STENOSIS AND RENOGRAPHIC CHARACTERISTICS IN RENOVASCULAR DISEASE

This study was designed to determine the degree of renal artery stenos is (RAS) which produces changes in renographic parameters. Methods: Th e angiographic severity of luminal narrowing in RAS was compared to I- 131-hippuran renographic characteristics in 72 patients who had been s elected for renal angiography because of suspected renovascular hypert ension. Results: Significant differences in T-max, T-1/2 and counts un der the curve to T-max were apparent at 30% of arterial luminal narrow ing when stenotic and nonstenotic kidneys were compared, In patients w ith unilateral RAS, the difference in counts under the T-max curve bet ween pairs of kidneys was also significantly different at 30% of steno sis. Patients with bilateral stenosis, on the other hand, could not be differentiated well from patients with essential hypertension because the T-max value on either side or the difference of T-max between the two kidneys and the values of the other parameters were similar, exce pt for the difference in counts to T-max. Based on these findings it s eems that bilateral RAS does not ''mimic'' unilateral stenosis in reno graphic terms, but rather, resembles a normal situation. Conclusion: S ignificant renographic changes can occur at 30% of arterial luminal na rrowing in renal artery disease.