Biomedical optics express最新文献

{"title":"Three-dimensional monitoring of RBC sedimentation in external magnetic fields.","authors":"Kowsar Gholampour, Ali-Reza Moradi","doi":"10.1364/BOE.545723","DOIUrl":"10.1364/BOE.545723","url":null,"abstract":"<p><p>The external magnetic fields resulting from electronic devices around humans have become more prevalent nowadays, and studying their influence on living matter is a required task. Here, we experimentally model the movement of RBCs in veins under an external magnetic field; we monitor the sedimentation of multiple RBCs at different distances from a surrounding wall. The monitoring is performed in 3D by incorporation of digital holographic microscopy (DHM). DHM not only provides a 3D quantitative phase image of an RBC but also, through its numerical refocusing feature, 3D trajectories of several cells in the field of view can be obtained. Our results show that the magnetic field facilitates the sedimentation of cells, and the effect is higher in proximity to the walls. This influence is attributed to the presence of magnetic field-sensitive materials included in RBCs.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"736-747"},"PeriodicalIF":2.9,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828455/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enabling real-time reconstruction for large field-of-view single-molecule localization microscopy using discrete field-dependent point-spread function.","authors":"Jun Lu, Lei Xu, Shuyao Liao, Wei Wang, Biqin Dong","doi":"10.1364/BOE.545534","DOIUrl":"10.1364/BOE.545534","url":null,"abstract":"<p><p>Single-molecule localization microscopy (SMLM) is a powerful super-resolution imaging technique that offers resolution far beyond the optical diffraction limit. The commonly used high numerical-aperture (NA) objective lenses in SMLM can only provide a nearly ideal point-spread function (PSF) at the center of the field-of-view (FOV), whereas the off-axis PSF is often distorted due to optical aberrations. Since precision and accuracy of three-dimensional (3D) spatial localization of single molecules heavily depend on the system's PSF, the FOV of 3D SMLM is often restricted to about 50 µm × 50 µm limiting its applications in visualizing intra-/intercellular interactions and high-throughput single-molecule analysis. Here we present a systematic study to show the influence of optical aberrations on large FOV 3D SMLM using unmodified, astigmatic, and double-helix PSFs. Our results show that optical aberrations introduce significant localization errors during image reconstruction and thereby produce unreliable imaging results at the corner of the FOV. To maximize SMLM's FOV, we proposed and verified the potential of using discrete field-dependent PSFs to retain precise and accurate single-molecule localization and compare their reconstruction results using simulated resolution test patterns and biological structures. Moreover, GPU acceleration empowers a discrete PSF calibration model with high localization speed, which can provide real-time SMLM image reconstruction. We envision these results will further guide the development of strategies that can provide real-time and reliable image reconstruction in large FOV 3D SMLM.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"718-735"},"PeriodicalIF":2.9,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of monocular defocus curves in pseudophakia with different pupil sizes.","authors":"Antonio J Del Águila-Carrasco, Aixa Alarcon, Henk Weeber, Linda Tsai, Srividhya Vilupuru, Carmen Canovas, Patricia Piers","doi":"10.1364/BOE.540583","DOIUrl":"10.1364/BOE.540583","url":null,"abstract":"<p><p>Existing models for predicting clinical visual acuity (VA) following lens replacement surgery use controlled experimental conditions where pupil size is typically fixed. However, pupil size may influence visual performance depending on the design of the intraocular lens (IOL) implanted. This study compares optical bench testing metrics to clinical VA in pseudophakic patients with different pupil sizes and IOL models. The area under the modulation transfer function (MTFa) and the weighted optical transfer function (wOTF) were obtained at vergences ranging from -3 D to 0.5 D, and different pupil sizes: 2, 3, and 4.5 mm. The simulated VA values obtained for both metrics were well correlated with clinical data (R² ≥ 0.85) and had low root mean square errors (RMSe) for the entire defocus range, suggesting their suitability for predicting VA defocus curves in pseudophakic eyes with varying pupil size.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"709-717"},"PeriodicalIF":2.9,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828456/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenging the skin pigmentation bias in tissue oximetry via time-domain near-infrared spectroscopy.","authors":"Michele Lacerenza, Caterina Amendola, Ilaria Bargigia, Alessandro Bossi, Mauro Buttafava, Valeria Calcaterra, Davide Contini, Vamshi Damagatla, Fabio Negretti, Virginia Rossi, Lorenzo Spinelli, Sara Zanelli, Gianvincenzo Zuccotti, Alessandro Torricelli","doi":"10.1364/BOE.541239","DOIUrl":"10.1364/BOE.541239","url":null,"abstract":"<p><p>Recently, skin pigmentation has been shown to affect the performance of pulse oximeters and other light-based techniques like photo-acoustic imaging, tissue oximetry, and continuous wave near-infrared spectroscopy. Evaluating the robustness to changes in skin pigmentation is therefore essential for the proper use of optical technologies in the clinical scenario. We conducted systematic time-domain near-infrared spectroscopy measurements on calibrated tissue phantoms and in vivo on volunteers during static and dynamic (i.e., arterial occlusion) measurements. To simulate varying melanosome volume fractions in the skin, we inserted, between the target sample and the measurement probe, thin tissue phantoms made of silicone and nigrosine (skin phantoms). Additionally, we conducted an extensive measurement campaign on a large cohort of pediatric subjects, covering the full spectrum of skin pigmentation. Our findings consistently demonstrate that skin pigmentation has a negligible effect on time-domain near-infrared spectroscopy results, underscoring the reliability and potential of this emerging technology in diverse clinical settings.