Journal of Physics-Photonics最新文献

{"title":"FLIMExplorer: interactive GUI for object-based visualization and analysis of fluorescence lifetime images.","authors":"Blanche Ter Hofstede, Samantha Morganti, Daniela De Hoyos Canales, Anna Theodossiou, Amanda Galloway, Alex J Walsh","doi":"10.1088/2515-7647/ae7da3","DOIUrl":"10.1088/2515-7647/ae7da3","url":null,"abstract":"<p><p>Fluorescence lifetime imaging microscopy (FLIM) enables non-invasive measurement of cellular metabolism with single-cell and subcellular resolution, providing advantages over traditional population-level metabolic assays. However, current single-cell FLIM analysis workflows typically rely on multiple software tools for lifetime extraction, segmentation, and downstream analysis, often resulting in convoluted workflows and a disconnect between quantitative measurements and image context, limiting transparent quality control. Here, we present FLIMExplorer, an interactive, Python-based tool for downstream single-cell FLIM analysis and visualization. FLIMExplorer links quantitative FLIM endpoints and their underlying image objects, enabling users to explore key FLIM features (NAD(P)H and FAD: <i>τ</i> _m, <i>τ</i> ₁, <i>τ</i> ₂, and <i>α</i> ₁) at the single-cell level, visualize image objects corresponding to individual data points, and perform statistical comparisons across experimental groups within a single graphic user interface app. FLIMExplorer handles inputs of both (1) pixel-level FLIM outputs generated by upstream fitting software and (2) pre-processed, cell-average FLIM datasets. By integrating visualization, quality control, and statistical analysis at the single-cell level within a single platform, FLIMExplorer improves the integration of quantitative results with image context in downstream FLIM analysis.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 3","pages":"036001"},"PeriodicalIF":4.7,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13338917/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148406217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of light source parameters for photoacoustic imaging: trade-offs, technologies, and clinical considerations.","authors":"Kalloor Joseph Francis, David Veysset, Hwidon Lee, Brett E Bouma, Gijs van Soest","doi":"10.1088/2515-7647/ae889d","DOIUrl":"10.1088/2515-7647/ae889d","url":null,"abstract":"<p><p>The selection of light sources for photoacoustic imaging, a biomedical imaging technology, remains a critical yet under-informed topic. This review discusses the key trade-offs in light source parameters (e.g. wavelength, pulse energy, repetition frequency), safety, and practical considerations. We analyse these factors in the context of underlying imaging physics and the limits imposed by regulatory standards across various wavelength ranges. Attention is given to light source selection for photoacoustic tomography, optical and acoustic resolution microscopy, and endoscopy, which pose different requirements for pulse energies and repetition frequencies, to achieve real-time imaging at the desired depth. Current PA imaging light sources, including high-power lasers with optical parametric oscillators, fibre lasers, laser diodes, vertical-cavity surface-emitting lasers, and light-emitting diodes, are reviewed in terms of wavelength availability, energy, repetition frequency, beam quality, portability, and safety. Clinically viable systems require careful consideration of fibre coupling limitations, maximum permissible exposure at the tissue interface, imaging field of view, and signal-to-noise ratio. Further practical considerations include energy efficiency and thermal management in clinical settings. We also outline the present gaps in the available light source technologies, where the development of new sources may enable new PA imaging capabilities, both scientific and clinical. By offering an overview of these considerations, this review aims to guide researchers, industry, and clinicians in selecting optimal light sources and advancing the development of light sources that address current gaps in available technology.