ABSTRACT
A series of six hemodialysis vascular access patients was evaluated with duplex Doppler sonography and angiography to identify Doppler sonographic parameters that are predictors of venous outflow stenosis. This preliminary series indicates that no venous outflow stenosis was present angiographically when the resistive index gradient across the venous anastomosis is less than or equal to zero and a significant venous outflow stenosis (50 to 100%) was present when the resistive index gradient is 0.15 or greater (P = 0.002, r = 0.963). Doppler acquisition of resistive index gradients across regions of venous outflow is a promising, noninvasive means of rapid radiologic evaluation of hemodialysis graft patients, especially when the need for angiography is equivocal.