Biocybernetics and Biomedical Engineering最新文献

{"title":"Interferometric speckle contrast optical spectroscopy (iSCOS) in continuous-wave parallel interferometric near-infrared spectroscopy (CW-πNIRS)","authors":"Klaudia Nowacka-Pieszak ,&nbsp;Saeed Samaei ,&nbsp;Dawid Borycki","doi":"10.1016/j.bbe.2025.11.001","DOIUrl":"10.1016/j.bbe.2025.11.001","url":null,"abstract":"<div><div>Optical methods enable continuous, noninvasive cerebral blood flow (CBF) monitoring. Diffuse correlation spectroscopy (DCS) estimates CBF through temporal correlation analysis of scattered light but is limited by low detection throughput. Parallelizing DCS enhances performance but requires costly ultra-fast (∼1 MHz) detectors, complicating continuous measurements. An alternative approach analyzes spatial correlations using speckle contrast, inversely proportional to blood flow, captured with slower two-dimensional sensors. In this study, we present continuous-wave parallel interferometric near-infrared spectroscopy (CW-πNIRS), employing interferometry combined with a high-speed 2D camera, as a novel method uniquely suited for spatial correlation measurements. By leveraging interferometric detection, our approach provides a synthetic multi-exposure capability for direct quantitative comparisons between spatial (speckle contrast) and temporal (autocorrelation) methods for CBF monitoring. Numerical simulations, incorporating interferometric reference fields, and tissue-mimicking phantom validations demonstrated robust, and stable speckle contrast estimates. Finally, <em>in vivo</em> experiments confirmed the method’s potential for effective human cerebral blood flow monitoring, highlighting practical advantages and providing a clear pathway towards clinical implementation.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 669-684"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145465358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced computer-aided system for breast lesion classification and grading using novel radio frequency time series approach","authors":"Elaheh Norouzi Ghehi ,&nbsp;Ali Fallah ,&nbsp;Saeid Rashidi ,&nbsp;Maryam Mehdizadeh Dastjerdi","doi":"10.1016/j.bbe.2025.10.003","DOIUrl":"10.1016/j.bbe.2025.10.003","url":null,"abstract":"<div><h3>Objective</h3><div>Breast cancer is the most common malignancy among women and leading cause of mortality. Accurate, non-invasive differentiation of benign and malignant lesions is a clinical priority to reduce unnecessary biopsies and enable timely treatment. Elastography and RF time series (RF TS) processing are effective ultrasound-based techniques for tissue characterization. To improve their accuracy, we introduced an innovative approach called RFTSDP (RF Time Series Dynamic Processing). In RFTSDP, data are recorded during mechanical stimulation, revealing tissue properties in RF echoes. Extracting relevant features enhances computer-aided methods and improves tissue classification and grading.</div></div><div><h3>Materials and methods</h3><div>An implement was developed to induce vibrations at different frequencies. Data were collected from ex-vivo tissues embedded in normal mimicking phantoms. Raw focused, raw, and beamformed ultrafast data were recorded under no stimulation, constant force, and various vibrational stimulations using the Supersonic Imaging Aixplorer ultrasound system. Features were extracted from each RF TS across the time, time–frequency, spectral, and non-linear domains. Multiple classifiers were evaluated, among which support vector machines with different kernels achieved the best results.</div></div><div><h3>Results</h3><div>Beyond the classification of cancerous versus non-cancerous tissue, we also classified different cancerous lesion types and graded invasive ductal carcinoma. The best results were achieved with beamformed ultrafast data under 65 Hz vibrational stimulation. The mean classification accuracies for 2-, 3-, and 5-class were 99.78 %, 99.06 % and 99.32 %, respectively.</div></div><div><h3>Conclusions</h3><div>The outcomes affirm that applying vibration, particularly at an optimal frequency, enhances breast tissue classification. The proposed method demonstrated efficacy not only in distinguishing between cancerous and non-cancerous lesions but also in grading cancerous tissues.