A flexible annular array imaging platform for micro-ultrasound

Abstract

Micro-ultrasound is an invaluable imaging tool for many clinical and preclinical applications requiring high resolution (approximately several tens of micrometers). Imaging systems for microultrasound, including single-element imaging systems and linear-array imaging systems, have been developed extensively in recent years. Single-element systems are cheaper, but linear-array systems give much better image quality at a higher expense. Annular-array-based systems provide a third alternative, striking a balance between image quality and expense. This paper presents the development of a novel programmable and real-time annular-array imaging platform for microultrasound. It supports multi-channel dynamic beamforming techniques for large-depth-of-field imaging. The major image processing algorithms were achieved by a novel field-programmable gate array technology for high speed and flexibility. Real-time imaging was achieved by fast processing algorithms and high-speed data transfer interface. The platform utilizes a printed circuit board scheme incorporating state-of-the-art electronics for compactness and cost effectiveness. Extensive tests including hardware, algorithms, wire phantom, and tissue mimicking phantom measurements were conducted to demonstrate good performance of the platform. The calculated contrast-to-noise ratio (CNR) of the tissue phantom measurements were higher than 1.2 in the range of 3.8 to 8.7 mm imaging depth. The platform supported more than 25 images per second for real-time image acquisition. The depth-of-field had about 2.5-fold improvement compared to single-element transducer imaging.

Review of Current Simple Ultrasound Hardware Considerations, Designs, and Processing Opportunities

“…They consist in a "pulser" creating the high-voltage pulse, a "receiver" protecting the downstream components, a "Time Gain Compensation" (TGC) amplifier to prepare the signal to the "Analog to Digital Converter" (ADC), which digitizes this signal. Several groups of researchers have used this functional approach to design and implement relatively complex, research-friendly equipment (Boni, Bassi, Dallai, Guidi, Meacci, et al 2016;Boni, Bassi, Dallai, Guidi, Ramalli, et al 2012;Boni, A. C. H. Yu, et al 2018;W. Qiu et al 2012;Lévesque 2011) and simpler designs (Carotenuto, Caliano, Caronti, et al 2005;Richard, Zar, and Solek 2008;Taylor, Jonveaux, and Caskey 2017).…”

“…In some designs, an additional microcontroller is set up between the FPGA and a USB bus (Pashaei, Roman, and Mandal 2018;Schneider et al 2010), which can provide the FPGA with a configuration on the fly and allow access to the computation platform to set up the pulse-echo sequence parameters (J. R. Raj, S. M. K. Rahman, and Anand 2017; J. Raj, Smk, and Anand 2016;Weibao Qiu et al 2013). This uses in particular the Cypress families, either in USB 2 (Hu, Xingqun Zhao, and L. Xia 2011;Richard, Zar, and Solek 2008) or USB 3 (Lewandowski, Sielewicz, and Walczak 2012;Weibao Qiu, J. Xia, et al 2018;Y.…”

Development of a High-Frequency Ophthalmic Real-Time Ultrasound Imaging System Based on a 20 MHz Annular-Array Transducer

“…At present, single-element transducers, which have a single xed physical focus and are designed before and after the retina, are still generally used in ophthalmic ultrasound imaging systems in the clinic [13].…”

“…Compared to a high-frequency linear-array transducer, annular-array transducers are more suitable for the unique structure of the human eye tissue [15]. Additionally, the low number of annular-array imaging channels reduces the complexity of the system and the cost of commercialization [13], which is conducive to clinical application and promotion.…”

Secured computed tomography scanner using a random bit

“…Current medical machines can share patient data through secured communication channels, such as wirelines of the cable network and wireless transmission lines [ 1 , 2 , 3 , 4 ]. However, access from secured channels to private communication devices, such as tablets or cellular phones, has been adopted because of immediate data necessity to healthcare workers [ 5 , 6 , 7 , 8 , 9 ].…”