Biomedical Engineering Letters最新文献

{"title":"Wear and loosening in THA: results from a multidirectional simulator.","authors":"Atef Boulila, Lanouar Bouzid, Mahfoudh Ayadi","doi":"10.1007/s13534-025-00536-x","DOIUrl":"10.1007/s13534-025-00536-x","url":null,"abstract":"<p><p>Wear and loosening remain major concerns in total hip arthroplasty (THA), particularly in younger, more active patients who demand long-lasting implants. This study investigates wear behavior in three common prosthetic geometries and their material combinations using the TUNIS-3DOF hip simulator under physiological load conditions while adhering to ISO guidelines. A total of ultra-high molecular weight polyethylene (UHMWPE) acetabular cups were combined with stainless steel (SS316L), cobalt-chromium-molybdenum (CoCrMo), and zirconia (ZrO₂) femoral heads and subjected to six million gait cycles. All configurations exhibited a biphasic pattern of wear: a high wear \"running in\" phase, then a level linear regime. Zirconia heads had the lowest wear rates, while SS316L had the highest wear rates, especially exhibited in the early phases of testing. Both increased head diameter and decreased cup thickness both increased wear substantially, such changes commercially could be problematic regarding osteolysis and loosening. The change from abrasive to adhesive was related to radial stress, helped by analytical modelling. These results support the possibility of using reinforced or thicker cups, which may be made by incremental forming or additive methods, to strengthen implant longevity. This research assists in the process of maximizing THA designs to provide prolonged longevity and clinical results-especially in mechanically demanding patient populations.</p><p><strong>Graphical abstract: </strong></p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"539-560"},"PeriodicalIF":2.8,"publicationDate":"2026-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013905/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive conductors for organ-specific soft bioelectronic interfaces.","authors":"Il Ho Cho, Da Yeon Jang, Hye Jin Kim","doi":"10.1007/s13534-026-00549-0","DOIUrl":"10.1007/s13534-026-00549-0","url":null,"abstract":"<p><p>The realization of precision medicine relies on bioelectronics capable of reliably recording and modulating physiological signals across different organs. However, conventional interfaces based on rigid metals or silicon fail to conform to the soft and deformable nature of biological tissues, leading to signal degradation and long-term instability. These limitations highlight the need for organ-specific interfaces that reflect distinct electrical and mechanical requirements. In this review, we focus on adaptive conductor as key materials to address these challenges and synthesize recent progress in the field. We first compare the electrical and mechanical characteristics of representative organs-including the brain, heart, bladder, colon, and peripheral nerves-and assess the limitations of existing devices. We then outline the essential requirements and fabrication strategies of adaptive conductors, categorized into geometrical designs, nanocomposite engineering, and polymer engineering. Finally, we survey applications of adaptive conductors across multiple organs and highlight how organ-specific design principles can be translated into practical bioelectronics. By integrating recent advances into an organ-specific framework, this review provides a roadmap for the development of next-generation organ-specific soft bioelectronic interfaces.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"283-306"},"PeriodicalIF":2.8,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013874/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning-based multi-domain model for SOT composite score prediction using quiet standing COP data.","authors":"Yubin Cho, Oleksandr Yuhai, Gi Jung Im, Euyhyun Park, Seungu Shin, Ahnryul Choi, Joung Hwan Mun","doi":"10.1007/s13534-026-00555-2","DOIUrl":"https://doi.org/10.1007/s13534-026-00555-2","url":null,"abstract":"<p><p>The composite score (CS) obtained via the sensory organization test (SOT) serves as a key indicator of overall balance control. However, traditional assessment methods require expensive instrumentation, ample physical space, and multiple assessment conditions, thereby restricting their accessibility. To overcome these limitations, we developed a machine learning-based multi-domain model that predicts CS directly from quiet standing center of pressure (COP) data. A cohort of 302 participants completed SOT assessments, and their quiet standing COP signals were used for both model training and evaluation. Our model incorporates both time-demographic and frequency-domain features into a comprehensive feature set, providing a more holistic representation of postural control when compared with single-domain models. The model demonstrated strong predictive performance with R² = 0.990, RMSE = 0.632, and MAE = 0.338, offering a significant improvement over single-domain models (<i>p</i> < 0.001). These results indicate that applying machine learning to quiet standing COP data can yield highly accurate CS estimates, presenting an efficient and accessible method for balance assessment with potential applications in fall-risk evaluation, rehabilitation, and monitoring of disease progression.