Guidance Imaging Modality Influences Pulsed-Wave Doppler Measurements: Comparative Evaluation of B-mode, Power Doppler, CCDS, MVI, and B-Flow

Abstract Pulsed-wave (pw) Doppler is widely used for quantitative blood flow assessment, but its accuracy depends on the guidance imaging modality used to position the sample volume. Modern ultrasound systems provide several guidance modes – B-mode, color-coded duplex sonography (CCDS), power Doppler, B-flow, and microvascular imaging (MVI) – the influence of which on pw-Doppler measurements has not yet been systematically evaluated. In this prospective paired-methods study, pw-Doppler flow of the brachial artery was measured in 454 adults while simultaneously using four guidance imaging modalities (CCDS, power Doppler, B-Flow, MVI). B-mode pw-Doppler measurements were interspersed as a reference. Differences in measured flow were analyzed using Bland-Altman statistics, analysis of variance, and linear mixed-effects models. CCDS, power Doppler, and B-flow produced pw-Doppler flow values closely matching the interpolated B-mode reference (bias < 6 mL/min). In contrast, MVI consistently underestimated flow (bias 50–60 mL/min, p < 0.001) and showed an additional flow-dependent bias. Bland–Altman analyses demonstrated markedly wider limits of agreement for MVI. No patient-related factors explained these deviations. Guidance imaging modality significantly affects pw-Doppler flow measurements. MVI introduces systematic, flow-dependent underestimation, whereas CCDS, power Doppler, and B-flow yield consistent results. MVI should not be used when accurate pw-Doppler quantification is required.