Quantitative colour Doppler and greyscale ultrasound for evaluating prostate cancer

Abstract

Introduction Although transrectal ultrasound is routinely performed for imaging prostate lesions, colour Doppler imaging visualizing vascularity is not commonly used for diagnosis. The goal of this study was to measure vascular and echogenic differences between malignant and benign lesions of the prostate by quantitative colour Doppler and greyscale transrectal ultrasound. Methods Greyscale and colour Doppler ultrasound images of the prostate were acquired in 16 subjects with biopsy-proven malignant or benign lesions. Echogenicity and microvascular flow velocity of each lesion were measured by quantitative image analysis. Flow velocity was measured over several cardiac cycles and the velocity–time waveform was used to determine microvascular pulsatility index and microvascular resistivity index. The Wilcoxon rank sum test was used to compare the malignant and benign groups. Results Median microvascular flow velocity of the malignant lesions was 1.25 cm/s compared to 0.36 cm/s for the benign lesions. Median pulsatility and resistive indices of the malignant lesions were 1.55 and 0.68, respectively versus 6.38 and 1.0 for the benign lesions. Malignant lesions were more hypoechoic relative to the surrounding tissue, with median echogenicity of 0.24 compared to 0.76 for the benign lesions. The differences between the malignant and benign groups for each measurement were significant (p < 0.01). Conclusion Marked differences were observed in flow velocity, microvascular pulsatility, microvascular resistance, and echogenicity of prostate cancer measured with quantitative colour Doppler and greyscale ultrasound imaging. Vascular differences measured together with echogenicity have the combined potential to characterize malignant and benign prostate lesions.

Transrectal ultrasound vector projectile imaging for time‐resolved visualization of flow dynamics in the male urethra: A clinical pilot study

“…CE‐UroVPI has a temporal resolution of 1250 fps (approx. 30 to 100 times higher than that of conventional color Doppler imaging for the prostatic urethra 26,27 ), and pixel‐wise estimation of flow vectors (magnitude and angle) that enables quantitative measurement of flow speed distribution in curved male urethra and detecting complex flow patterns such as vortexes. This study validated that CE‐UroVPI can visualize and assess the flow dynamics in the urethra at different voiding phases (Figure 3), and its characteristics outperform the previous attempts that assessed intra‐urethra urinary flow only in the stational maintenance phase and a limited urethra region with less curvature 5,27,28 …”

Multiparametric ultrasound of prostate: role in prostate cancer diagnosis

“…Color Doppler ultrasonography (CDUS) has been proposed as a tool to improve the accuracy of TRUS using other parameter than echogenicity on regular B-mode US. 12 The vascularity of a suspicious hypoechoic area on regular gray-scale B-mode US can be identified and characterized by CDUS or Power Doppler ultrasonography (PDUS). 32 Although PDUS is more sensitive than CDUS in detecting slow blood flow, PDUS has not shown better PCa detection than CDUS.…”

“…33 Therefore, an increased number of shifts is associated with neovascularization in that tissue. 22,17 The Doppler flow patterns between malignant and benign lesions were assessed by Ashi et al 12 In that series, the median velocity of PCa lesions was 1.35 cm/s compared with a median of 0.36 cm/s for their benign counterparts. In addition to that, the flow was continuous and phasic for malignant lesions versus irregular on benign ones.…”

“…Recent advances in ultrasonography (US) technology established US modalities, such as Doppler-US, HistoScanning, contrast-enhanced ultrasonography (CEUS), elastography, and micro-ultrasound (micro-US). 12 – 17 Although these new modalities have some limitations including need of specialized equipment, inconsistent results, lack of standardizations, and external validation, the early results of multiparametric US have been promising ( Table 1 ). 18 – 23 The ‘Multiparametric Ultrasound (mpUS)’ is attracting attention in the field of Urology and Radiology.…”

Radiogenomic analysis of ultrasound phenotypic features coupled to proteomes predicts metastatic risk in primary prostate cancer

“…The study has used contrast-enhanced ultrasound parameters to predict bone metastasis [ 7 ]. Some studies have established a scoring system or machine learning model based on various ultrasonic image features and measurements, which are essential in identifying malignant prostate cancer and assessing prostate cancer risk [ 8 – 10 ]. However, studies still lack evaluating ultrasound image features to predict whether prostate cancer has metastasized.…”