RENAL arterial stenosis is estimated to occur in 1% to 20% of the hypertensive population.1-4 Definite diagnosis of arterial obstruction requires the performance of renal arteriography. However, the technical aspects of this method preclude its use as a routine screening procedure. Since hypertension due to unilateral renal disease may be curable,3,5-7 a simple reliable test which would detect the presence of a stenotic lesion would be of value in the routine screening of hypertensive patients.
The radioactive renogram performed with sodium iodohippurate I 131 (I 131 Hippuran) is a simple procedure to perform both for the patient and physician. The results are readily obtainable and the amount of radiation received by the patient is negligible. These features, therefore, should make the renogram an ideal test to be used in the routine screening of hypertensive patients provided it has a high degree of reliability. The purpose of this paper