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 3","pages":"032001"},"PeriodicalIF":4.7,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13386801/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148550782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advances in fully integrated wearable near-infrared spectroscopy: hardware innovations and biomedical applications.","authors":"Shashikant Lahade, Nicholas Ross, Thomas D O'Sullivan","doi":"10.1088/2515-7647/ae6ae4","DOIUrl":"10.1088/2515-7647/ae6ae4","url":null,"abstract":"<p><p>The use of noninvasive near-infrared spectroscopy (NIRS) has grown significantly over the past few decades for use in the characterization of tissue optical properties and derived physiological parameters such as tissue oxygen saturation and hemoglobin composition to support human health and wellness. Wearable NIRS devices have been developed in recent years that enable real-time continuous monitoring. These devices have been enabled by advances in the dense integration of miniature integrated circuits, light sources and detectors, embedded processing, and wireless technologies. The most attractive aspect of wearable NIRS devices is that they enable real-time sensing both inside and outside of laboratory and clinical settings. This review paper focuses on recent hardware developments related to fully integrated wearable NIRS devices, including continuous wave, time domain, and frequency domain NIRS techniques, and their enabling technologies. We also review their application in biomedical fields such as neuroscience, musculoskeletal physiology, and others. We provide our perspective on the future technology research opportunities and direction of the field.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 2","pages":"022004"},"PeriodicalIF":4.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13216886/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148139083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial Second Harmonic Generation Image Feature Tuning with Generative Models and SeFa Semantic Analysis.","authors":"Melissa Champer, Vikas Singh, Paul Campagnola","doi":"10.1088/2515-7647/ae6c77","DOIUrl":"10.1088/2515-7647/ae6c77","url":null,"abstract":"<p><p>Collagen fibers within the extracellular matrix undergo morphological changes in the presence of many diseases including cancers and connective tissue disorders. Second Harmonic Generation (SHG) microscopy is ideal for visualizing this morphology by its intrinsic contrast and 3D imaging capabilities of fibrillar collagen. To build upon the success of deep learning-based methods analyzing microscopy datasets, in this study, we adapted the generative adversarial network model StyleGAN specifically for use with SHG data. Here we trained our model StyleGAN2-ADA-SHG on a dataset of 1,319 SHG images to extract further information content. When comparing evaluation metrics between the baseline dataset and the generator, we found that the model is well suited to generating novel images that appear perceptually similar to those from our small set of training data. Using Semantic Factorization (SeFa) on the generated images to examine the 10 highest scoring eigenvectors, we found two semantics with strong correlation to fiber morphological features that were quantified via analysis using CT-Fire, CurveAlign, and other fiber-based metrics. We integrated analysis tools into the SeFa GUI to support an extensible framework for future analyses and image editing. Additionally, we tested two image projection methods for editing SHG images in the GAN's latent space using the identified semantics. The encoder-based approach significantly outperformed the Learned Perceptual Image Patch Similarity (LPIPS) method. With further refinement, these tools can be used to create SHG images of collagen fibers with variable morphology based on disease types for additional analysis purposes.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 2","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13375112/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148473530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compact on-chip fluorescence microscope for dynamic imaging of cellular processes and biomimetic systems.","authors":"Somaiyeh Khoubafarin, Aakash Subramanian, William Daniel Gorgas, Cyrus Koogan, Indira Sigdel, Md Alamgir Kabir, Yuan Tang, Aniruddha Ray","doi":"10.1088/2515-7647/ae6ffe","DOIUrl":"10.1088/2515-7647/ae6ffe","url":null,"abstract":"<p><p>Real-time and High-throughput fluorescence imaging is essential for probing dynamic cellular behavior in biomimetic and tissue-on-chip systems. While fluorescence microscopy provides high sensitivity and subcellular resolution, the intrinsic heterogeneity of these engineered tissues requires imaging multiple regions to obtain representative biological information. Meeting this need typically demands mechanical scanning systems, which add both hardware and software complexity and substantially increase cost. Here, we developed a compact and low-cost on-chip fluorescence microscopy platform that integrates a two-dimensional microlens substrate directly onto a complementary metal-oxide-semiconductor sensor to achieve high resolution and signal-to-noise ratio (SNR). Excitation light is delivered laterally through a prism to induce total internal reflection, effectively rejecting background illumination and allowing only fluorescence emission to reach the detector. The system's optical geometry was optimized using analytical