Diffuse optical tomography is an imaging technique whereby spatial maps of absorption and scattering coefficients are derived from the characteristics multiply scattered light transmitted through object. The system described here used four intensity-modulated sources measurements intensity phase (relative to each source) at 16 or 20 detectors on surface a 10 cm diameter cylinder. An iterative Newton-Raphson algorithm was estimate pixel in 17*17 array minimizing difference between measured...

Hummers method is commonly used for the fabrication of graphene oxide (GO) from graphite particles. The oxidation process also leads to cutting sheets into small pieces. From a thermodynamic perspective, it seems improbable that aggressive, somewhat random oxidative could directly result in nanosheets without destroying intrinsic π-conjugated structures and associated exotic properties graphene. In method, both KMnO4 NO2+ (nitronium ions) concentrated H2SO4 solutions act as oxidants via...

The use of photoacoustic effect is a promising approach for biomedical imaging in living tissues. Photoacoustic tomography (PAT) has been demonstrated to image breast cancer, brain vasculature, arthritis and seizure focus owing its rich optical contrast high resolution single modality. Here we report microelectromechanical systems (MEMS)-based intraoperative PAT (iPAT) technique, demonstrate ability accurately map tumors three-dimension inspect the completeness tumor resection during surgery...

Self-powered wearable electronics to convert mechanical and thermal energy into electrical are important for biomedical monitoring, which highly require good flexibility, comfortability, signal sensitivity, accuracy. In this work, composite nanofiber mats of polyacrylonitrile (PAN) trimethylamine borane (TMAB) were prepared by electrospinning, exhibited excellent piezoelectric pyroelectric abilities in harvesting energy. The PAN/TMAB-4 not only generated a high voltage up 2.56 V power 0.19...

We present a new method that can provide high resolution images of absolute optical absorption coefficient in heterogeneous turbid media. In this method, acoustic measurements conventional photoacoustic tomography are combined with diffusing light to separate the product and fluence or photon density. validate using series tissuelike phantom experiments. The experimental results show targets as small 0.5 mm diameter contrasts low 1.5 relative 50 scattering background medium be clearly detected.

We describe a novel reconstruction method that allows for quantitative recovery of optical absorption coefficient maps heterogeneous media using tomographic photoacoustic measurements. Images are obtained from diffusion equation based regularized Newton where the absorbed energy density distribution conventional tomography serves as measured field data. experimentally demonstrate this new tissue-mimicking phantom measurements and simulations. The results show images in terms shape, size,...

Multimodal Gold-speckled silica nanoparticles as contrast agents for noninvasive imaging with magnetic resonance and photoacoustic tomography have been prepared in a simple one-pot synthesis using nonionic microemulsions. Magnetic is provided through gadolinium incorporated the matrix, whereas signal originates from nonuniform, discontinuous gold nanodomains speckled across surface.

We report on experimental demonstration of thermoacoustic tomography for quantitatively reconstructing the conductivity images heterogeneous media. Thermoacoustic are obtained from a series tissue-like phantom experiments using finite element-based reconstruction algorithm coupled with scanning imaging system. The results show that can be reconstructed based finite-element (FE) solution to Helmholtz electromagnetic wave equation equation.

We report on the fabrication of a piezoelectric micromachined ultrasonic transducer (pMUT) and its application to photoacoustic imaging. With c-axis orientation, AlN was grown 300 nm-thick SiO2 film 200 bottom electrode at room temperature. The device consists SiO2, electrode, films, upper polyimide protective layer. An area ratio 0.45 used between vibration pMUT provide an optimal sensitivity transducer. Its resonant frequency measured be 2.885 MHz, coupling coefficient in range...

We present a noninvasive method of photoacoustic tomography (PAT) for imaging cerebral hemodynamics in awake-moving rats. The wearable PAT (wPAT) system has size 15 mm height and 33 diameter, weight ~8 g (excluding cabling). wPAT achieved an rate 3.33 frames/s with lateral resolution 243 μm. Animal experiments were designed to show feasibility on animals. Results showed that the oxy-hemoglobin deoxy-hemoglobin changed significantly response hyperoxia; and, after injection pentylenetetrazol...

Purpose: Both photoacoustic tomography (PAT) and fluorescence molecular (FMT) can be used for imaging when contrast agents are administrated. The goal of this work is to comparatively evaluate the performance reflection‐mode PAT FMT in common phantom indocyanine green (ICG) was as a agent. Methods: Reflection‐mode systems were developed. Target embedded background with different ICG concentration, size, depth location examined. Comparisons made terms target morphology, spatial resolution,...

