A deep convolutional neural network for diffuse correlation tomography

Applied Physics Letters, Journal Year: 2025, Volume and Issue: 126(8)

Published: Feb. 1, 2025

Near-infrared diffuse correlation tomography (DCT) is an emerging technology for tomographic imaging of blood flow index (BFI) in biological tissues through quantifying the light electric field temporal autocorrelation function. With conventional approaches, proper reconstruction BFI images a challenging task from limited DCT signals due to severe imbalance between optical measurements and voxels be reconstructed. In this study, we proposed complete deep learning solution DCT, including dataset containing massive prior information network training, long short-term memory neural signal denoising, as well convolutional mapping into images. The was comprehensively validated both computer simulations phantom experiments, demonstrating its strong superiority over approach precise robustness reconstructions target anomalies, with much better performance reducing errors (i.e., mean absolute error reduced by 26.1 times) preserving fine structure similarity measure increased 12.8 times). establishment strategy enables future exploration microvasculature mechanism on pathological even signals.

Language: Английский

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AI-assisted diffuse correlation tomography for identifying breast cancer

Journal of Biomedical Optics, Journal Year: 2025, Volume and Issue: 30(05)

Published: May 16, 2025

Diffuse correlation tomography (DCT) is an emerging technique for the noninvasive measurement of breast microvascular blood flow, whereas its capability to categorize benign and malignant lesions has not been extensively validated thus far, due difficulties in instrumentation, image reconstruction algorithms, appropriate approaches imaging analyses. This artificial intelligence (AI)-assisted DCT instrumentation was constructed based on a unique source-detector array algorithm. The images breasts were obtained from 61 females, AI models utilized classify lesions. During this process, flow either extracted as feature parameters or global inputs models. As validations longitudinal monitoring healthy subjects demonstrated stability measurements. For patients with diseases, comprehensive analyses yield AI-assisted classification excellent performance distinguishing between lesions, at accuracy 97%. reflects functional abnormalities that are associated cancellous-induced high metabolic demands, demonstrating great potential early diagnosis timely therapeutic assessment cancer, e.g., prior tumor formation proliferation networks.

Language: Английский

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Transcranial Optical Monitoring of Cerebral Hemodynamics in Acute Stroke Patients during Mechanical Thrombectomy

Journal of Stroke and Cerebrovascular Diseases, Journal Year: 2019, Volume and Issue: 28(6), P. 1483 - 1494

Published: April 8, 2019

Language: Английский

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Diffuse correlation spectroscopy and frequency-domain near-infrared spectroscopy for measuring microvascular blood flow in dynamically exercising human muscles

Journal of Applied Physiology, Journal Year: 2019, Volume and Issue: 127(5), P. 1328 - 1337

Published: Sept. 12, 2019

In the last 20 yr, near-infrared diffuse correlation spectroscopy (DCS) has been developed for providing a noninvasive estimate of microvascular blood flow (BF) as BF index (BF i ) in human skin, muscle, breast, brain, and other tissue types. this study, we proposed new motion correction algorithm DCS-derived able to remove artifacts during cycling exercise. We tested on DCS data collected exercise demonstrated that can be used quantify muscle dynamic high-intensity addition, measured regional oxygen metabolic rate (MRO 2i by combining frequency-domain multidistance (FDNIRS) oximetry with measures. Recreationally active subjects ( n = 12; 31 ± 8 183 4 cm, 79 10 kg) pedaled at 80–100 revolutions/min until volitional fatigue work increase 30 W every min. Exercise intensity was normalized each subject power peak (W ). Both rectus femoris MRO increased from 15% up 75% then plateaued end During recovery power, remained almost constant, whereas started decrease. The /MRO plateau associated rising lactate concentration, indicating progressive involvement anaerobic metabolism. These findings further highlight utility FDNIRS effective, reproducible, techniques assess real time such cycling. NEW & NOTEWORTHY To best our knowledge, study is first demonstrate combination monitor quadriceps metabolism high temporal resolution optically parameters confirm expected relationship between flow, oxidative metabolism, production

Language: Английский

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Nanoparticles for Stem Cell Tracking and the Potential Treatment of Cardiovascular Diseases

Frontiers in Cell and Developmental Biology, Journal Year: 2021, Volume and Issue: 9

Published: July 2, 2021

Stem cell-based therapies have been shown potential in regenerative medicine. In these cells, mesenchymal stem cells (MSCs) the ability of self-renewal and being differentiated into different types such as cardiovascular cells. Moreover, MSCs low immunogenicity immunomodulatory properties, can protect myocardium, which are ideal qualities for repair. Transplanting has demonstrated improved outcomes treating diseases preclinical trials. However, there still some challenges, their rate migration to ischemic tissue retention, survival after transplantation. To solve problems, an method should be developed precisely quantitatively monitor viability transplanted vivo providing guidance clinical translation. Cell imaging is method, but requires a suitable contrast agent label track This article reviews uses nanoparticles agents tracking challenges use treatment diseases.

Language: Английский

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Deep-learning-based separation of shallow and deep layer blood flow rates in diffuse correlation spectroscopy

Biomedical Optics Express, Journal Year: 2023, Volume and Issue: 14(10), P. 5358 - 5358

Published: Sept. 13, 2023

Diffuse correlation spectroscopy faces challenges concerning the contamination of cutaneous and deep tissue blood flow. We propose a long short-term memory network to directly quantify flow rates shallow deep-layer tissues. By exploiting different contributions auto-correlation functions, we accurately predict (RMSE = 0.047 0.034 ml/min/100 g simulated tissue, R2 0.99 0.99, respectively) in two-layer phantom experiment. This approach is useful evaluating responses active muscles, where both deep-muscle increase with exercise.

