Figure 3. Case 2: (a) ⁹⁹Tc^m-MAG3 renogram 5 days after high dose urography demonstrates severe reduction in perfusion and function of left kidney with no excretion of tracer. (b) Follow up renogram 6 weeks post placement of left nephrostomy (arrows); there is improved perfusion of left kidney, dramatic improvement in left renal function and normal excretion of tracer.