to investigate the feasibility of videodensitometry in assessing the renal parenchymal perfusion in patients with renal artery stenosis before and after stenting.Materials and Methods
angiographic data of 101 patients with and 55 patients without renal artery stenosis were analyzed by means of videodensitometry, using ≪ Multivox≫ software. Time-density curves were calculated for renal parenchyma and parenchymal perfusion parametrs were measured as shown on fig. 1. Parenchymal perfusion coefficient was measured as (max intensity - min intensity)/max intensity. All patients included in study underwent renal arteries duplex ultrasound and kidneys ultrasound examination. Levels of blood pressure and kidney function as a clinical signs of renovascular hypertension were assessed.In 41 patients, who underwent renal artery stenting for atherosclerotic renal artery stenosis, videodencitometric parameters of renal blood flow before and after renal artery stenting were compared.Results
videodensitometric analysis allows detecting statistically significant differences in parenchymal perfusion between kidneys with and without renal artery stenosis. A grade of changes in parenchymal perfusion correlates with angiographicaly measured degree of renal artery stenosis and renal artery blood flow velocity. Also, the videodensitometry reveals differences in renal perfusion before and after renal artery stenting. However, these differences were significant only in patients with renal artery stenosis more that 75%, with peak systolic velocity more that 250 cm/s.Conclusion
videodensitometric perfusion parameters can be used to assess the effect of renal artery stenosis on parenchymal blood flow. Thus, videodensitometry extends the diagnostic capability of the angiographic study.