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 655-668"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating core body temperature from heart rate using a residual-compensated adaptive Kalman filter","authors":"Yuanzhe Zhao ,&nbsp;Jeroen H.M. Bergmann","doi":"10.1016/j.bbe.2025.10.001","DOIUrl":"10.1016/j.bbe.2025.10.001","url":null,"abstract":"<div><div>Accurate, real-time estimation of core body temperature is critical for preventing heat-related illness. While existing Kalman filter-based methods offer interpretable, single-input (heart rate) solutions, they are limited by fixed observation models that fail to capture the complex, non-linear, state-dependent dynamics of physiological signals.</div><div>To address this, we propose the Residual-Compensated Adaptive Kalman Filter (RCAKF), a novel hybrid framework. The RCAKF integrates a long short-term memory (LSTM) network to learn and correct structured, state-dependent errors in the observation model, alongside an adaptive noise estimator that dynamically adjusts for measurement uncertainty. This architecture enhances the classic Kalman filter with data-driven flexibility while maintaining its recursive structure and interpretability.</div><div>Evaluation was conducted on a controlled experimental dataset with 22 participants performing exercise and recovery under varied thermal conditions. Compared to five baseline models: extended Kalman filter (EKF: RMSE = 0.39 °C), the improved ECTemp model with a sigmoid observation function (ECTemp-S: RMSE = 0.40 °C), biphasic Kalman filter-based model (BKFB: RMSE = 0.48 °C), moving-average Kalman filter (MAKF: RMSE = 0.38 °C), and a standalone LSTM network (RMSE = 0.46 °C), RCAKF achieved the best accuracy with an RMSE of 0.31 °C.</div><div>By augmenting the Kalman filter with a learned residual correction and adaptive uncertainty, the RCAKF framework significantly enhances core temperature tracking from a single heart rate signal. Its accuracy and reliance on a single, common sensor make it a practical and promising solution for real-time deployment on wearable devices for safety monitoring.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 617-629"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145323893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of tissue conductivity uncertainty on the nerve activation thresholds in non-invasive electrical phrenic nerve stimulation","authors":"Laureen Wegert ,&nbsp;Luca Di Rienzo ,&nbsp;Lorenzo Codecasa ,&nbsp;Sicheng An ,&nbsp;Marek Ziolkowski ,&nbsp;Alexander Hunold ,&nbsp;Irene Lange ,&nbsp;Tim Kalla ,&nbsp;Jens Haueisen","doi":"10.1016/j.bbe.2025.11.003","DOIUrl":"10.1016/j.bbe.2025.11.003","url":null,"abstract":"<div><div>Non-invasive phrenic nerve stimulation can be used to overcome diaphragm insufficiency caused by mechanical ventilation. Detailed models and electromagnetic simulations are used to suggest appropriate stimulation parameters, but require accurate tissue properties. However, a wide range of electrical conductivity values is known from the literature. Here, we aim to perform an uncertainty analysis of the nerve activation threshold and the potential distribution along the phrenic nerve due to uncertain tissue conductivites.</div><div>We built a generalized polynomial chaos (gPC) model to calculate the phrenic nerve activation threshold. It was based on a reduced order model of a detailed anatomical finite element model of the neck including 13 tissue types to calculate the potential distribution, followed by a biophysiological nerve model. The tissue conductivity values investigated here were for the compartments of fat, muscle, nerve, and soft tissue. Their influence on the nerve activation threshold was investigated by changing conductivity values of the single tissues and all tissues at a time within a Monte Carlo analysis using the gPC model.</div><div>The phrenic nerve activation threshold varied between 33.8 mA and 46.9 mA for the combined variation of the conductivity values. Sobol indices and global sensitivity coefficients indicated the highest influence for muscle conductivity value, followed by soft tissue, fat, and nerve tissue.</div><div>Our results may have implications for understanding the experimentally observed variation in individual phrenic nerve activation thresholds affected by physiological and pathological conductivity changes. Accurate electric properties of muscle and soft tissue and detailed geometric representations should be considered in electromagnetic simulations.