High-Frame-Rate 3-D Vector Flow Imaging in the Frequency Domain

Abstract

Ultrasound vector Doppler techniques for three-dimensional (3-D) blood velocity measurements are currently limited by low temporal resolution and high computational cost. In this paper, an efficient 3-D high-frame-rate vector Doppler method, which estimates the displacements in the frequency domain, is proposed. The novel method extends to 3-D an approach so far proposed for two-dimensional (2-D) velocity measurements by approximating the (x, y, z) displacement of a small volume through the displacements estimated for the 2-D regions parallel to the y and x directions, respectively. The new method was tested by simulation and experiments for a 3.7 MHz, 256-element, 2-D piezoelectric sparse spiral array. Simulations were also performed for an equivalent 7 MHz Capacitive Micromachined Ultrasonic Transducer spiral array. The results indicate performance (bias ± standard deviation: 6.5 ± 8.0) comparable to the performance obtained by using a linear array for 2-D velocity measurements. These results are particularly encouraging when considering that sparse arrays were used, which involve a lower signal-to-noise ratio and worse beam characteristics with respect to full 2-D arrays.

Real-Time 3-D Spectral Doppler Analysis With a Sparse Spiral Array

“…All benefits and limitations of 2-D spectral Doppler can be extended to 3-D. For example, quantitative information on blood flow velocity could be, to some extent, obtained through simple angle correction or through vector flow imaging techniques that exploit either the Doppler bandwidth [55], [56], multiple transmission/reception beams [16], [57], [58], or speckle tracking [20], [23].…”

“…In recent years, massive research efforts and technological developments have brought two breakthroughs: volumetric (3-D) imaging [8]- [11] and vector Doppler [12]- [23]. Although medical doctors always need some time to fully accept new display modalities, both methodologies are mature for implementation in ultrasound machines.…”

Embedded GPU Implementation for High-Performance Ultrasound Imaging

“…A new expansion board (EXP) hosting a Jetson AGX Xavier module (NVIDIA, Santa Clara, CA, USA) [26] was designed and implemented; see Figure 1. By exploiting the embedded GPU resources, this upgrade will allow the performance of the most recent processing modalities that require a massive amount of computational resources [27,28].…”

Design, Implementation, and Medical Applications of 2-D Ultrasound Sparse Arrays

“…This problem was faced in [81] by implementing real-time 774 coded TX and matched filtering in RX on the ULA-OP 775 256 scanner, which was connected to the 256 elements corre-776 sponding to the main spiral-based Vermon probe layout (see 777 Section III-A2). The article showed that the TX of 5 μs long 778 In [98], the same spiral probe layout was used to experimentally validate a novel high frame rate 3-D vector flow imaging method. The probe here transmitted unsteered plane waves at 3.7 MHz.…”