Language: Английский

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Studies into the determinants of skeletal muscle oxygen consumption: novel insight from near‐infrared diffuse correlation spectroscopy

The Journal of Physiology, Journal Year: 2019, Volume and Issue: 597(11), P. 2887 - 2901

Published: April 15, 2019

Diffuse correlation spectroscopy (DCS) is emerging as a powerful tool to assess skeletal muscle perfusion. Near-infrared (NIRS) an established technique for characterizing the transport and utilization of oxygen through microcirculation. Here we compared combined NIRS-DCS system with conventional measures delivery during handgrip exercise. The data show good concurrent validity between convective DCS-derived blood flow index, well extraction at conduit microvascular level. We then manipulated forearm arterial perfusion pressure by adjusting position exercising arm relative heart. that can be uncoupled from delivery, tissue saturation seemingly compensates maintain consumption. Taken together, these support novel role in understanding determinants consumption level.Diffuse Combining DCS near-infrared introduces exciting possibilities consumption; however, no investigation has directly limb. To address this knowledge gap, nine healthy males performed rhythmic exercise simultaneous measurements NIRS-DCS, Doppler venous content. two approaches showed validity, directionally similar responses between: (a) Doppler-derived index (BFI), (b) NIRS-derived saturation. explore utility across physiological spectrum, altering above or below level As expected, increased both positions, but markedly different magnitudes (below: +424.3 ± 41.4 ml/min, above: +306 12.0 P = 0.002). In contrast, BFI extent exercise, regardless (P 0.65). Importantly, time reach steady state was slower heart, supporting experimental design. Notably, observed faster desaturation onset resulting profiles throughout non-invasively

Language: Английский

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Comparison of cerebral metabolic rate of oxygen, blood flow, and bispectral index under general anesthesia

Neurophotonics, Journal Year: 2023, Volume and Issue: 10(01)

Published: March 6, 2023

SignificanceThe optical measurement of cerebral oxygen metabolism was evaluated.AimCompare optically derived signals to the electroencephalographic bispectral index (BIS) sensors monitor propofol-induced anesthesia during surgery.ApproachRelative metabolic rate (rCMRO2) and blood flow (rCBF) were measured by time-resolved diffuse correlation spectroscopies. Changes tested against relative BIS (rBIS) ones. The synchronism in changes also assessed R-Pearson correlation.ResultsIn 23 measurements, showed significant agreement with rBIS: propofol induction, rBIS decreased 67% [interquartile ranges (IQR) 62% 71%], rCMRO2 33% (IQR 18% 46%), rCBF 28% 10% 37%). During recovery, a increase observed for (48%, IQR 38% 55%), (29%, 17% 39%), (30%, 44%). significance direction subject-by-subject tested: coupling between rBIS, rCMRO2, witnessed majority cases (14/18 12/18 19/21 13/18 initial final part, respectively). These correlated time (R > 0.69 R = 1, p-values < 0.05).ConclusionsOptics can reliably such conditions.

Language: Английский

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High Responsivity of InP/InAsP Nanowire Array Broadband Photodetectors Enhanced by Optical Gating

Nano Letters, Journal Year: 2019, Volume and Issue: 19(12), P. 8424 - 8430

Published: Nov. 13, 2019

High-performance photodetectors operating in the near-infrared (0.75-1.4 μm) and short-wave infrared (1.4-3.0 portion of electromagnetic spectrum are key components many optical systems. Here, we report on a combined experimental theoretical study square millimeter array comprising 3 million n+-i-n+ InP nanowires grown by MOVPE from periodically ordered Au seed particles. The nominal i-segment, 20 InAs0.40P0.60 quantum discs, was use an optimized Zn doping to compensate nonintentional n-doping. exhibit bias- power-dependent responsivities reaching record-high values 250 A/W at 980 nm/20 nW 990 532 nm/60 nW, both 3.5 V bias. Moreover, due embedded photoresponse covers broad spectral range about 0.70 2.5 eV, effect outperforming conventional single InGaAs detectors dual Si/Ge detectors. high responsivity, related gain, results novel proposed photogating mechanism, induced complex charge carrier dynamics involving excitation recombination discs interface traps, which reduces electron transport barrier between highly doped n+ contact i-segment. obtained perfect agreement with model represent significant step forward toward understanding gain nanoscale realization commercially viable broadband photon ultrahigh gain.

Language: Английский

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Portable Near-Infrared Technologies and Devices for Noninvasive Assessment of Tissue Hemodynamics

Journal of Healthcare Engineering, Journal Year: 2019, Volume and Issue: 2019, P. 1 - 11

Published: Feb. 12, 2019

Tissue hemodynamics, including the blood flow, oxygenation, and oxygen metabolism, are closely associated with many diseases. As one of portable optical technologies to explore human physiology assist in healthcare, near-infrared diffuse spectroscopy (NIRS) for tissue oxygenation measurement has been developed four decades. In recent years, a dynamic NIRS technology, namely, correlation (DCS), emerging as tool flow measurement. this article, we briefly describe basic principle algorithms static (i.e., DCS). Then, elaborate on instrumentation, either commercially available or custom-made, well their applications physiological studies clinic. The extension NIRS/DCS from imaging was depicted, followed by introductions advanced that were recently proposed. future prospective feasibilities routine utilization hospital is finally discussed.

Language: Английский

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