Dynamic contrast-enhanced MR renography for renal function evaluation in ureteropelvic junction obstruction:...

Area of Science:

• Radiology
• Nephrology
• Urology

Background:

• Ureteropelvic junction (UPJ) obstruction is a common cause of hydronephrosis.
• Accurate assessment of split renal function and obstruction type is crucial for management.

Purpose of the Study:

• To evaluate contrast-enhanced dynamic MR renography (MRR) for split renal function assessment.
• To estimate single-kidney glomerular filtration rate (SK-GFRMRR) in UPJ obstruction.
• To identify the cause of obstruction (mechanical vs. functional) using MRR.

Main Methods:

• Seventeen patients with UPJ obstruction underwent MRR and diuresis nuclear renography.
• Split renal function was compared between MRR and nuclear renography.
• Single-kidney GFR (SK-GFRMRR) was calculated using the Baumann-Rudin model.
• Renal pelvic rate of signal intensity change (PUR) was used to differentiate obstruction types.

Main Results:

• MRR showed excellent correlation with nuclear renography for split renal function (r=0.87).
• MRR estimated GFR (eGFRMRR) moderately correlated with MDRD-derived GFR (eGFRMDRD) (r=0.60).
• PUR accurately discriminated mechanical from functional obstruction (89% accuracy).

Conclusions:

• MRR is a valuable tool for assessing split renal function in UPJ obstruction.
• MRR can estimate GFR and differentiate mechanical from functional obstruction.
• MRR offers a potential
• one-stop shop
• examination for UPJ obstruction.