The use of captopril-DTPA scanning in the diagnosis of atherosclerotic renal artery stenosis in patients with impaired renal function. 
We have analyzed our use of captopril-diethylene-triaminepentaacetic acid (DTPA) scanning in patients presenting to the Royal Free Hospital predominantly with renal impairment.  The sensitivity was found to be as good in patients with bilateral disease or disease of a single kidney as in patients with unilateral disease.  On a number of occasions, though, the scan suggested unilateral disease when bilateral disease existed.  There were, however, a large number of patients for whom captopril-DTPA scanning was not performed because of severe renal impairment or the possibility of renal artery stenosis in a single functioning kidney.