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Weibao Qiu - IEEE Xplore Author Profile

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Holographic acoustic tweezers have various biomedical applications due to their ability to flexibly and rapidly synthesize acoustic fields for manipulating single or multiple particles. Existing multiparticle manipulation techniques are usually realized by precisely designing the incident wave’s phase distribution to synthesize a complex and steady-state acoustic field containing multiple acoustic...Show More
Ultra-high frequency (UHF, >100 MHz) ultrasound imaging has significant potential applications in musculoskeletal anatomy, skin, oral mucosa, and the eyes as a new high-resolution imaging technique. However, large acoustic attenuation of biological tissues greatly limits the depth of penetration of UHF ultrasound. Improving penetration depth while maintaining high-definition images is of clinical ...Show More
Coherent plane-wave compounding technique enables rapid ultrasound imaging with comparable image quality to traditional B-mode imaging that relies on focused beam transmission. However, existing methods assume homogeneity in the imaged medium, neglecting the heterogeneity in sound velocities and densities present in real tissues, resulting in noise reverberation. This study introduces the Reverse ...Show More
A fully-sampled two-dimensional (2D) matrix array ultrasonic transducer is essential for fast and accurate three-dimensional (3D) volumetric ultrasound imaging. However, these arrays, usually consisting of thousands of elements, not only face challenges of poor performance and complex wiring due to high-density elements and small element sizes but also put high requirements for electronic systems....Show More
Objective: The acquisition of real-time portal vein pressure (PVP) is important for portal hypertension (PH) discrimination to monitor disease progress and select treatment options. To date, the PVP evaluation approaches are either invasive or noninvasive but with less stability and sensitivity. Methods: We customized an open ultrasound scanner to explore in vitro and in vivo the ultrasound contra...Show More
Acoustic droplet ejection (ADE) has the advantage of mitigating cross-contamination and reducing cost for high-throughput liquid transfer. The ultrasound transducer design is important for the ADE systems. However, the commonly used systems with single-element focused transducer requires mechanical operation for focusing at different liquid surfaces positions, resulting into low liquid transfer ef...Show More
For the early diagnosis of atherosclerosis and interventions, intravascular ultrasound (IVUS) is a valuable tool for intravascular luminal imaging. Compared with the array-based method, mechanically rotating IVUS catheters dominate the clinical applications because of their less complexity and better suitability for high-frequency ultrasound imaging. However, mechanically rotating catheters are su...Show More
High-definition intravascular ultrasound (HD-IVUS) utilizing more than 80 MHz frequency to assess atherosclerotic plaque, can theoretically achieve an axial resolution of less than $20~\mu \text{m}$ . However, the blood is a high-attenuation source at high frequency, which would affect the imaging quality. There has been no research evaluating the blood-induced influence on HD-IVUS imaging. And w...Show More
Missing values, diversified data types and insufficient sample size have become obstacles to clinical data analysis. In this work, we proposed a machine learning pipeline to analyze the metastasis rate of papillary thyroid carcinoma using B mode ultrasound images and incomplete clinical features simultaneously. Missing values in the clinical features were imputed by the multiple imputation algorit...Show More
Ultrasound (US) brain stimulation is a promising treatment for epilepsy. However., the mechanism of how US suppresses seizures is unclear. Most of the preclinical tests were performed on anesthetic animals, which limits the accurate assessment of US suppression. In this study, we applied transcranial US with different stimulation paradigms on awake epileptic mice models induced by pentylenetetrazo...Show More
Noninvasive ultrasound (US) brain therapies, including US brain stimulation, US drug delivery by BBB opening, or US thrombolysis, have great potential in clinical applications. But target positioning is a challenge. Dual-mode US system provides a promising solution, which can carry out US therapy function under the guidance of US imaging. However, the brain skull usually deteriorates the brain ima...Show More
Coherent focused wave compounding (CFWC) has been adopted widely in high-end commercial ultrasound scanner to improve the image quality, although its name differs in different companies. In CFWC, each image line is coherently compounded by several focused waves. However, CFWC image would get worse like all other compounding techniques when imaging a rapid moving tissue such as cardiac. The convent...Show More