modeling and numerical simulations to maximize photon collection and SNR. Using this optimized system, we first demonstrated its capability at the cellular level by capturing drug-induced oxidative stress and rapid intracellular signaling dynamics in BT-20 breast cancer cells. Once we were successfully able to monitor these dynamic processes, we next applied the system to biomimetic models. In a microfluidic tumor-endothelial co-culture, we visualized the passage of small molecules, nanoparticles, and ions across the endothelial barrier under controlled flow conditions. Integration with microfluidic co-culture systems further demonstrated its ability to study complex interactions within tumor microenvironments. By combining simplicity, sensitivity, and compatibility with biomimetic platforms, this on-chip fluorescence microscope enables wide-field monitoring of cellular dynamics across large populations, allowing observation of cell-to-cell variability and supporting applications in drug screening, cellular signaling studies, and tissue-on-chip research.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 2","pages":"025047"},"PeriodicalIF":4.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13295382/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148346802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-layer self-calibrated algorithm for transabdominal fetal pulse oximetry: simulation and <i>in vivo</i> validation.","authors":"Jingyi Wu, Martin P Debreczeny, Nevan C Hanumara, Neil Ray, Baptiste Jayet, Stefan Andersson-Engels, Jana M Kainerstorfer","doi":"10.1088/2515-7647/ae1a27","DOIUrl":"10.1088/2515-7647/ae1a27","url":null,"abstract":"<p><p>Transabdominal fetal pulse oximetry offers a promising approach to non-invasively monitor fetal arterial oxygen saturation (SaO₂), potentially enhancing clinical decision-making and reducing unnecessary interventions during delivery. However, accurate estimation of fetal SaO₂ (denoted as SpO₂ when measured non-invasively) is complicated by the multi-layer maternal-fetal tissue structure, distinct maternal and fetal physiological signals, and inherently low fetal oxygen saturation levels. A multi-layer self-calibrated algorithm was developed by combining the multi-layer modified Beer-Lambert law with an analytical photon partial pathlength model. This approach distinguishes maternal and fetal tissue contributions, enabling more accurate fetal SpO₂ estimation. Validation was performed using Monte Carlo photon simulations of multi-layer tissue geometries, where synthetic optical signals representing fetal cardiac pulsations were generated under two fetal depths and randomly varied maternal and fetal oxygen saturations and optical properties. Further validation was performed using <i>in vivo</i> sheep data, where fetal SpO₂ values derived from transabdominal continuous-wave near-infrared spectroscopy measurements were compared against reference fetal SaO₂ from CO-oximetry. In simulations, the algorithm achieved a mean absolute error (MAE) below 5% and a Pearson correlation coefficient (<i>R</i>) of 0.98 between estimated fetal SpO₂ and ground truth fetal SaO₂ when using optimal input parameters. In the sheep experiment, agreement with reference measurements was maintained (MAE = 10.3%, <i>R</i> = 0.91). However, algorithm performance was highly sensitive to accurate optical properties and tissue layer thicknesses inputs, which may be challenging to obtain in clinical settings. These results demonstrate proof-of-concept feasibility for the multi-layer self-calibrated algorithm in both simulated and <i>in vivo</i> conditions. While further refinement, particularly in optical property estimation and fetal depths in human pregnancies, is necessary, this work provides a foundational framework for the future clinical translation of non-invasive fetal SpO₂ monitoring.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 1","pages":"015006"},"PeriodicalIF":8.4,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12603613/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145507487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generalized 3D quasi-phase-matching model of image contrast in second harmonic generation microscopy of fibrillar collagen architectures.","authors":"Emily M Shelton, Paul J Campagnola","doi":"10.1088/2515-7647/ae37b3","DOIUrl":"10.1088/2515-7647/ae37b3","url":null,"abstract":"<p><p>Second harmonic generation (SHG) microscopy is a powerful tool in assessing collagen structure, especially with respect to differentiating the respective architectures of normal and diseased tissues. An under-explored area is exploiting SHG to determine the sub-resolution aspects of the collagen fibril size, polarity, and packing (∼50-100 nm diameters). Due to the phase-matching and associated coherence of