COMPARISON OF DIURETIC SONOGRAPHY AND DIURETIC RENAL SCAN IN DISTINCTION OF OBSTRUCTIVE AND NONOBSTRACTIVE HYDRONEPHROSIS

Sonography is a valid paraclinic test for evaluation of urinary tract obstruction it can evaluate urinary tract only from static point of view. We want to evaluate the dynamism of urinary flow by inducing diuresis. In our study 32 patients were selected and diuretic renal scan were perfromed in all of the patients. Diameter of the renal pelvis were measured before and after diuresis.(by real time sonography). On the basis of previous studies, obstruction were defined as increasing of renal pelvis diameter greater than seven milimeters. Then results of these metods compared. In the initial sonographic evaluation 50.97% of kidneys were hydronephrotic, therefor were considered obstructive. After diuresis 26.6% of kidneys were considered obstructive. On the basis of diuretic renal scan 23.4% of kidneys were obstructive. In two patients with renal malrotation, results of diuretic sonography and diuretic renal scan were not compatible. We concluded that diuretic sonography in comparison with diuretic renal scan, with 93.3% sensitivity and 94.85% specificity, can differentiate obstructive from nonobstructive hydronephrosis. This method can be used in initial evaluation of suspected urinary tract obstruction and in follow up of patients after treatment.