Neuroimaging modalities such as MRI and EEG are able to record from the whole brain, but this comes at price of either limited spatiotemporal resolution or sensitivity. Here, we show that functional ultrasound imaging (fUS) brain is assess local changes in cerebral blood volume during cognitive tasks, with sufficient temporal measure directional propagation signals. In two macaques, observed an abrupt transient change supplementary eye field (SEF) activity when animals were required modify...

3D functional imaging of the whole brain activity during visual task is a challenging in rodents due to complex tri-dimensional shape involved regions and fine spatial temporal resolutions required reveal tract. By coupling ultrasound (fUS) with translational motorized stage an episodic stimulation device, we managed accurately map recover cortices, Superior Colliculus (SC) Lateral Geniculate Nuclei (LGN) 3D. Cerebral Blood Volume (CBV) responses stimuli were found be highly correlated...

Deep regions of the brain are not easily accessible to investigation at mesoscale level in awake animals or humans. We have recently developed a functional ultrasound (fUS) technique that enables imaging hemodynamic responses visual tasks. Using fUS on two nonhuman primates performing passive fixation task, we constructed retinotopic maps depth cortex (V1, V2, and V3) calcarine lunate sulci. The could be acquired single-hour session with relatively few presentations stimuli. spatial...

Objective To develop a quantitative ultrasound (QUS)- and elastography-based model to improve classification of steatosis grade, inflammation fibrosis stage in patients with chronic liver disease comparison shear wave elastography alone, using histopathology as the reference standard. Methods This ancillary study prospective institutional review-board approved included 82 non-alcoholic fatty disease, hepatitis B or C virus, autoimmune hepatitis. Elastography measurements, homodyned...

Change in viscoelastic properties of biological tissues may often be symptomatic dysfunction that can correlated with tissue pathology. Shear wave (SW) elastography is an imaging method mainly used to assess stiffness but the potential measure viscoelasticity tissues. This enable characterization and, thus, as a marker improve diagnosis pathological lesions. In this study, frequency-shift method-based framework presented for reconstruction viscosity by analyzing spectral acoustic radiation...

Photoacoustic imaging can achieve high-resolution three-dimensional (3-D) visualization of optical absorbers at penetration depths ∼1 cm in biological tissues by detecting optically induced high ultrasound frequencies. Tomographic acquisition with linear arrays offers an easy implementation single-side access, parallelized, and high-frequency detection, but usually comes image quality impaired the directionality detectors. Indeed, a simple translation array perpendicular to its median plane...

Attenuation maps or measurements based on the local attenuation coefficient slope (ACS) in quantitative ultrasound (QUS) have shown potential for diagnosis of liver steatosis. In cancers, tissue abnormalities and tumors detected using ACS are also interest to provide new image contrast clinicians. Current phantom-based approaches limitation assuming a comparable speed sound between reference phantom insonified tissues. Moreover, these methods present inconvenience operators acquire data...

Ultrasound noninvasive vascular elastography (NIVE) has shown its potential to measure strains of carotid arteries predict plaque instability. When two-dimensional (2D) strain estimation is performed, either in longitudinal or cross-sectional view, only in-plane motions are considered. The elevation direction (i.e. perpendicular the imaging plane), can induce artifacts affecting accuracy 2D NIVE. influence such out-of-plane on performance axial and shear estimations been evaluated this...

In the field of quantitative ultrasound (QUS), constructing semantic parametric maps based on local attenuation coefficient slope (ACS) or backscatter (BSC) modeling remains a challenge. These may be useful for detecting lesions anatomical objects, characterizing anomalies within organs. The objective was to propose methodology regularized in case linear fitting models. proposed method tested on: i) spectral Gaussian fit (SGF) BSC model, comprising acoustical concentration and effective...

Large-scale functional imaging techniques are part of a fast growing field neuroscience aiming at understanding whole brain activity. The recently introduced Functional Ultrasound Imaging (fUS), based on ultrafast Doppler, is new very sensitive method monitoring changes in slow blood flow with high spatial (~100μm) and temporal (down to the cardiac time scale) resolution for typical imaged section 15mm wide 20mm deep (at 15MHz, animal studies), which makes it an unequalled modality landscape...

Chronic liver disease (CLD) is a highly prevalent condition characterized by the coexistence of histopathological changes, including steatosis, inflammation and fibrosis. Based on multi-parametric approach, goal was to assess ancillary value quantitative US (QUS) parameters point shear-wave elastography (pSWE), based random forests, cohort subjects with CLD. Ninety-one individuals were recruited in this prospective institutional review board approved study, 82 patients included after...

Summary Deep regions of the brain are not easily accessible to investigation at mesoscale level in awake animals or humans. We have recently developed functional Ultrasound (fUS) imaging fUS technique uncover deep hemodynamic responses. Applying on two non-human primates performing a passive fixation task, we reconstructed their retinotopic maps down calcarine and lunate sulci visual areas (V1, V2 V3). These were acquired single hour session with very few stimuli presentation. The spatial...

The spatiotemporal study of the visual system rodent is a challenging area that conventional functional imaging modalities, despite fundamental achievements, still struggle to nowadays. In other hand Functional Ultrasound (fUS) offers an unprecedented combination resolution. By coupling fUS with adapted stimulation device, we mapped vision-evoked activity in brain. We then optimized visual-stimulus toward pathway using fUS.

ABSTRACT In recent decades, neuroimaging has played an invaluable role in improving the fundamental understanding of brain. At macro scale, modalities such as MRI, EEG, and MEG, exploit a wide field view to explore brain global network interacting regions. However, this comes at price either limited spatiotemporal resolution or sensitivity. micro electrophysiology is used dynamic aspects neuronal activity with very high temporal resolution. modality requires statistical averaging several...

Changes in viscoelastic properties of biological tissues may be symptomatic a dysfunction that can correlated to tissue pathology. Past magnetic resonance imaging studies suggest tumors have higher viscosity than normal tissues, and fatty organs might also correlate with viscosity. In this study, frequency-shift method compute attenuation was utilized reconstruct maps by analyzing spectral induced shear waves. The feasibility reconstructions animal samples is investigated. Experiments were...

Noninvasive vascular strain imaging under conventional line-by-line scanning has a low frame rate and lateral resolution depends on the coordinate system. It is thus affected by high deformations due to image decorrelation between frames.To develop an ultrafast time-ensemble regularized tissue-Doppler optical-flow principal estimator for aorta deformability assessment in long-axis view.This approach alleviated impact of using compounding that system dependency strain. Accuracy feasibility...

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Multi-parametric ultrasound imaging is a promising tool for quantification of nonalcoholic fatty liver disease. In this work, protocol plane wave quantitative (QUS) and shear elastography (SWEI), quasi-simultaneously acquired, dedicated to the steatosis on in vivo duck livers presented. Shear velocity was estimated classify stiffness tissues. QUS consisted local attenuation coefficient slope with spectral log difference method, coherent-to-diffuse signal ratio computed from homodyned-K...