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...

In this Letter, we present a photoacoustic imaging (PAI) system based on low-cost high-power miniature light emitting diode (LED) that is capable of in vivo mapping vasculature networks biological tissue. Overdriving with 200 ns pulses and operating at repetition rate 40 kHz, 1.2 W 405 nm LED radiation area 1000 μm×1000 μm size 3.5 mm×3.5 mm was used to excite signals Phantoms including black stripes, lead, hair were validate the which volumetric PAI image obtained by scanning transducer...

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...

We describe a novel dual-modality imaging approach that integrates diffuse optical tomography (DOT) and photoacoustic (PAI) through miniaturized handheld probe based on microelectromechanical systems (MEMS) scanning mirror. validate this dual-modal DOT/PAI using extensive phantom experiments, demonstrate its application for tumor tumor-bearing mice systematically injected with targeted contrast agents.

In this paper, we present the design, fabrication, and characterization of a compact 4 × piezoelectric micromachined ultrasonic transducer (pMUT) array its application to photoacoustic imaging. The uniqueness pMUT is integration μm-thick ceramic PZT, having significantly higher coefficient lower stress than sol-gel or sputtered PZT. fabricated has small chip size only 1.8 1.6 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> with each...

In epilepsy it has been challenging to detect early changes in brain activity that occurs prior seizure onset and map their origin evolution for possible intervention. Here we demonstrate using a rat model of generalized diffuse optical tomography (DOT) provides unique functional neuroimaging modality noninvasively continuously tracking such activities with high spatiotemporal resolution. We detected hemodynamic responses heterogeneous patterns, along intracranial electroencephalogram gamma...

Advances in epilepsy studies have shown that specific changes hemodynamics precede and accompany seizure onset propagation. However, it has been challenging to noninvasively detect these real time humans, due the lack of fast functional neuroimaging tools. In this study, we present a diffuse optical tomography (DOT) method with guidance an anatomical human head atlas for 3‐dimensionally mapping brain time. Central our DOT system is interface coupled technique can incorporate topological...

This paper presents a dual-frequency piezoelectric micromachined ultrasonic transducer (pMUT) array based on thin ceramic PZT for endoscopic photoacoustic imaging (PAI) applications. With chip size of 7 × mm2, the pMUT consists 256 elements, half which have lower resonant frequency 1.2 MHz and other higher 3.4 MHz. Ceramic PZT, with outstanding coefficients, has been successfully thinned down to thickness only 4 μ by using wafer bonding chemical mechanical polishing (CMP) techniques employed...

Functional neuroimaging studies of neuropsychiatric disorders and cognitive impairment are commonly conducted in the clinic setting but less so acutely medically ill while hospitalized. This is largely due to technical logistical limitations, given lack portable devices with high spatial temporal resolutions. exploratory study reports on development implementation a novel diffuse optical tomography (DOT) system that can be employed for bedside three-dimensional functional neuroimaging. To...

Abstract INTRODUCTION Delirium is associated with mortality and new onset dementia, yet the underlying pathophysiology remains poorly understood. Development of imaging biomarkers has been difficult given challenging nature delirious patients. Diffuse optical tomography (DOT) offers a promising approach for investigating delirium its portability three‐dimensional capabilities. METHODS Twenty‐five matched non‐delirious patients ( n = 50) were examined using DOT, comparing cerebral oxygenation...

We describe a multispectral continuous-wave diffuse optical tomography (DOT) system that can be used for in vivo three-dimensional (3-D) imaging of seizure dynamics. Fast 3-D data acquisition is realized through time multiplexing approach based on parallel lighting configuration--our achieve 0.12 ms per source wavelength and up to 14 Hz sampling rate full set DOT image reconstruction. The validated using both static dynamic tissue-like phantoms. An initial experiment rat model also demonstrated.

