[Importance of different imaging methods in diagnosis of significant urodynamically uretropelvic junction obstruction in children with congenital hydronephrosis].

UNLABELLED: There are many controversies related to diagnosis of significant urodynamically uretropelvic junction obstruction (UPJO) in children with congenital hydronephrosis (CHN). We compared three imaging methods: ultrasonography (US), diuretic renography (DR) and urography. We studied 23 children with CHN in mean age 6.8 +/- 10.4 months. Despite similar antero-posterior kidney diameter in US, an obstruction of urinary flow was seen significantly more often in urography than in DR. Agreement between DR and urography was noticed only in 32% of the kidneys.

CONCLUSIONS

Recognition of UPJO in small children can be very difficult. An obstruction of urinary flow in DR can be associated not only with UPJO, but with immaturity of kidney and distensibility of the renal pelvis. Urography for imaging of CHN in small children can cause overdiagnosis of urodynamically significant UPJO and therefore too early surgical treatment.