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"690-708"},"PeriodicalIF":2.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828448/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polarimetric imaging of peripheral nerves: an intraoperative aid.","authors":"Haolin Liao, David J Mitten, Wayne H Knox","doi":"10.1364/BOE.545146","DOIUrl":"10.1364/BOE.545146","url":null,"abstract":"<p><p>In this work, we present a real-time method to aid intraoperative peripheral nerve identification. Using LEDs as the light sources, the device contains a driving motor that rotates a pair of orthogonally oriented linear polarizers. By performing lock-in processing to frames taken under the rotating crossed polarization imaging (RXPI) system, the AC components of the periodic intensity signal of chicken tissues are acquired and compared. With an area under the curve (AUC) of 93%, the chicken sciatic nerve is distinct for automatic identification. In both chicken thigh and cadaver arm models, the contrasts of nerve tissues are successfully enhanced in the lock-in processed output image. Real-time automatic nerve masking is successfully demonstrated in the chicken model using a portable prototype weighing 525 g. In conclusion, the RXPI system with lock-in processing methods can potentially serve as an intraoperative nerve identification aid.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"679-689"},"PeriodicalIF":2.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828436/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compact and aberration effects-shielded objective intraocular scatter measurement system.","authors":"Junlei Zhao, Zitao Zhang, Yanrong Yang, Haobo Zhang, Hao Chen, Shengqian Wang, Yun Dai","doi":"10.1364/BOE.545245","DOIUrl":"10.1364/BOE.545245","url":null,"abstract":"<p><p>The measurement of the double-pass (DP) point spread function (PSF) provides an objective, non-invasive method for estimating intraocular scatter in the human eye. In this paper, we propose a compact double-pass objective intraocular scatter measurement system that eliminates the influence of aberrations. The system includes a far-field DP PSF detection channel and a Shack-Hartmann wavefront aberration detection channel, which are used to obtain the far-field DP PSF image and 7 orders Zernike aberration coefficients, respectively. The far-field DP PSF image is used to calculate the initial objective scatter index of the human eye. The aberration coefficients are used to reconstruct the DP PSF image caused by aberrations and calculate the influence coefficient of aberrations on intraocular scatter. By subtracting this influence coefficient from the initial objective scatter index (OSI0), the effect of aberrations on scatter measurement can be eliminated, resulting in an accurate objective scatter coefficient. Experimental verification showed that when the exit pupil aperture of this system was set to 4 mm and 6 mm, the measurement accuracy increased by at least 11.9% and 28.9%, respectively, compared to before eliminating the influence of aberrations. While improving the measurement accuracy, the system also keeps the device size and manufacturing costs at a low level, making it more suitable for clinical applications.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"669-678"},"PeriodicalIF":2.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828433/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demonstration of femtosecond laser induced refractive index change in silk-fibroin hydrogels.","authors":"Quazi Rushnan Islam, Rocio Gutierrez-Contreras, Susana Marcos, Wayne H Knox","doi":"10.1364/BOE.546884","DOIUrl":"10.1364/BOE.546884","url":null,"abstract":"<p><p>We present induced refractive index changes in biocompatible silk fibroin hydrogels using two different femtosecond laser systems: one using 400 nm at 80 MHz and the other employing 517 nm at 8.3 MHz. Both modalities produced significant index changes, demonstrating the potential to create custom refractive correctors. Additionally, the biocompatibility and environmentally friendly properties of silk-fibroin make it an ideal platform for developing new types of intraocular implants that incorporate tunable refractive corrections.