI: https://dx.doi.org/10.18535/jmscr/v8i2.20

Abstract

Objective: To determine the diagnostic utility of intrarenal arterial Doppler study in ureteric obstruction. To compare intrarenal arterial doppler in patients with obstructed and non obstructed kidneys.

Materials & Methods: Study included prospective inclusion of 63 patients presenting within 24 hrs of the onset of symptoms of unilateral acute renal colic. The case group included kidney with the obstruction side and the opposite side healthy kidney considered as the control. All patients underwent USG and Doppler scan using 2-5 MHz convex probe and will be assessed for the presence or absence of pelvicalyceal system dilatation on the gray-scale images. Minimum three Doppler spectra will be obtained from interlobar arteries along the border of the medullary pyramids, and their mean RI calculated. RI of 0.70 remains the upper limit of average intrarenal resistance. CT scan will be done if ultrasonography is equivocal. If the site of obstruction is up to or proximal to L3 vertebral level, it is considered as proximal obstruction and distal if it is beyond L3 vertebral level.

Results: Resistivity Index (RI) in segmental renal arteries of all the 63 patients was significantly higher in the obstructed kidney than in unobstructed kidney (0.7 vs 0.56; p<0.001) with a sensitivity of 87.3% and specificity of 90%.

Conclusions: Doppler ultrasound is a useful diagnostic tool in the diagnosis of acute ureteric obstruction, thus preventing unnecessary CT and minimizing radiation exposure to patients. RI value > 0.7 have a very high level of specificity and sensitivity for acute ureteric obstruction.

Keywords: Intrarenal arterial Doppler; Acute renal colic; Acute ureteric obstruction; RI value.

References

  1. Sonali S Saboo, Sachin S Soni, Suresh H Saboo, Naga Ramesh Chinapuvvula, Sashidhar Kaza. Doppler sonography in acute renal obstruction. IJRIE August 2007 / Vol 17 /188-192 Issue 3.
  2. Platt JF, Rubin JM, Ellis JH, DiPietro M. Duplex Doppler US of the kidney: Differentiation of obstructive from non-obstructive dilatation. Radiology 1989; 171:515-7.
  3. Platt JF, Rubin JM, Ellis JH. Lupus nephritis: predictive value of conventional and Doppler US and comparison with serologic and biopsy parameters. Radiology 1997; 203:82-6.
  4. Gul, Hina Habib, Irum Roghani, Inayat Shah. Diagnostic accuracy of renal arterial resistive index (RI) in acute renal colic KJMS. January- June. 2014 Vol. 7, No.1.
  5. Azam Aneela, Arfan-ul-haq, Beg MA. Role of renal arterial resistive index (RI) in obstructive uropathy. J Pak Med Assoc. 2013 Dec;63(12):1511-5.
  6. Piazzese E.M, Mazzeo G.I, Galipò S, Fiumara F, Canfora C, Angiò LG. The renal resistive index as a predictor of acute hydronephrosis in patients with renal colic. J Ultrasound. 2012 Oct 14;15(4): 239-46.
  7. Ellenbogen PH, Scheible FW, Talner LB, Leopold GR. Sensitivity of gray-scale ultrasound in detecting urinary tract obstruction. AJR Am J Roentgenol 1978;130:731-3.
  8. Amis ES Jr, Cronan JJ, Pfister RC, Yoder IC. Ultrasonic inaccuracies in diagnosing renal obstruction. Urology 1982; 19:101-5.
  9. Webb JA. Ultrasonography and Doppler studies in the diagnosis of renal obstruction. BJU Int 2000;86:25-32.
  10. Gulmi FA, Felsen D, et al. Pathophysiology of urinary tract obstruction. In Walsh PC, Reti KAB, Vaughan ED, Wein AJ, eds. Campbell's Urology. 7th ed. Chapt 9. WB Saunders: Philadelphia; 1998. p. 350.
  11. Platt JF, Rubin JM, Ellis JH. Acute renal obstruction: Evaluation with intrarenal duplex Doppler and conventional US. Radiology 1993;186:685-8.
  12. Rodgers PM, Bates JA, Irving HC. Intrarenal Doppler ultrasound studies in normal and acutely obstructed kidneys. Br J Radiol1992;65:207-12.
  13. Shokeir AA, Abdulmaaboud. Resistive index in renal colic: A prospective study. BJU Int 1999;83:378-82.
  14. Platt JF, Ellis JH, Rubin JM. Role of renal Doppler imaging in the evaluation of acute renal obstruction. AJR Am J Roentgentol 1995;164:379-80.

Corresponding Author

Dr Supriya Pakalapati

Post Graduate, Dept of Radiology, Maharajah’s Institute of Medical Sciences