Evaluation of Congenital Hydronephrosis with Static and Dynamic Magnetic Resonance Urography in Comparation to Dynamic Renal Scintigraphy

Introduction: Congenital hydronephrosis (CH) is a condition with dilated renal pelvis with or without dilation of renal calyces. Aim: To examine the role of magnetic resonance urography in the detection of congenital hydronephrosis in comparison to dynamic renal scintigraphy (DRS). Patients and methods: Resarch included 58 (n=58) patients with diagnosis of congenital unilateral or bilateral dilatation of kidney duct system. Each patient had a one-time or multiple hospitalization at the Nephrology Department of the Pediatric Clinic, with performed: ultrasound which confirmed CH, voiding cystourethrography / voiding urosonography was confirmed based on which the vesicoureteral reflux (VUR) was established / excluded, dynamic renal scintigraphy and magnetic urography (analysis was made by CHOP-fMRU software) on the basis of which the uterine anatomy and the relative renal function were evaluated. Results: Male patients were represented in 40 cases (69%). The average age was 4.4 ± 4.3 years with the youngest patient at the age of 2 months, and the oldest was 17 years old. According to diagnostic entities, the most common diagnosis was ureteropelvic junction (UPJ) obstruction in over half of cases (30 or 51.7%), followed by subjects with ureterovesical junction (UVJ) obstruction (11 or 19%), VUR was recorded in 9 (15.5%) cases, and pyelon fissus in 7 (12.1%), and one case (1.7%) was recorded with bilateral megaureter. Comparison of the value of the renal function obtained with DRS and CHOP-fMRU methods shows that there were no statistically significant differences between two methods. In the case of right kidney, the mean DRS value was 53.4 ± 18.4% (range 13-100%), while CHOP-fMRU was 51.8 ± 22.4 (range 0-96.7%). In the case of left kidney, the average value according to the DRS method was 46.9 ± 18.9% (range 0-87%) and according to CHOP-fMRU 47.6 ± 21.5% (range 8.3-100%). The correlation coefficients of both right and left kidneys show a highly statistically significant correlation between these two methods. Conclusion: Magnetic resonance urography in the pediatric population in CH based on results should be an integral part of the management of these patients, especially in congenital obstructive uropathy, in complex and associated congenital anomalies, as it provides morphological and functional data on the state of the kidneys and urinary tract.