Cost-Effective Photoacoustic Imaging Using High-Power Light-Emitting Diodes Driven by an Avalanche Oscillator

Sensors, Год журнала: 2025, Номер 25(6), С. 1643 - 1643

Опубликована: Март 7, 2025

Photoacoustic imaging (PAI) is an emerging modality that merges optical and ultrasound to provide high-resolution functional insights into biological tissues. This technique leverages the photoacoustic effect, where tissue absorbs pulsed laser light, generating acoustic waves are captured reconstruct images. While lasers have traditionally been light source for PAI, their high cost complexity drive interest towards alternative sources like light-emitting diodes (LEDs). study evaluates feasibility of using avalanche oscillator high-power LEDs in a basic system. An oscillator, utilizing semiconductor breakdown produce high-voltage pulses, powers generate short, high-intensity pulses. The system incorporates LED array, ultrasonic transducer, amplifier signal detection. Key findings include successful generation short pulses with sufficient intensity excite materials system’s capability detectable signals both air water environments. demonstrate cost-effectiveness portability advantages, challenges such as lower power broader spectral bandwidth compared noted. results affirm LED-based systems, though currently less advanced than laser-based present promising direction affordable portable technologies.

Язык: Английский

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Development and characterization of transfontanelle photoacoustic imaging system for detection of intracranial hemorrhages and measurement of brain oxygenation: Ex-vivo

Photoacoustics, Год журнала: 2023, Номер 32, С. 100538 - 100538

Опубликована: Июль 27, 2023

We have developed and optimized an imaging system to study improve the detection of brain hemorrhage quantify oxygenation. Since this is intended be used for in neonates through skull opening, i.e., fontanelle, we called it, Transfontanelle Photoacoustic Imaging (TFPAI) system. The terms optical acoustic designs, thermal safety, mechanical stability. lower limit quantification TFPAI detect location its size evaluated using in-vitro ex-vivo experiments. capability measuring tissue oxygenation vasogenic edema due blood barrier disruption are demonstrated. results obtained from our experimental evaluations strongly suggest potential utility TFPAI, as a portable modality neonatal intensive care unit. Confirmation these findings in-vivo could facilitate translation promising technology clinic.

Язык: Английский

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Spiral laser scanning photoacoustic microscopy for functional brain imaging in rats

Neurophotonics, Год журнала: 2024, Номер 11(01)

Опубликована: Фев. 9, 2024

SignificanceThere are many neuroscience questions that can be answered by a high-resolution functional brain imaging system. Such system would require the capability to visualize vasculature and measure neural activity entire continually in rapid succession order capture hemodynamic changes. Utilizing optical excitation acoustic detection, photoacoustic technology enables label-free quantification of changes endogenous chromophores, such as oxyhemoglobin, deoxyhemoglobin, total hemoglobin.AimOur aim was develop sufficiently high-resolution, fast frame-rate, wide field-of-view (FOV) microscopy (PAM) for purpose hemodynamics rat brain.ApproachAlthough most PA systems use raster scanning (or less commonly Lissajous scanning), we have developed simple-to-implement laser resolution PAM with spiral (which named "spiral microscopy" or sLS-PAM) acquire an 18 mm diameter image at frame rate (more than 1 fps). is designed permit continuous without introduction photobleaching artifacts.ConclusionWe demonstrated sLS-PAM cerebral response whisker electrical stimulation used it vascular modeled injury. We believe development system, which could become affordable neuroimaging tool researchers.

Язык: Английский

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Transfontanelle photoacoustic imaging for in-vivo cerebral oxygenation measurement

Scientific Reports, Год журнала: 2022, Номер 12(1)

Опубликована: Сен. 13, 2022

Abstract The capability of photoacoustic (PA) imaging to measure oxygen saturation through a fontanelle has been demonstrated in large animals in-vivo . We called this method, transfontanelle (TFPAI). A surgically induced 2.5 cm diameter cranial window was created an adult sheep skull model the human anterior fontanelle. performance TFPAI evaluated by comparing PA-based predicted results against gold standard blood gas analyzer measurements.

Язык: Английский

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Couplants in Acoustic Biosensing Systems

Chemosensors, Год журнала: 2022, Номер 10(5), С. 181 - 181

Опубликована: Май 9, 2022

Acoustic biosensors are widely used in physical, chemical, and biosensing applications. One of the major concerns acoustic is delicacy medium through which waves propagate reach sensors. Even a small airgap diminishes signal strengths due to high impedance mismatch. Therefore, presence coupling create pathway for an efficient propagation essential. Here, we have reviewed characteristics various material (liquid, gel-based, semi-dry, dry) present guide determine suitable application-specific medium.

