Drainage of the renal cortex in MAG3-F0 for diagnosis of obstruction and evaluation of laparoscopic pyeloplasty

Objectives The objective of this study was to utilize diuretic renography with MAG3-F0 to assess drainage of the cortex in order to determine the need for laparascopic pyeloplasty (LP) and evaluate its efficacy, irrespectively of drainage of the collecting system.

Methods MAG3-F0 renal scans were performed pre- and post-operatively on 30 patients who underwent LP for treatment of suspected ureteropelvic junction obstruction. Drainage of the cortex was evaluated using cortical renograms while renal function was evaluated using 1-2 min split renal function (SRF). The patients were classified in two groups: Group1 with 13/30 patients had abnormal cortical drainage and required LP, while Group2 with 17/30 patients had normal drainage but LP was performed based on other clinical criteria.

Results Post-operative MAG3-F0 studies demonstrated improvement of cortical drainage and SRF for patients in Group1 and no significant improvement or change for patients in Group2, who did not need operation. Additionally, serial MAG3 scans confirmed that patients in Group1 post-operatively maintained normal cortical drainage and renal function and did not require additional intervention.

Conclusions Evaluation of drainage of renal cortex in MAG3-F0 studies, irrespectively of the collecting system, can indicate the presence of kidney obstruction and determine the need for LP. Drainage of renal cortex can be also used as an index to study the effectiveness of LP