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 4","pages":"945-955"},"PeriodicalIF":3.4,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13476208/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148765696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anomaly detection in brain MRI: a comprehensive review.","authors":"Jihun Kim, Youmin Shin","doi":"10.1007/s13534-026-00551-6","DOIUrl":"10.1007/s13534-026-00551-6","url":null,"abstract":"<p><p>Magnetic resonance imaging (MRI) plays a central role in diagnosing neurological diseases, offering non-invasive, high-resolution views of brain anatomy. However, manual interpretation remains labor-intensive and subject to variability, particularly when detecting subtle or diffuse abnormalities. The growing volume of imaging data and limited availability of expert annotations have driven interest in artificial intelligence (AI)-based automation. Traditional supervised learning in neuroimaging demand large, annotated datasets and often struggle to generalize due to disease heterogeneity. Anomaly detection has gained attention as a scalable alternative: it models normal brain anatomy and flags deviations as potential abnormalities-without relying on labor-intensive, expert-labeled data. Because brain neuroscience is inherently complex, anomaly detection offers distinct promise in neuroimaging. In this review, we map the field of brain MRI anomaly detection across traditional statistics, classical machine learning (ML), and contemporary deep learning. We organize deep-learning work into three paradigms-reconstruction, generative, and self-supervised-highlighting their core assumptions, advantages, and caveats. Even with recent advances, critical challenges persist-including high false positive rates, unclear definitions of abnormality, limited interpretability, and vulnerability to domain shifts. To address these issues, emerging strategies such as hybrid learning, multimodal integration, and biologically grounded metrics (e.g., brain age gap) show promise in improving robustness and clinical relevance. We conclude with a research agenda for developing generalizable and interpretable AI systems that integrate into real-world neuroimaging workflows. We intend this review to serve as a practical and comprehensive guide for researchers and clinicians advancing reliable, scalable brain-MRI anomaly detection.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s13534-026-00551-6.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"369-385"},"PeriodicalIF":2.8,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013746/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PPG-AFNet: a lightweight and intelligible network for atrial fibrillation identification using photoplethysmography signals.","authors":"Preeti P Ghasad, Bhupendra Tiwari, Vipin Kamble, Prathamesh Kamble","doi":"10.1007/s13534-026-00556-1","DOIUrl":"https://doi.org/10.1007/s13534-026-00556-1","url":null,"abstract":"<p><p>Atrial fibrillation (AF) is a rapid and irregular heartbeat condition that occurs due to abnormal electrical pathways in the upper chambers of the heart. Although electrocardiogram (ECG) is the gold standard for AF detection, recently several studies have been performed that demonstrate the effectiveness of AF detection using photoplethysmography (PPG) signals. Although these approaches have claimed higher accuracies, they are limited by complex preprocessing, heavier model weights, and complex architectures, and require numerous training samples to achieve higher accuracies. In this paper, we present a lightweight PPG-based AF detection technique. The proposed approach utilizes scalograms to effectively capture subtle rhythm changes in the PPG signals. These scalograms are then fed to a custom, lightweight, intelligible neural network PPG-AFNet for AF detection. The proposed technique is capable of achieving superior accuracy of 99.21% for training on as few as 960 images, making it suitable for situations where data availability is limited. Consistent performance was observed with 10-fold cross-validation across the set of experiments, outperforming all existing state-of-the-art techniques on a public MIMIC Perform dataset. The model is also explainable using interpretable saliency maps for enhanced visual interpretability. The model offers a reduced set of trainable parameters without sacrificing performance, which makes it suitable for deployment in embedded systems with limited resources. Also, the proposed model performs consistently even for a limited set of data.