SHG, these structural aspects are encoded in the wavelength dependence of the spatial emission and relative conversion efficiency, denoted the creation attributes. As a means to extract this information, we present a generalized 3D computational/theoretical treatment based on quasi-phase-matching (QPM), which can predict the SHG emission pattern and relative conversion efficiency using collagen models based on 3D biomimetic fibril architectures. Specifically, we incorporate random rather than purely periodic structures and non-ideal phase-matching <math> <mrow><mrow><mo>(</mo> <mrow><mi>Δ</mi> <mi>k</mi> <mo>≠</mo> <mn>0</mn></mrow> <mo>)</mo></mrow> </mrow> </math> conditions. By exploration of parameter space, and comparison with imaging data, we can place bounds on the fibril architecture without the use of structural biology tools. The resulting predicted fibril sizes of real tissues are in good agreement with known values from electron microscopy. Moreover, by examining the role of heterogeneity, we have identified the contribution of small and large fibrils and clustering therein to the creation attributes, and the regimes where these dominate the spatial emission pattern. These simulations also resulted in good agreement with prior work on the wavelength dependence of SHG conversion efficiency, where the fibril size and packing are sufficient to reproduce experimental data without invoking a two-state model. This level of agreement provides validation of the model and also points to the need for this approach to treat the SHG responses due to the intrinsic complexity of many tissues.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 1","pages":"015045"},"PeriodicalIF":8.4,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12862596/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146114270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced accuracy of NIRS-vascular occlusion testing through incorporation of conduit artery diameter.","authors":"Soongho Park, Julie Mathew, Eric Leifer, Sharon Osgood, Claudia Gomez, Hans Ackerman, Yogendra Kanthi","doi":"10.1088/2515-7647/ae4862","DOIUrl":"10.1088/2515-7647/ae4862","url":null,"abstract":"<p><p>Near-infrared spectroscopy with vascular occlusion testing (NIRS-VOT) offers a non-invasive approach for real-time assessment of tissue oxygenation and vascular function. However, its clinical application remains limited, in part due to substantial inter-individual variability in anatomical and physiological characteristics. To identify potential sources of variability, we explored whether incorporating conduit artery size-specifically baseline brachial artery diameter (BrAD)-into the NIRS-VOT data analysis could enhance physiological interpretation and reduce measurement error. We analyzed NIRS-VOT responses from 16 healthy participants recruited to the NIH Clinical Center (NCT06552767 and NCT03538639), incorporating individual BrAD measurements as a covariate. Strong to moderate Spearman's rank-order correlations were observed between BrAD and dynamic perfusion parameters, including the desaturation rate ( <math><mrow><mi>ρ</mi></mrow> </math> = 0.77, <i>p</i> = 0.0005) and resaturation rate ( <math><mrow><mi>ρ</mi></mrow> </math> = 0.79, <i>p</i> = 0.0003). These findings suggest that larger brachial arteries are associated with greater oxygen extraction during occlusion and faster reoxygenation during reperfusion. Across parameters, BrAD explained a substantial proportion of the variance in NIRS-VOT outcomes. When BrAD was included as a covariate, the unexplained variability in the desaturation and resaturation rates was reduced to 28% and 34% of the total variance, respectively, indicating that accounting for conduit artery size substantially decreases residual variability and enhances the interpretability of these dynamic responses. Visual comparison also indicated that incorporating BrAD helped clarify response patterns and reclassify outliers. By reducing inter-individual variability and explaining a greater share of the physiological response, the BrAD-informed analysis enhances the interpretability and consistency of NIRS-VOT measurements. Integrating vascular anatomy into NIRS-VOT analysis may improve the detection of subtle vascular dysfunction and strengthen its diagnostic utility. Future research involving larger and more diverse cohorts, and additional vascular territories are needed to validate and expand these findings.