Development of a thermoacoustic imaging system to image blood in the brain: preliminary ex-vivo results DOI
Md Tarikul Islam, Juliana Benavides, Ravi Prakash

и другие.

Photons Plus Ultrasound: Imaging and Sensing 2021, Год журнала: 2024, Номер unknown, С. 96 - 96

Опубликована: Фев. 26, 2024

Thermoacoustic imaging (TAI) is a promising new technology for biomedical diagnostics. It combines the high contrast of electromagnetic absorption with resolution ultrasound imaging. Traditional TAI systems use circular scanning modes single or arc detectors, which can be slow and inefficient body scanning. A linear-array detector, commonly used in medical systems, to scan biological tissues more efficiently. In this study, we developed novel system (LATIS) detection hemorrhage brain through fontanelle neonates. The LATIS uses transducer multiple elements, enables rapid data acquisition real-time custom-designed trigger mechanism synchronizes microwave signal generation process, ensuring accurate timing optimal image quality. We evaluated performance by conducting several ex-vivo sheep different amounts artificially induced blood. was able successfully detect lower grades intraventricular hemorrhages experiments. These results demonstrate potential clinical neonates as they are vulnerable hemorrhage.

Язык: Английский

Spiral laser scanning photoacoustic microscopy for functional brain imaging in rats DOI Creative Commons
Mohsin Zafar, Laura Stone McGuire, Seyed Mohsen Ranjbaran

и другие.

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

Процитировано

7
Evaluation of 10 current image reconstruction algorithms for linear array photoacoustic imaging DOI Creative Commons

Ravi Prakash,

Rayyan Manwar, Kamran Avanaki

и другие.

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

Процитировано

9
Assessment of a Single‐Element Scanning System for Enhanced Photoacoustic Imaging of Brain Hemorrhage DOI Creative Commons
Juliana Benavides,

Ravi Prakash,

Kamran Avanaki

и другие.

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

Процитировано

0
Side-Illuminating Optical Fiber for High-Power-Density-Mediated Intraluminal Photoacoustic Imaging DOI Creative Commons
Nidhi Singh, Carlos-Felipe Roa, Emmanuel Chérin

и другие.

Applied Sciences, Год журнала: 2025, Номер 15(7), С. 3639 - 3639

Опубликована: Март 26, 2025

Intraluminal photoacoustic (PA) imaging has the potential for providing physiological and functional information in wide-ranging clinical applications. Along with endoluminal ultrasound transducers, these applications require compact light delivery devices which can deliver high-energy ns-pulsed laser to target region. In this work, we describe design, method of fabrication characterization a new compact, side-fire optical fiber that pulses PA imaging. Side-fire illuminators were fabricated using UV ablation create windows on side 1.5 mm diameter single core, multi-mode reflective silver coating beveled end. Devices 10 mm, 20 30 window lengths their beam profiles characterized. Elongated fibers −6 dB size up 30.79 × 5.5 developed. A total output ratio 0.69 fire efficiency 40%, relative standard front-fire fiber, achieved. We evaluated effects propagation by coupling 18 mJ or 100 MW/cm2 (at 750 nm) from Q-switched laser. The was demonstrated detecting India ink targets embedded chicken breast tissue over full length illumination 100° angle visualizing vivo rat ear vasculature.

Язык: Английский

Процитировано

0
Photoacoustic Microscopy for Studying Mechano-transduction Response in Resistance Vessels DOI Creative Commons
Juliana Benavides,

Dianicha Santana Nunez,

Mohsin Zafar

и другие.

Photoacoustics, Год журнала: 2025, Номер unknown, С. 100713 - 100713

Опубликована: Апрель 1, 2025

Cardiovascular diseases are on the rise, presenting a significant global health challenge. The development of methods enabling detection alterations in vascular networks is critical for early diagnosis and treatment cardiovascular diseases, including peripheral arterial disease, stroke, hypertension. Here, we use photoacoustic microscopy (PAM), non-invasive imaging technique, to monitor morphological changes within skin vessels chronically hypertensive mice deficient mechanosensitive channel Piezo1 endothelial cells (Piezo1 EC-KO). We show that, compared control flox/flox), EC-KO characterized by poorer tissue perfusion due vasoconstriction resistance arterioles. also effect administration pharmacological agents vessel vasodilation Piezo1-deficient mice, identifying quantitative differences between two groups. These results advance our understanding mechanodynamics offer potential implications developing targeted treatments disorders.