Purpose: To evaluate the feasibility of functional photoacoustic tomography (fPAT) for high resolution detection and characterization breast cancer to demonstrate first time quantitative hemoglobin concentration oxygen saturation images breasts that were formed with model‐based reconstruction tomographic data. Methods: The study was HIPAA compliant approved by university institutional review board. Written informed consents obtained from all participants. Ten cases, including six four...

A single miniature endoscope capable of concurrently probing multiple contrast mechanisms tissue in high resolution is highly attractive, as it makes possible for providing complementary, more complete information on internal organs hard to access. Here we describe such a only 1 mm diameter that integrates photoacoustic imaging (PAI), optical coherence tomography (OCT), and ultrasound (US). The integration PAI/OCT/US allows high-resolution three contrasts including absorption scattering...

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Objective:</i> the purpose of this study was to demonstrate potential thermoacoustic tomography (TAT) reveal anatomic structures xmlns:xlink="http://www.w3.org/1999/xlink">in vivo</i> human finger joints. xmlns:xlink="http://www.w3.org/1999/xlink">Methods:</i> all participating volunteers provided written informed consent. Eight healthy middle and index fingers from five were imaged by our TAT...

Photoacoustic imaging (PAI) has emerged as a transformative modality for bridging traditional Chinese medicine (TCM) theory and contemporary biomedical research in acupuncture mechanism studies. This review assesses PAI’s capacity to decode acupuncture-induced neuromodulatory hemodynamic effects, with dual focus on the central nervous system (CNS) responses acupoint-specific microcirculatory dynamics. Leveraging photoacoustic effect coupled ultrasonic detection, PAI enables non-invasive,...

We report on experimental demonstration of photoacoustic tomography for simultaneous recovery the optical and acoustic properties heterogeneous media. Photoacoustic images are reconstructed from a series tissue-like phantom experiments using finite element-based reconstruction algorithm coupled with scanning imaging system. The results show that obtained quantitative in terms shape, size, location heterogeneities examined.

We describe a method that combines fluorescence molecular tomography (FMT) with diffuse optical (DOT), which allows us to study the impact of heterogeneous property distribution on FMT, an issue has not been systemically studied. Both numerical simulations and phantom experiments were performed based our finite-element reconstruction algorithms. The conducted using noncontact fiber free, multiangle transmission system. In both experiments, fluorescent target was embedded in optically...

Microwave-induced thermoacoustic tomography (MI-TAT) is an imaging modality that exploits dielectric contrast while producing images with high ultrasound resolution. Existing reconstruction algorithms for MI-TAT are qualitative and can image only the distribution of absorbed microwave energy or power loss density. Here authors describe a method quantitative obtain property which directly correlates tissue structural functional information.The implement based on finite-element (FE) solution...

Purpose: The purpose of this pilot clinical study is to assess three‐dimensional (3‐D) quantitative photoacoustic tomography (qPAT) for in vivo detection osteoarthritis (OA) the finger joints. Methods: All subject data were handled compliance with rules and regulations concerning privacy security protected health information under HIPAA. Seven female subjects (two OA patients five healthy controls) entered their distal interphalangeal (DIP) joints examined by a 3‐D scanner. optical...

In this Letter, we present a novel tri-modal miniature side-view probe, through which optical-resolution photoacoustic microscopy (OR-PAM), optical coherence tomography (OCT), and pulse-echo ultrasound (US) images can be coaxially acquired displayed simultaneously. The probe consists of common path for OR-PAM (light delivery) OCT delivery/detection), 40-MHz unfocused transducer (photoacoustic detection) US (ultrasound transmission/receiving) with an overall diameter 2 mm. Combining OR-PAM,...

Abstract Miniaturized ultrasonic transducer arrays with multiple frequencies are key components in endoscopic photoacoustic imaging (PAI) systems to achieve high spatial resolution and large depth for biomedical applications. In this article, we report on the development of ceramic thin-film PZT-based dual- multi-frequency piezoelectric micromachined (pMUT) demonstration their PAI With chips sized 3.5 mm length or 10 diameter, square ring-shaped pMUT incorporating as many 2520 elements...

The <i>Journal of Biomedical Optics</i> (JBO) is a Gold Open Access journal that publishes peer-reviewed papers on the use novel optical systems and techniques for improved health care biomedical research.