Язык: Английский

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Randomized multi‐angle illumination for improved linear array photoacoustic computed tomography in brain

Journal of Biophotonics, Год журнала: 2022, Номер 15(6)

Опубликована: Март 14, 2022

One of the key challenges in linear array transducer-based photoacoustic computed tomography is to image structures embedded deep within biological tissue with limited optical energy. Here, we utilized a manually controlled multi-angle illumination technique allow incident photons interact imaging targets for longer periods time and diffuse further all directions. We have developed optimized compact probe that enables manual changes angle while acquiring signals. The performance has been demonstrated evaluated by complex blood vessel mimicking phantoms in-vitro sheep brain samples ex-vivo. For effective reconstruction from data acquired method, method based on extraction maximum intensity. In both cases, out-performed conventional fixed improve overall quality. Specifically, located at greater axial depths was possible using this technique.

Язык: Английский

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Transfontanelle photoacoustic imaging of intraventricular brain hemorrhages in live sheep

Photoacoustics, Год журнала: 2023, Номер 33, С. 100549 - 100549

Опубликована: Авг. 24, 2023

Intraventricular (IVH) and periventricular (PVH) hemorrhages in preterm neonates are common because the blood vessels still developing up to 36 weeks fragile. Currently, transfontanelle ultrasound (US) imaging is utilized for screening IVH PVH, largely through anterior fontanelle. However mild hemorrhages, inconclusive diagnoses common, leading failure detect IVH/PVH or, when other clinical symptoms present, use of second stage neuroimaging modalities requiring transport vulnerable patients. Yet even increases risk moderate-severe neurodevelopmental impairment. Here, we demonstrate capability photoacoustic (TFPAI) PVH in-vivo a large animal model. TFPAI was able as small 0.3 mL volume brain (p < 0.05). By contrast, US 0.5 mL. These preliminary results suggest could be translated into portable bedside probe improved diagnosis clinically relevant neonates.

Язык: Английский

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Evaluation of 10 current image reconstruction algorithms for linear array photoacoustic imaging

Journal of Biophotonics, Год журнала: 2023, Номер 17(3)

Опубликована: Ноя. 28, 2023

Abstract Various reconstruction algorithms have been implemented for linear array photoacoustic imaging systems with the goal of accurately reconstructing strength absorbers within tissue being imaged. Since existing introduced by different research groups and context performance evaluation was not consistent, it is difficult to make a fair comparison between them. In this study, we systematically compared 10 published image (DAS, UBP, pDAS, DMAS, MV, EIGMV, SLSC, GSC, TR, FD) using in‐vitro phantom data. Evaluations were conducted based on lateral resolution reconstructed images, computational time, target detectability, noise sensitivity. We anticipate outcome study will assist researchers in selecting appropriate their PA applications.

Язык: Английский

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Assessment of a Single‐Element Scanning System for Enhanced Photoacoustic Imaging of Brain Hemorrhage

Journal of Biophotonics, Год журнала: 2025, Номер unknown

Опубликована: Янв. 13, 2025

The use of photoacoustic brain imaging for hemorrhage detection holds significant clinical importance. This study focuses on the performance sensitivity and capabilities a single-element scanning system, considering remarkable signal-to-noise ratio signals generated by transducer. By employing blood vessel-like phantoms ex vivo phantoms, we demonstrated superior efficacy method over transducer array system in context detection. research highlights potential enhancing through careful design optimization proposed method, thereby increasing its viability application.

Язык: Английский

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Utility of Low-Cost Multichannel Data Acquisition System for Photoacoustic Computed Tomography

Photonics, Год журнала: 2025, Номер 12(4), С. 385 - 385

Опубликована: Апрель 16, 2025

Typically, multi-single-element photoacoustic computed tomography (PACT) systems utilize numerous ultrasound transducers arranged in cylindrical or hemispherical configurations for detection, combined with a single diffuse light source multiple sparse sources to illuminate the imaging target. While these produce high-quality 3D PA images, they require complex, multi-channel data acquisition (DAQ) acquire from all transducers. These DAQ are often bulky and expensive, significantly limiting clinical translation of PACT patient care. In this study, we evaluated feasibility using compact cost-effective Texas Instruments analog front-end module systems. By simple phantom, demonstrated capability affordable board, reconstructed images showing promise practical economical solutions This advancement paves way broader applications both research settings.

Язык: Английский

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