This paper presents a piezoelectric micromachined ultrasonic transducer (pMUT) array fabricated using high-piezoelectric-coefficient ceramic PZT wafers. A new process for polishing layers down to 5 μm has been developed and applied manufacturing high-sensitivity pMUTs. 2 MHz working pMUT (8 × 8 elements) based on designed, modeled, characterized.

A tubular lattice nodeless hollow core photonic crystal fiber (NHC-PCF) with unsymmetrical gap design is proposed. The relies on one large between the cladding tubes and aligned a slot running down entire length of fiber. special NHC-PCF will bring great convenience for its optofluidic applications also facilitate drawing process or microcutting postprocess without resulting in operation difficulties extra principle loss, making it useful platform gas sensing other applications. We have...

This paper presents, for the first time, a multifrequency piezoelectric micromachined ultrasonic transducer (pMUT) array endoscopic photoacoustic imaging applications. With chip size of 3.5 × mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , pMUT consists 285 elements with seven different resonant frequencies ranging from 1 MHz to 8 MHz. The has been fabricated on 9 µm-thick layer ceramic PZT high constants. Mechanical vibration tests...

Abstract Distorted urea levels indicate several liver, kidney, or metabolic diseases; however, traditional clinical detection relies on urease‐based methods enslaved to well‐known limitations of high‐price, unstable properties, complicated sample pretreatment and analysis procedures, difficult visual real‐time monitoring. Herein, nonenzymatic paper‐based fluorescent materials (UFP‐BP) are strategically integrated with an on‐demand fluorescent‐sensor (UFP) self‐aggregated nanoparticle...

Summary Objective The goal of this work is to establish a new dual‐modal brain‐mapping technique based on diffuse optical tomography ( DOT ) and electroencephalographic source localization ESL that can chronically/intracranially record optical/electroencephalography EEG data precisely map seizures localize the seizure‐onset zone associated epileptic brain network. Methods imaging system was employed image in an experimental acute bicuculline methiodide rat model focal epilepsy. Depth...

A transmission and reflection coupled ultrasonic process tomography has been developed, which is characterized by a proposed dual-mode (DM) reconstruction algorithm, as well an adaptive search approach to determine optimal image threshold during the binarization. In respect of hardware, improve accuracy time-of-flight (TOF) extend lowest detection limit particle size, cylindrical miniaturized transducer using polyvinylidene fluoride (PVDF) films designed. Besides, development range-gating...

In the article, a combination by two all-optical XOR/XNOR logic gates using photonic crystal for binary-phase-shift-keyed (BPSK) signals and AND gate intensity modulation is proposed. The novel NOR BPSK are realized. Finite-difference-time-domain (FDTD) scheme applied. numerical results indicate that contrast specific value of 1 0 logic-levels more than 21dB operation 19dB over C-band (1530-1565nm).

The influence of transverse mode were researched with the injection current changing via experiments conducted 980nm oxide-confined vertical cavity surface emitting lasers (VCSELs). Based on spatio-temporal rate equation, parameter dependence characteristics weak-index guiding VCSELs theoretically by integrating spatially dependent part. result experiment indicated that higher-order modes begin to emerge and exhibit strong competition increased when oxidized aperture was kept unchanged,...

We present a photoacoustic imaging system based on low-cost high-power miniature light emitting diode (LED), which has the capability of in vivo mapping vasculature networks biological tissue. Phantoms were used to demonstrate feasibility system, while mouse ear shows that LED-based (LED-PAI) could have great potential for label-free biomedical applications, overcoming practical limitations use bulky and expensive pulsed lasers.

We present a novel FMT endoscope by using MEMS scanning mirror and an optical fiberscope. The diameter of this highly miniaturized device is only 5 mm. To our knowledge, the smallest we found so far. Several phantom experiments based on indocyanine green (ICG) were conducted to demonstrate imaging ability device. Two tumor-bearing mice systematically injected with tumor-targeted NIR fluorescent probes (ATF-PEG-IO-830) then imaged further for small animals.