Synthetic transmit aperture (STA) can achieve very high spatial resolution thanks to its dynamic focusing in both transmit and receive. However, because each element is activated individually and sequentially to transmit a spherical wave, the imaging frame rate is low. In addition, the low transmitted energy leads to low signal-to-noise ratio (SNR) echoes. In our previous study, we proposed to use...Show More
Ultrasound contrast agent microbubbles are considered promising sensors to measure portal vein pressure noninvasively. In this study, we investigated the subharmonic scattering power and optimal incident acoustic pressure of SonoVue microbubbles (concentration: $1~\mu \text{L}$ /mL 0.9% NaCl solution) in the ambient pressure range of 10–40 mmHg with 10-mmHg increments at a temperature of 25 °C. T...Show More
In this letter, the redistribution layer-first embedded fan-out wafer-level packaging (RDL-first FO-WLP) for 2-D ultrasonic transducer arrays with individual electrical connection is proposed. This process provides the capability of manufacturing thin film circuit with multilayer RDLs and allows signals of elements in arrays being fanned-out to a region larger than the array size. An anisotropic c...Show More
Focused ultrasound (FUS) lacks reliable real-time image guidance, which hinders the development of non-invasive ultrasound treatment in many important clinical applications. A dual-mode ultrasound array, capable of both imaging and therapy offers a new and reliable strategy for image-guided ultrasound therapy applications. The strategy has the advantages of real-time use, low cost, portability and...Show More
Acoustic droplet ejection (ADE) uses the acoustic energy produced by a focused ultrasound beam to provide a noncontact, highly precise, automatic, and cost-effective liquid transfer method for life science applications. The reported minimum precision of the current acoustic liquid transfer technology is 1 nL. Since precision improvement always brings valuable results in biological research, it is ...Show More
The emergence of new ultrasound technologies has improved our understanding of the brain functions and offered new opportunities for the treatment of brain diseases. Ultrasound has become a valuable tool in preclinical animal and clinical studies as it not only provides information about the structure and function of brain tissues but can also be used as a therapy alternative for brain diseases. H...Show More
Brain ultrasound has attracted great attention recently due to its noninvasive treatment function for brain diseases. However, ultrasound is still difficult to pass through an intact skull. Phase correction is recognized as an effective method for skull compensation. Half-wavelength pitch transducer is important for the phase correction and, hence, thousands of elements array is required to cover ...Show More
As an adaptive beamforming method, minimum variance beamforming (MV) has been introduced to medical ultrasound imaging to improve the image quality in terms of spatial resolution and contrast resolution. Different from the conventional delay-and-sum (DAS) with a pre-determined apodization, MV is capable of adaptively producing apodization pixel-by-pixel based on the incoming echoes. The key step o...Show More
A two-dimensional (2-D) array with a small pitch (approximately 0.5λ in medium) can achieve complete 3-D control of ultrasound beams without grating lobes and enable the generation of multiple focal spots simultaneously, which is a desired tool for noninvasive therapy. However, the large electrical impedance of 2-D array elements owing to their small size results in a low energy transfer efficienc...Show More
In this work, the development and performance evaluation of a high-frequency miniature ultrasonic transducer based on a Pb(Ni1/3Nb2/3)O3-Pb(Zr0.3Ti0.7)O3(PNN-PZT-based) ceramic for intravascular imaging application are reported. The fabricated PNN-PZT-based ceramic possesses ultrahigh relative clamped dielectric permittivity (εs/ε0 = 3409 and high electromechanical coupling capability (kt= 0.60). ...Show More
This study proposes a catheter consisting of dual-frequency transducer for intravascular ultrasound. Both ultrasonic elements with different frequencies were connected to one coaxial cable to make the connection simple. The aperture sizes of the ultrasound elements were 0.4 × 0.6 and 0.3 × 0.4 mm2 for the low-frequency element and high-frequency element, respectively. The center frequency and band...Show More
Both the morphological anatomy and functional parameters such as flow speed of the artery provide valuable information for the evaluation of cardiovascular diseases. Direct measurement of the arterial wall can be achieved by intravascular optical/ultrasound imaging methods, and however, no functional data are acquired with these methods. Fractional flow reserve and Doppler wire have been used to a...Show More
Neuromodulation is a fundamental method for obtaining basic information about neuronal circuits for use in treatments for neurological and psychiatric disorders. Ultrasound stimulation has become a promising approach for noninvasively inducing neuromodulation in animals and humans. However, the previous investigations were subject to substantial limitations, due to most of them involving anestheti...Show More