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"8 1","pages":"015063"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12946859/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147327639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolating subsurface fluorescence in macroscopic lifetime imaging via high-spatial-frequency structured illumination.","authors":"Nanxue Yuan, Saif Ragab, Navid Nizam, Vikas Pandey, Amit Verma, Tynan Young, John Williams, Margarida Barroso, Xavier Intes","doi":"10.1088/2515-7647/ae0aa1","DOIUrl":"10.1088/2515-7647/ae0aa1","url":null,"abstract":"<p><p>Macroscopic fluorescence lifetime imaging (MFLI) has emerged as a robust, non-invasive imaging technique offering quantitative insights into physiological and molecular processes within live tissues, independent of fluorophore concentration, excitation intensity, or signal attenuation. However, a key limitation is the inability to accurately determine the depth at which fluorescence signals originate, potentially compromising biological interpretation due to ambiguous localization. In this study, we introduce high spatial frequency-fluorescence lifetime imaging (HSF-FLI), an innovative optical correction methodology designed to effectively eliminate surface signal bias, such as those arising from skin in preclinical imaging, without requiring chemical clearing agents. We develop a modulation transfer function linking spatial frequency with signal penetration depth through comprehensive Monte Carlo eXtreme simulations. Utilizing structured, three-phase sinusoidal illumination, fluorescence signals were accurately decomposed into distinct surface and subsurface components. Experimental validation was performed using agar-based capillary phantoms and a time-gated intensified charged coupled device coupled with a digital micromirror device imaging system. Further demonstrating its practical utility, we successfully applied HSF-FLI to preclinical drug delivery assessments employing Förster resonance energy transfer MFLI. The method was rigorously validated <i>in vivo</i> using mouse tumor xenograft models and cross-validated through <i>ex vivo</i> analyses. Overall, by integrating structure illumination techniques with physics-based depth modeling, HSF-FLI achieves precise depth-selective FLI. This advancement significantly enhances the accuracy, biological interpretation, and applicability of FLI, positioning HSF-FLI as a valuable tool for translational research.</p>","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"7 4","pages":"045028"},"PeriodicalIF":4.7,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12498145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145245441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-parametric photoacoustic elastomicroscopy: quantitative elasticity mapping and microstructural analysis for early-stage hepatic fibrosis detection","authors":"Weiran Pang, Qi Zhou, Yang Qiu, Haofan Huang, Jiali Chen, Tianting Zhong, Yingying Zhou, Liming Nie, Puxiang Lai","doi":"10.1088/2515-7647/ae0541","DOIUrl":"https://doi.org/10.1088/2515-7647/ae0541","url":null,"abstract":"Abstract Early detection of hepatic fibrosis remains a critical unmet need due to the limited sensitivity of conventional elastography in capturing microstructural and biomechanical changes. In this study, we developed photoacoustic elastomicroscopy (PAEM), a multi-parametric imaging platform that synergizes high-resolution photoacoustic microscopy with time-of-flight (ToF)-based elastography to quantitatively map tissue stiffness and visualize fibrotic microarchitecture. Validated using PDMS phantoms and a drug-induced murine fibrosis model, PAEM can detect early-stage fibrosis through microstructural biomarkers—pseudo-lobule formation and crevice-area expansion, with a relatively high area under the curve (AUC) &gt; 0.91. However, architectural ambiguity in advanced fibrotic stages gradually reduces PAEM’s diagnostic accuracy, necessitating complementary reliance on ToF-based measurements for auxiliary staging. In our results, ToF-based elasticity biomarkers revealed progressive stiffness increases with a significant velocity increase of 3.7% in 1-week fibrosis. Furthermore, experimental PAEM outperformed shear wave elastography (SWE) in early-stage sensitivity by identifying significant stiffness changes, quantitatively 7-fold greater velocity differential sensitivity than SWE (5.39% vs. 0.77% change), between healthy and 3-week fibrotic liver tissue. All-stage fibrosis exhibited a considerable stiffness rise (AUC &gt; 0.95), correlating strongly with histopathological severity and serum examination. By integrating structural and mechanical biomarkers, PAEM offers a translational tool for early diagnosis, longitudinal monitoring, and staging of hepatic fibrosis, which can potentially be extended for wider applications in tumor margin delineation and other fibrotic pathologies in soft tissue.","PeriodicalId":44008,"journal":{"name":"Journal of Physics-Photonics","volume":"7 4","pages":"045038-045038"},"PeriodicalIF":0.0,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147331003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}