Objective: We examined the change in the renal function in the normal side kidney before and after a nephrectomy, by means of a newly developed diuretic renography technique utilizing Tc 99m-mercaptoacetyltriglycine (MAG3).
Materials and methods: Forty patients who underwent a nephrectomy were evaluated using MAG3 diuretic renography. We measured the effective renal plasma flow (ERPF) and Tmax time before and after a nephrectomy. The effects of the patient age and the preoperative ERPF of ill side kidney on the post operative ERPF were then assessed statistically.
Results: The ERPF increased by an average of 44.8 ml/min at 2 weeks after a nephrectomy, but it decreased by an average of 24.3 ml/min at 3 months after a nephrectomy. The Tmax time decreased by an average of 0.58 min at 2 weeks, but thereafter increased by an average of 0.58 min at 3 months after a nephrectomy. The correlation coefficient between the rate of increase in the ERPF and the patient age was 0.197.
Conclusions: The rise of renal function in terms of ERPF and the Tmax time was observed at 2 weeks post-nephrectomy. However, this effect disappeared at 3 months post-nephrectomy. These data demonstrated that the rise in the renal function of the normal-side kidney in such patients was only temporary.