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 697-706"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145617673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel class of rank tests for high-dimensional data with an application to Alzheimer’s disease","authors":"Jan Kalina ,&nbsp;Jaromir Kukal ,&nbsp;Oldrich Vysata","doi":"10.1016/j.bbe.2025.10.005","DOIUrl":"10.1016/j.bbe.2025.10.005","url":null,"abstract":"<div><div>Electroencephalography (EEG) signals are widely used in neuroscience research and biomedical applications, particularly for comparative analyses between two cohorts: patients and control subjects. In EEG research, multivariate two-sample tests remain underused, while multiple comparison procedures are often misapplied as a substitute, leading to inadequate error control. Moreover, existing rank-based tests rely solely on Euclidean distances and lack robustness to outliers. The objective of this work is to develop and evaluate a new class of rank-based tests for high-dimensional data that employ robust Mahalanobis interpoint distances, and to demonstrate their practical value in the analysis of EEG signals. This class includes a version based on the MRWCD (minimum regularized weighted covariance determinant) estimator, which enhances the robustness of the Mahalanobis distances by mitigating the influence of outliers.</div><div>To illustrate the effectiveness of these tests, EEG data consisting of 1216 variables from 28 patients with Alzheimer’s disease and 146 healthy control individuals were analyzed. The results of multivariate tests reveal significant findings, which are also explored in the context of individual EEG channels and frequencies. Among the approaches tested, rank-based tests using the newly proposed interpoint distances, particularly in combination with the Cucconi test statistic, yield the strongest results. For the comparison between patients and controls, a <em>p</em>-value of 0.004 was obtained, which is below the significance level <span><math><mrow><mi>α</mi><mo>=</mo><mn>0.05</mn></mrow></math></span>, indicating a statistically significant difference.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 707-717"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145617670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reevaluating performance in c-VEP BCIs: The impact of calibration time","authors":"Víctor Martínez-Cagigal ,&nbsp;Eduardo Santamaría-Vázquez ,&nbsp;Sergio Pérez-Velasco ,&nbsp;Ana Martín-Fernández ,&nbsp;Roberto Hornero","doi":"10.1016/j.bbe.2025.10.006","DOIUrl":"10.1016/j.bbe.2025.10.006","url":null,"abstract":"<div><div>Code-modulated visual evoked potentials (c-VEP) have demonstrated high performance in non-invasive brain-computer interfaces (BCIs). Recently, research has begun to consider practical aspects such as visual comfort, where non-binary sequences and variations in the spatial frequency of stimuli play significant roles. However, calibration requirements remain underexplored in performance comparisons. This study aims to analyze a multi-variable tradeoff crucial to the practical application of c-VEP-based BCIs: decoding accuracy, decoding speed, and calibration time. Visual comfort is retrospectively evaluated using two pre-recorded datasets. Models were trained with increasing calibration cycles and tested across varying decoding times, depicting learning and decoding curves. The datasets comprised 32 healthy subjects, and featured different stimulus paradigms: plain non-binary stimuli and checkerboard-like binary stimuli with spatial frequency variations. Results showed that all conditions achieved over 97 % grand-averaged accuracy with sufficient calibration. However, a clear tradeoff emerged between calibration duration and performance. Achieving 95 % average accuracy within a 2 s decoding window required mean calibration durations of 28.7 ± 19.0 s for binary stimuli, or 148.7 ± 72.3 s for non-binary stimuli. The binary checkerboard-based condition with a spatial frequency of 1.2 c/º (C016) proved to be particularly effective, achieving over 95 % accuracy within 2 s decoding window using only 7.3 s of calibration, and reporting a significant improvement in visual comfort. A minimum calibration time of 1 min was considered essential to adequately estimate the brain response, critical in template-matching paradigms. In conclusion, achieving optimal c-VEP performance requires balancing calibration duration, decoding speed and accuracy, and visual comfort.