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 4","pages":"957-968"},"PeriodicalIF":3.4,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13476422/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148765311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative and visual evaluation of dynamic isotropy in dual-axis random positioning machine (RPM) or clinostat for ground-based microgravity simulation.","authors":"Seungkwan Cho, Taehyun Lee, Migyo Shin, Doyong Kim, Tack-Joong Kim, Insu Park, Sangwoo Lee, Han Sung Kim","doi":"10.1007/s13534-026-00553-4","DOIUrl":"10.1007/s13534-026-00553-4","url":null,"abstract":"<p><p>Microgravity profoundly influences cellular morphology and function, yet ground-based simulation requires systems capable of randomizing the gravity vector. A dual-axis rotating machine (RM), such as a clinostat and random positioning machine (RPM), achieves quasi-isotropic gravitational averaging, but its quantitative optimization remains unclear. Here, a computational-experimental framework was established to evaluate dynamic isotropy of a dual-axis RM. Gravity vector trajectories were simulated across rotation ratios, and five metrics-Spherical Coverage (C), Cumulative Bias (H), Normalized Shannon Entropy (H/Hₘₐₓ), Mean Resultant Length (R), and Degree of Gravity Dispersion (DGD)-were integrated into an isotropy index (Sₒₚₜ). The isotropy peaked within an asynchronous range (4.0:3.8, 4.0:3.6, and 4.0:3.4 rpm), where gravity vectors exhibited uniform spherical coverage and minimal bias. To further assess the influence of rotational strength beyond the rotational ratio, an additional experiment was conducted using Huh7 hepatocellular carcinoma spheroids. Under high-speed random rotation (~ 4.0 rpm), cells formed compact, circular spheroids, whereas low-speed (~ 1.0 rpm) or static cultures produced irregular aggregates. These findings indicate that not only the ratio between dual-axis rotations but also the absolute rotational intensity critically affects isotropy and cellular morphogenesis under simulated microgravity. This integrative framework establishes a quantitative foundation for optimizing dual-axis rotating machines.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"561-572"},"PeriodicalIF":2.8,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013749/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Multi-perception fusion using shared-control method for brain-mobile robot.","authors":"Chenyang Wang, Mengfan Li, Pengfei Zhang, Ziqi Zhang, Fuyong Wang, Fei Kang","doi":"10.1007/s13534-026-00550-7","DOIUrl":"10.1007/s13534-026-00550-7","url":null,"abstract":"<p><p>For human-robot collaboration, brain-computer interface is promising to express human perception to improve the adaptability of human-robot collaboration in complex environments. In this study, a multi-perception fusion using shared control method (MPF-SC) is proposed to accurately integrate human perception and robot perception. This MPF-SC is applied in brain-controlled mobile robots to accomplish navigation and obstacle avoidance in complex terrain with multiple undetectable obstacles. The MPF-SC establishes a mapping relationship between visual stimulus interface and environment by computer vision, and utilizes a grid costmap to describe the human perception. It integrates EEG and EMG signals with user intent to dynamically adjust the grid costmap, mapping obstacle regions and integrating robot navigation to jointly accomplish driving tasks-with the aim of achieving human-machine shared perception. Sixteen subjects participated in an online obstacle avoidance experiment and compared the performance of the proposed method with two traditional methods. The research results show that the MPF-SC can generate smoother trajectories, achieve a significantly reduced collision rate during navigation, and significantly enhance user comfort. The MPF-SC based on brain-computer interface, fully leverages human anticipation of risks and the robot's perception of obstacle environments, demonstrating that bilateral intelligence is capable of adapting to increasingly complex environments, thereby offering a novel avenue and intuitive avenue for human-machine shared control.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 3","pages":"781-798"},"PeriodicalIF":3.4,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129184/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the impact of the water content of hydrophobic intraocular lenses on visual quality.","authors":"Jungmin Kim, Young-Sik Yoo, Jinheung Park, Woong-Joo Whang, Dae Yu Kim","doi":"10.1007/s13534-025-00528-x","DOIUrl":"10.1007/s13534-025-00528-x","url":null,"abstract":"<p><p>The impact of the water content of hydrophobic intraocular lenses (IOLs) on visual quality remains unclear. This study investigated how the water content influenced photic phenomena. Optical bench studies were conducted to compare two hydrophobic trifocal IOLs: PanOptix® (low-water content IOL) and Clareon® PanOptix® (high-water content IOL). Modulation transfer function (MTF) measurements were used to evaluate optical quality, while point spread function (PSF) images were used to evaluate photic phenomena. To validate the optical bench results, a retrospective observational