1024-Channel Single 5W FPGA Towards High-quality Portable 3D Ultrasound Platform

Volumetric Ultrasound (US) imaging is an emerging tech- nology for medical US applications. Typically, US imaging is 2D, where a number of vibrating elements, arranged in an array, are used to scan 2D cross-sections of the human body. In volumetric US a matrix probe of vibrating elements is used instead of the array, where conical volumes are reconstructed instead of 2D cross-sections. Today, cardiology and obstetrics are the most benefiting applications from 3D imaging, where better assessment of chamber volumes, and more expressive imaging are provided, respectively. 3D US allows the imaging of entire volumes using a single scan, unlike in 2D imaging, where multiple slices should be acquired precisely by a trained sonographer to be able to diagnose the entire structure. As a result, 3D US imaging speeds up the acquisition time, and eliminates the dependency on the presence of a trained operator during the scan. These characteristics make 3D US ideal for situations where the presence of a trained sonographer is an issue and the need to speed up the acquisition time is paramount, such as battlefields and rescue environments. How- ever, todays 3D systems [1] are bulky, expensive, and power hungry because the processing load of 3D US is orders of magnitude higher compared to conventional 2D imaging. For this reason, 3D systems are currently only available in well- equipped hospitals, and not in rural areas and underdeveloped regions where even electricity supply is an issue.

Single-FPGA 3D Ultrasound Beamformer

Federico Angiolini, Marcel Arditi, Giovanni De Micheli, Aya Mohamed Naguib Ahmed Ibrahim, Jean-Philippe Thiran, Ahmet Caner Yüzügüler

In medical diagnosis, ultrasound (US) imaging is one of the most common, safe, and powerful techniques. Volumetric (3D) US imaging, an emerging technique, is even more attractive than standard 2D imaging, as it allows for imaging without the local presence of a trained sonographer finely positioning the probe. This would be particularly useful in rescue operations, remote areas and developing countries. Unfortunately, present-day 3D imagers are expensive, bulky and power-hungry, confining them to hospitals. There is therefore a strong motivation to develop efficient electronics to enable a portable US platform that is small, cheap, and battery- operated. Beamforming (BF) is the most computationally expensive of 3D imaging. Both commercial [1] and research [2] imagers have dealt with the challenge by reducing the number of receive channels, hence simplifying the computation through the usage of far fewer elements. This comes at the cost of image quality, and the resulting machines are nonetheless still non-portable and expensive. In turn, the bottleneck of the BF process is the calculation of acoustic delays, which requires up to trillions of square roots per second. We propose a drastically more efficient architecture [3]. With geometric considerations, each delay is calculated from a small set of square roots (mapped onto CORDICs), plus two additions. In this demo, we will show the reconstruction of a 2.5M-voxel volume, supporting a transducer with 32×32 receive channels. We have fitted the architecture into a single Kintex UltraScale KU040 [4], which is unprecedented. We also extrapolated the utilization of a 80×80 instance on a Virtex UltraScale XCVU190 [4]. Table I shows the implementation results. Fig. 1 shows our beamformer custom block connected to the other FPGA subsystems. The delay calculation architecture is shown in Fig. 2. The demo setup is presented in Fig. 3, where the 3D beamformer is implemented on the FPGA, while the pre- and post-processing stages are currently performed on Matlab.

Ieee2016

Using medical images acquired during routine clinical care for research purposes: a comprehensive medical informatics approach applied to the study of brain development from birth through 2 years of age as indexed by diffusion MRI

Vincent Alexis Roch

Biologic variability and dramatic changes of brain development in children aged 0 to 2 years make it challenging to accurately detect subtle abnormalities in single Magnetic Resonance Imaging (MRI) scans. Diffusion MRI (dMRI) indices such as Apparent Diffusion Coefficient (ADC) are reliable measures of water content in the brain and thus an excellent surrogate marker for brain development. Developing robust age-specific diffusion biomarkers for quantitative measurement of normative brain evolution would enhance our ability to detect subtle alterations due to tissue injuries or neuropathological disorders. Obtaining significant numbers of normative MRI scans for this age group means redirecting clinical data from hospital databases for research purposes. Therefore, this pilot project demonstrates the feasibility of identifying, retrieving and analyzing pediatric clinical dMRI data to investigate normal brain development from birth to 2 years. Research Patient Data Registry (RPDR) at Massachusetts General Hospital (MGH) was used to collect patient medical information and identify healthy children according to radiology reports. Corresponding MRI data were retrieved from MGH Picture Archiving and Communication System (PACS) using the prototype of Medical Imaging Informatics Bench to Bedside (mi2b2) software. A specific pipeline was created to handle the volume of studies and extract technical scan information used to identify comparable diffusion series; 193 studies were used for analysis. Two markers, whole brain average of ADC and Fractional Anisotropy (FA) values (WBAADC and WBAFA), were computed for each patient, their age-evolution across patients was investigated with different models. WBAADC and WBAFA seem to exhibit biexponential decay and increase respectively and might be gender-specific. These results have clinical implications for potentially determining the health status of an unknown individual, and research utility for continued development of these tools.

2011

Live Demonstration: Inexpensive 1024-Channel 3D Telesonography System on FPGA

Federico Angiolini, Marcel Arditi, Giovanni De Micheli, Damien Doy, Aya Mohamed Naguib Ahmed Ibrahim, Jean-Philippe Thiran

Volumetric ultrasound (US) is a very promising development of medical US imaging. An under-exploited advantage of volumetric US is the mitigation of the strict probe positioning constrains necessary to acquire 2D scans, potentially allowing the decoupling of US image acquisition and diagnosis. However, today’s 3D US systems are large and beset by high power and cost requirements, making them only available in well-equipped hospitals. In this work [1], [2], we propose the first telesonography-capable medical imaging system that supports up to 1024 channels, on par with the state of the art. As a first embodiment, we have implemented our design in a single development FPGA board of 26.7cm×14cm×0.16cm, with an estimated power consumption of 6.1 W. The imager exploits a highly scalable architecture which can be either downscaled for 2D imaging, or further upscaled on a larger FPGA. Moreover, our design supports two types of data inputs: real-time via an optical connection and offline over Ethernet. The reconstructed images can be visualized on an HDMI screen. The estimated cost of the proposed prototype materials is less than 4000e. TABLE I shows the resources utilization of the current design and the extrapolated utilization in case of further upscaling on a larger FPGA.

2017

Vincent Alexis Roch

2011

Single-FPGA 3D Ultrasound Beamformer

Federico Angiolini, Marcel Arditi, Giovanni De Micheli, Aya Mohamed Naguib Ahmed Ibrahim, Jean-Philippe Thiran, Ahmet Caner Yüzügüler

Ieee2016