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 685-696"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145519677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TRI-based heart rate variability parameterisation: advancing autonomic dysfunction assessment in diabetes and aging—A cross-sectional observational study","authors":"Shanglin Yang ,&nbsp;Yuyang Lin ,&nbsp;Xuwei Liao ,&nbsp;Jianjung Chen ,&nbsp;Hsientsai Wu","doi":"10.1016/j.bbe.2025.08.006","DOIUrl":"10.1016/j.bbe.2025.08.006","url":null,"abstract":"<div><div>This cross-sectional observational study introduces the T-R interval (TRI), a novel electrocardiographic parameter designed to improve heart rate variability (HRV) assessment in ageing and diabetic populations. Defined as the R-R interval (RRI) minus the heart rate-corrected RT interval (RTc), TRI incorporates both depolarisation and repolarisation phases of the cardiac cycle, thereby offering deeper insights into autonomic function. A total of 126 participants, including 58 individuals with type 2 diabetes mellitus and 68 healthy controls, were assessed using conventional HRV indices. These included the low-to-high frequency power ratio (LHR), the short-to-long variability ratio (SSR), and the baroreflex entropy index (BEI), all of which were calculated from both RRI and TRI data. TRI-based indices demonstrated superior sensitivity in detecting autonomic dysfunction. Significant group differences were observed for TRI-derived MSE_LS (mean difference = 0.205, 95 % CI: 0.093–0.317, <em>p</em> = 0.036), SSR (mean difference =  − 0.083, 95 % CI: −0.136–−0.029, <em>p</em> = 0.051), and BEI (mean difference = 0.205, 95 % CI: 0.093–0.318, <em>p</em> = 0.002), while their RRI-based equivalents did not reach statistical significance. ROC curve analysis showed improvements in the area under the curve (AUC) when TRI was used as the input parameter, with gains of 5.9 % for MSE_LS, 10.6 %for SSR, and 6.1 % for BEI. Logistic regression further identified TRI-based BEI as a protective factor against new-onset T2DM (OR = 0.058; 95 % CI: 0.009–0.378; <em>p</em> = 0.003). These findings suggest that TRI improves the diagnostic performance of HRV analysis and may support earlier detection of autonomic dysfunction, especially in clinical and wearable monitoring settings.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 581-592"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A morphometric lung model for evaluating lung aeration at birth","authors":"Chiara Veneroni ,&nbsp;Enrico Conca ,&nbsp;Davide Bizzotto ,&nbsp;Kenneth Lutchen ,&nbsp;Alberto Tosi ,&nbsp;Raffaele L. Dellacà","doi":"10.1016/j.bbe.2025.11.004","DOIUrl":"10.1016/j.bbe.2025.11.004","url":null,"abstract":"<div><h3>Background</h3><div>Lung aeration must rapidly develop at birth, but how to promote it without injuring the fragile lung is still unknown. Mathematical models simulating lung mechanics during this transition may help understand the underlying physiological mechanisms and design protective ventilation strategies. This study develops a morphologically-coherent computational lung model incorporating changing physical conditions during the transition from liquid-filled to gas-filled lungs.</div></div><div><h3>Methods</h3><div>We adapted a 3-D morphological model of the adult airway tree adjusting airway dimensions, lung volume, and lung tissue mechanical properties. Changes in resistance, inertia, and compliance during aeration were modeled by considering the differing properties of fetal fluid versus air. The capillary pressure at the liquid–air interface was computed using Laplace equation. Terminal airway diameters increased with lung volume due to airway-parenchymal interdependence. An integrated circuit simulator solved the entire network in the time domain.</div></div><div><h3>Results</h3><div>The air volume entering the model at different applied pressures increased exponentially with time. With 30 cmH₂O applied, lung volume reached total capacity after 15 s, matching lung aeration dynamics observed in animal models and human infants. In contrast, after the same time, at 15 cmH₂O, lung volume was slightly above functional residual capacity, and at 10 cmH₂O, it remained below.</div></div><div><h3>Conclusions</h3><div>The proposed in-silico newborn lung model simulates lung aeration at birth, allowing observation of the airway emptying sequence and the heterogeneity of aeration at each time point. Integrating this model with comprehensive acinar models may aid in defining protective resuscitation ventilation strategies for recruiting the lung minimizing risk of injuries.