Photoacoustic signal generation by metal nanoparticles relies on the efficient conversion of light to heat, its transfer environment, and production pressure transients. In this study we demonstrate that a dielectric shell has strong influence amplitude generated photoacoustic silica-coated gold nanorods same optical density are capable producing about 3-fold higher signals than without silica coating. Spectrophotometry measurements finite difference time domain (FDTD) analysis before after...

Photothermal stability and, therefore, consistency of both optical absorption and photoacoustic response the plasmonic nanoabsorbers is critical for successful image-guided photothermal therapy.In this study, silica-coated gold nanorods were developed as a multifunctional molecular imaging therapeutic agent suitable therapy.The properties under intense irradiation with nanosecond laser pulses investigated by UV-Vis spectroscopy transmission electron microscopy.Silica-coated showed increased...

Compressive 3D ultrasound imaging is possible with only one sensor and a simple aperture coding mask.

Oncological neurosurgery relies heavily on making continuous, intra-operative tumor-brain delineations based image-guidance. Limitations of currently available imaging techniques call for the development real-time image-guided resection tools, which allow reliable functional and anatomical information in an setting. Functional ultrasound (fUS), is a new mobile neuro-imaging tool with unprecedented spatiotemporal resolution, allows detection small changes blood dynamics that reflect metabolic...

Current clinical ultrasound scanners cannot be used to image the interior morphology of bones because these fail address complicated physics involved for exact reconstruction. Here, we show that if is properly addressed, bone cortex can imaged using a conventional transducer array and programmable scanner. We provide in vivo proof this technique by scanning radius tibia two healthy volunteers comparing thickness with high-resolution peripheral x-ray computed tomography. Our method assumes...

Previously, pulsed magneto-motive ultrasound (pMMUS) imaging has been introduced as a contrast-agent-assisted ultrasound-based modality capable of visualizing biological events at the cellular and molecular level. In pMMUS imaging, high intensity magnetic field is used to excite cells or tissue labeled with nanoparticles. Then, (US) monitor mechanical response an externally applied (i.e., displacement). Signal noise ratio (SNR) in can be improved by using superparamagnetic nanoparticles...

Beamforming of plane-wave ultrasound echo signals in the Fourier domain provides fast and accurate image reconstruction. Conventional implementations perform a k-space interpolation from uniform sampled grid to nonuniform acoustic dispersion grid. In this paper, we demonstrate that step can be replaced by transform. We study performance transform (NUFFT) terms signal-to-noise ratio computational cost, show NUFFT offers an advantage trade-off between speed accuracy, compared with other...

We introduce a method for photoacoustic imaging of the carotid artery, tailored toward detection lipid-rich atherosclerotic lesions. A common human artery was obtained at autopsy, embedded in neck mimicking phantom and imaged with multimodality system using interstitial illumination. Light delivered through 1.25-mm-diameter optical probe that can be placed pharynx, allowing to illuminated from within body. Ultrasound signal is achieved by an external 8-MHz linear array coupled ultrasound...

Abstract Background We aimed to describe the microvascular features of three types adult-type diffuse glioma by comparing dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI) with intraoperative high-frame-rate ultrafast Doppler ultrasound. Methods Case series seven patients primary brain tumours underwent both DSC MRI and intra-operative From ultrasound images, three-dimensional vessel segmentation was obtained tumour vascular bed. Relative cerebral blood volume...

In interventional electrophysiology, catheter-based radiofrequency (RF) ablation procedures restore cardiac heart rhythm by interrupting aberrant conduction paths. Real-time feedback on lesion formation and post-treatment assessment could overcome procedural challenges related to of underlying structures gaps. This study aims evaluate real-time visualization progression continuity during intra-atrial with photoacoustic (PA) imaging, using clinically deployable technology. A PA-enabled RF...

Four-dimensional ultrasound imaging of complex biological systems such as the brain is technically challenging because spatiotemporal sampling requirements. We present computational (cUSi), an method that uses fields can be generated with simple hardware and a physical wave prediction model to alleviate constraints. cUSi allows for high-resolution four-dimensional hemodynamics in awake anesthetized mice.

This paper presents an ultrasound transceiver application-specific integrated circuit (ASIC) designed for 3-D ultrasonic imaging of the carotid artery. application calls array thousands transducer elements, far exceeding number channels conventional systems. The 3.6 × 6.8 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ASIC interfaces a piezo-electric (PZT) 24 40 directly on top ASIC, to system using only transmit and receive...

Ultrasonography could allow operator-independent examination and continuous monitoring of the carotid artery, but normally requires complex expensive transducers, especially for 3D. By employing computational ultrasound imaging (cUSi), using an aberration mask model-based reconstruction, a device be constructed with more affordable simple transducer design comprising only few elements. We aim to apply cUSi concept create artery system. The system's possible configurations 2D case were...

Ultrafast Doppler ultrasound imaging allows for detailed images of blood flow inside the brain during neurosurgical interventions. In this work, we extend new technique to geometrically accurate volumetric reconstructions using freehand 2D ultrafast acquisitions in conjunction with optical position tracking. We show how signal can be derived from a moving scan. These filtered are subsequently mapped onto shared 3D reference space normalized convolution function. The proposed methodology...

Echocardiographic determination of multicomponent blood flow dynamics in the left ventricle remains a challenge. In this paper, we compare contrast enhanced, high frame rate (HFR) (1000 frames/s) echo-particle image velocimetry (ePIV) against optical particle (oPIV, gold standard), realistic ventricular (LV) phantom. We find that ePIV compares well to oPIV, even for velocity inflow jet (normalized RMSE = 9% ± 1%). addition, perform method proper orthogonal decomposition, better qualify and...

Catheter-based radiofrequency ablation for atrial fibrillation has long-term success in 60-70% of cases.A better assessment lesion quality, depth, and continuity could improve the procedure's outcome.We investigate here photoacoustic contrast between ablated healthy atrial-wall tissue vitro wavelengths spanning from 410 nm to 1000 nm.We studied single-and multi-wavelength imaging lesions we demonstrate that a two-wavelength technique yields precise detection lesions, achieving diagnostic...

We present a form of acoustic microscopy, called Structured Ultrasound Microscopy (SUM). It creates volumetric image by recording reflected echoes ultrasound waves with structured phase front using moving single-element transducer and computational reconstruction. A priori knowledge the field produced single element allows us to relate received 3D scatter map within beam itself, leading an isotropic resolution at all depths. An aberration mask in imposes structure, broadening breaking...

Surgical resection of spinal cord hemangioblastomas remains a challenging endeavor: the neurosurgeon's aim to reach total tumor resections directly endangers their minimize post-operative neurological deficits. The currently available tools guide intra-operative decision-making consist mostly pre-operative imaging techniques such as MRI or MRA, which cannot cater changes in field view. For while now, surgeons have adopted ultrasound and its submodalities Doppler CEUS techniques, given many...