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"657-668"},"PeriodicalIF":2.9,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828447/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of tactile feedback in post-stroke hand rehabilitation on functional connectivity and cortical activation: an fNIRS study.","authors":"Lingling Chen, Fanyao Meng, Congcong Huo, Guangjian Shao, Guoxin Pan, Xuemin Zhang, Simin Zhang, Zengyong Li","doi":"10.1364/BOE.541820","DOIUrl":"10.1364/BOE.541820","url":null,"abstract":"<p><p>Stroke-induced hand motor impairments have a significant impact on the daily lives of patients. Motor rehabilitation with tactile feedback (TF) shows promise as an effective rehabilitation intervention; however, its neural mechanisms are still not fully understood. The main objective of this study was to examine the effect of tactile feedback on brain functional responses during a single hand movement session in post-stroke patients, using functional near-infrared spectroscopy (fNIRS). The changes in oxy- and deoxy-hemoglobin concentrations were recorded from the bilateral prefrontal, motor, and occipital areas in 13 post-stroke patients in the subacute recovery phase and 15 healthy controls during a hand-grasping task with TF and no-TF. The cortical activation responses, functional connectivity, and brain functional network properties were calculated to explore the specific cortical response in post-stroke patients and healthy controls during the two grasping tasks. The results showed that post-stroke patients exhibited increased hemodynamic responses in the motor cortex during grasping tasks with TF. However, brain activation in the prefrontal cortex, left sensorimotor cortex, and right premotor area was significantly lower in post-stroke patients compared to healthy controls (p < 0.05). Additionally, post-stroke patients exhibited poorer overall brain network function, with significant reductions in both clustering coefficient (p = 0.0016), reflecting local information transfer efficiency, and transitivity (p = 0.0053), representing global network integration. A significant positive correlation was observed between the clustering coefficient and grip strength metrics (r = 0.592, p = 0.033), as well as between transitivity and grip strength (r = 0.590, p = 0.034) in post-stroke patients, indicating that greater impairments were associated with reduced overall brain functional network transmission efficiency. These findings indicated that TF can modulate brain activity in areas associated with motor learning and sensorimotor integration, providing evidence for its potential as a valuable tool in stroke rehabilitation.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"643-656"},"PeriodicalIF":2.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828458/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative numerical analysis of astigmatism tolerance in bifocal, extended depth-of-focus, and trifocal intraocular lenses.","authors":"Jongin You, Mooseok Jang","doi":"10.1364/BOE.537654","DOIUrl":"10.1364/BOE.537654","url":null,"abstract":"<p><p>Here, we quantitatively assess the effect of astigmatism on visual functions in eyes with three different commercial multifocal intraocular lenses (IOLs) using a customized finite eye model. Our proposed model implements a full wave analysis of the whole eye structure with diffractive multifocal IOLs under polychromatic conditions. The proposed eye model evaluates the energy efficiency of each focus at varying degrees of corneal astigmatism with the light-in-the-bucket metrics for bifocal (Restor), extended depth-of-focus (Symfony), and trifocal IOLs (POD-F). Better tolerance under astigmatic conditions was observed in the order of Symfony, Restor, and POD-F, highlighting the need to consider multifocal toric IOLs with corneal astigmatism greater than +1.5 D, + 1.0 D, and +1.0 D for Symfony, Restor, and POD-F, respectively. Furthermore, we revealed the way that the optical properties of multifocal IOLs, including the optical power of the diffractive part, the effect of high-order harmonics, and chromatic aberration, interplay to determine the tolerance for corneal aberration. The numerical analysis closely agrees with previous clinical studies on determining the indication for multifocal toric IOLs, suggesting the clinical usability of the presented method in predicting the postoperative visual function of patients on a customized basis.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"628-642"},"PeriodicalIF":2.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828457/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recording dynamic facial micro-expressions with a multi-focus camera array.","authors":"Lucas Kreiss, Weiheng Tang, Ramana Balla, Xi Yang, Amey Chaware, Kanghyun Kim, Clare B Cook, Aurelien Begue, Clay Dugo, Mark Harfouche, Kevin C Zhou, Roarke Horstmeyer","doi":"10.1364/BOE.547944","DOIUrl":"10.1364/BOE.547944","url":null,"abstract":"<p><p>We present a multi-camera array for capturing dynamic high-resolution videos of the human face. Compared to traditional single-camera configurations, our array of 54 individual cameras allows stitching of high-resolution composite video frames (709 megapixels total). In our novel multi-focus strategy, each camera in the array focuses on a unique object plane to resolve non-planar surfaces at a higher resolution than a standard single-lens camera design. By overcoming the standard resolution and depth-of-field (DOF) tradeoffs, we use our array design to capture video of macroscopically curved surfaces such as the human face at a lateral resolution of 26.14 ± 5.8 µm across a composite DOF of ∼43 mm that covers the entire face (85 cm²+ FOV). Compared to a single-focus configuration, this is almost a 10-fold increase in effective DOF. We demonstrate how our multi-focus camera array can capture dynamic facial expressions at microscopic resolution with relevance in several biomedical applications.</p>","PeriodicalId":8969,"journal":{"name":"Biomedical optics express","volume":"16 2","pages":"617-627"},"PeriodicalIF":2.9,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828449/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}