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 718-725"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145617672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-peak cyclic loading for evaluation of lower-limb prostheses","authors":"Zhaokun Zhang ,&nbsp;Wangrui Xu ,&nbsp;Hanyu Gan ,&nbsp;Chunlei K. Song ,&nbsp;Albert J. Shih","doi":"10.1016/j.bbe.2025.10.004","DOIUrl":"10.1016/j.bbe.2025.10.004","url":null,"abstract":"<div><div>Lower-limb prosthesis (LLP) is critical for the mobility and quality of life of amputees. Ensuring the reliability and durability of LLPs is essential to users’ safety, comfort, and mobility. While the current standard (ISO 10328) for the mechanical test of LLPs has served as a foundation, the sinusoidal cyclic loading method used for fatigue testing does not replicate the actual loading conditions on LLPs during a human walking gait. In normal walking, LLPs are subjected to a dual-peak loading condition with two distinct force peaks at the heel-strike and toe-off phases. Such a cyclic and dual-peak dynamic loading pattern on LLP is essential to test the durability of the LLP effectively and reliably. In this study, two simple and effective dual-peak cyclic loading test apparatuses are designed and built to evaluate the durability and functionality of LLPs. Two loading plates are used to contact the heel and toe of the prosthetic foot to simulate the dual-peak heel-strike and toe-off loadings between the foot and the ground. This dual-peak loading on the LLP is controlled and replicated by adjusting the positions of two loading plates and the actuator stroke to change the contact forces. Experimental results show that the proposed testing apparatuses and procedures can emulate the dual-peak axial loading of the LLP during normal walking gait, providing a more accurate testing method of the dynamic loading condition on LLPs than the current ISO standard.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 4","pages":"Pages 642-654"},"PeriodicalIF":6.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Viscoelastic modeling of optic nerve head biomechanics: Effects of intraocular and cerebrospinal fluid pressure","authors":"Alireza Karimi ,&nbsp;Reza Razaghi ,&nbsp;Seyed Mohammadali Rahmati ,&nbsp;J. Crawford Downs","doi":"10.1016/j.bbe.2025.05.008","DOIUrl":"10.1016/j.bbe.2025.05.008","url":null,"abstract":"<div><div>Although the optic nerve head (ONH) has demonstrated a significant viscoelastic response to changes in intraocular pressure (IOP), existing computational models of ONH biomechanics have yet to fully account for these viscoelastic properties. In this study, we introduce and evaluate a mesh-free beam-in-solid coupling algorithm to model the complex viscoelastic behavior of anisotropic collagen fibers within a viscoelastic scleral matrix. We also incorporated viscoelastic formulations for the retina, lamina cribrosa, and optic nerve to provide a more comprehensive understanding of ONH tissue mechanics. We compared the biomechanics of the ONH resulting from hyperelastic and viscoelastic scleral material formulations using an eye-specific finite element model of the posterior human eye. This model integrates the detailed 3D microstructure of the load-bearing lamina cribrosa, including interspersed laminar neural tissues, as well as the heterogeneous, anisotropic behavior of the collagenous sclera and pia. The viscoelastic material properties were validated against published experimental tensile tests of human scleral and retinal tissue samples. Simulations of ONH biomechanical responses were conducted by applying changes in IOP and cerebrospinal fluid pressure (CSFP) typical of body position transitions, such as moving from sitting to supine, over a 250 ms period. In both simulations, the ONH tissues exhibited greater stresses and strains in the supine position compared to sitting, as anticipated. The laminar surface showed posterior deformation (+6 µm) during the transition from sitting to supine when using the hyperelastic material model, whereas it deformed anteriorly (−5.7 µm) with the viscoelastic model. Furthermore, the radial scleral canal expansion at the anterior laminar insertion was significantly smaller in the viscoelastic formulation (9 µm) compared to the hyperelastic formulation (19.8 µm). All results aligned with experimental observations. While the stresses, strains, and deformations remained within physiological ranges for both models, there were substantial differences between the two formulations, particularly in terms of deformation. Improving the accuracy of material formulations in ONH models is expected to enhance our understanding of ONH biomechanics. However, further experimental validation is needed to confirm these results and strengthen their applicability.</div></div>","PeriodicalId":55381,"journal":{"name":"Biocybernetics and Biomedical Engineering","volume":"45 3","pages":"Pages 357-379"},"PeriodicalIF":5.3,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}