Язык: Английский

Процитировано

0
Evaluation of multispectral unmixing algorithm for HbO2 and HbR DOI
Ravi Prakash, Juliana Benavides, Kamran Avanaki

и другие.

Photons Plus Ultrasound: Imaging and Sensing 2021, Год журнала: 2024, Номер unknown, С. 153 - 153

Опубликована: Март 8, 2024

Multispectral photoacoustic tomography (sPAT) is a technique within imaging that aims to separate different types of chromophores using multiwavelength measurements. In this study, we conducted sPAT simulations for circular scanning detection setup the k-wave toolbox, focusing on two dominant absorbers in biological tissue: HbO2 and HbR. A phantom with three concentrations (100%, 70%, 30%) were simulated five pairs wavelengths (700nm,900nm; 756nm,900nm; 700nm,796nm; 756nm,796nm 900nm,796nm, respectively). Subsequently, supervised unmixing (Spectral Fitting) unsupervised algorithms, namely Principal Component Analysis (PCA), Independent (ICA), non-negative matrix factorization (NNMF), applied. The results then quantitatively compared unmixed evaluate their performance terms recovering concentration into simulation environment. study indicated based algorithm such as ICA was superior others them pair.

Язык: Английский

Процитировано

0
Photoacoustic computed tomography with improved quality DOI
Seyed Mohsen Ranjbaran, Mohsin Zafar, Loïc Saint‐Martin

и другие.

Photons Plus Ultrasound: Imaging and Sensing 2021, Год журнала: 2024, Номер unknown, С. 151 - 151

Опубликована: Март 11, 2024

This paper introduces an innovative approach to enhance the circular scanning-based photoacoustic tomography (CSPAT) system for imaging. The proposed method involves using a detection geometry with three carefully placed ultrasound transducers (USTs). By strategically selecting angles of USTs, field view (FOV) is expanded, and tangential resolution improved without requiring additional imaging time. new CS-PAT demonstrates practicality convenience, providing higher signal-to-noise ratio better structural similarity compared conventional system. overcomes limitations limited size USTs widens application potential in straightforward efficient manner.

Язык: Английский

Процитировано

0
A Deep Learning‐Based Approach to Characterize Skull Physical Properties: A Phantom Study DOI Creative Commons

Deepika Aggrawal,

Loïc Saint‐Martin, Rayyan Manwar

и другие.

Journal of Biophotonics, Год журнала: 2024, Номер 18(1)

Опубликована: Ноя. 14, 2024

Transcranial ultrasound imaging is a popular method to study cerebral functionality and diagnose brain injuries. However, the detected signal greatly distorted due aberration caused by skull bone. The mechanism mainly depends on thickness porosity, two important physical characteristics. Although bone porosity can be estimated from CT or MRI scans, there significant value in developing methods for obtaining information itself. Here, we extracted various features signals using skull-mimicking phantoms of range thicknesses with embedded porosity-mimicking acoustic mismatches analyzed them machine learning (ML) deep (DL) models. performance evaluation demonstrated that both ML- DL-trained models could predict characteristics variety reasonable accuracy. proposed approach expanded upon utilized development effective correction methods.

Язык: Английский

Процитировано

0
Laser scanning photoacoustic microscopy system for oxy/deoxy hemoglobin imaging DOI
Mohsin Zafar, Kamran Avanaki

Photons Plus Ultrasound: Imaging and Sensing 2021, Год журнала: 2024, Номер unknown, С. 149 - 149

Опубликована: Фев. 26, 2024

Язык: Английский

Процитировано

0
Photoacoustic imaging for detection of blood clot with different sizes in the brain DOI
Loïc Saint‐Martin, Seyed Mohsen Ranjbaran, Kamran Avanaki

и другие.

Photons Plus Ultrasound: Imaging and Sensing 2021, Год журнала: 2024, Номер unknown, С. 152 - 152

Опубликована: Фев. 26, 2024

During medical investigations of the head, presence skull bone constitutes a major challenge in generating accurate diagnostics. Photoacoustic imaging technology, with its functional capabilities, has demonstrated potential for brain at low cost and maintenance requirements. While photoacoustic signal generation deep tissue through been demonstrated, an effective method aberration correction transcranial not yet developed. In this study, we present based on enfolded learning algorithms that accurately compensates acoustic aberrations caused by head layers, allowing hemorrhage detection. Using realistic simulated framework, large quantity aberrated images is acquired, reconstructed, corrected.

Язык: Английский

Процитировано

0