case series study was conducted using medical records for 85 eyes from 85 patients (PanOptix®, n = 38; Clareon® PanOptix®, n = 47). Postoperative visual outcomes were evaluated two months after the operation using a defocus curve for uncorrected visual acuity and contrast sensitivity (CS) with and without glare. Subjective satisfaction regarding spectacle independence and dysphotopsia was evaluated using a questionnaire. The optical bench study showed that the high-water content IOL exhibited a 6.16% smaller glare diameter in near-vision PSF analysis, and slightly higher MTF values at near distances. The clinical study supported these results, showing that the high-water content IOL provided better uncorrected visual acuity (<i>P</i> < 0.05) and spectacle independence (<i>P</i> = 0.016) at near distances. Additionally, the high-water content IOL showed higher contrast sensitivity with glare at 6.3° (<i>P</i> = 0.040) and 4° (<i>P</i> = 0.018). Hydrophobic IOLs with a higher water content improved contrast sensitivity and subjective satisfaction by reducing glistening and minimizing photic phenomena.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"451-462"},"PeriodicalIF":2.8,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013792/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced intraparietal phase-lag synchronization in the high-gamma band during retention of visuospatial working memory.","authors":"Jimin Park, Sangjun Lee, Seonghun Park, Chany Lee","doi":"10.1007/s13534-025-00547-8","DOIUrl":"10.1007/s13534-025-00547-8","url":null,"abstract":"<p><p>Although zero-phase lag between cortical regions has been generally regarded as the optimal state, it has also been suggested that a non-zero phase delay of electroencephalography (EEG) signals in the gamma frequency band between bilateral parietal areas may have a significant meaning. Indeed, the phase delays of the gamma band between the cortical regions are reportedly associated with the direction of communication between the regions. In this study, we aimed to demonstrate synchrony with phase lag between cortical regions involved in visuospatial working memory (VWM) performance. We used EEG to compute the weighted phase lag index (wPLI) from the EEG signals concurrently recorded during the VWM task. An increase in wPLI value between the electrodes positioned over the bilateral parietal areas was observed during the VWM task. The wPLI values positively correlated with the lateralization index (LI) between the left and right visual hemifields. Furthermore, event-related desynchronization of gamma band activity is observed when wPLI peaked. Our findings suggest that phase lagged synchronization of high gamma band over bilateral parietal areas may reflect which information to prioritize during processing of VWM.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 3","pages":"759-767"},"PeriodicalIF":3.4,"publicationDate":"2026-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129030/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Data augmentation method for computer-aided diagnosis using specular reflection.","authors":"Youmin Shin, Jeonga Seol, Changwoo Lee, Jung Kim, Jinwook Choi, Jinbae Park, Soonwhan Kang, Gyuseon Song, Jung Ho Bae, Young-Gon Kim","doi":"10.1007/s13534-025-00533-0","DOIUrl":"10.1007/s13534-025-00533-0","url":null,"abstract":"<p><p>Colorectal cancer (CRC) is a significant global health challenge, emphasizing the importance of effective screening by applying methods like colonoscopy. While advanced imaging technologies, such as narrow-band imaging (NBI), allow real-time optical diagnosis of colon polyps, variations in endoscopist skills and unnecessary polypectomy underscore the need for artificial intelligence applications, particularly deep learning (DL) in computer-aided polyp detection and diagnosis (CADe and CADx). This study developed and investigated a data augmentation technique using specular reflection (SR) to enhance the robustness and performance of DL models tailored explicitly for CADx in colonoscopy. This SR augmentation method included SR generation and inpainting integrated into conventional augmentation techniques. We utilized two DL architectures: a convolutional neural network and a vision transformer. Stress tests, under varying data usage ratios using a dataset of 2,616 NBI images, revealed the robustness of SR augmentation, especially in scenarios with limited training data, highlighting its superiority over other methods. SR augmentation effectively improved model accuracy, particularly in scenarios with limited data, supporting its practical implementation in real-world colonoscopy environments. The findings emphasize the significance of domain-specific data augmentation techniques to support DL application in colonoscopy imaging for more reliable and accurate CADx systems for colon polyps.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s13534-025-00533-0.</p>","PeriodicalId":46898,"journal":{"name":"Biomedical Engineering Letters","volume":"16 2","pages":"493-505"},"PeriodicalIF":3.4,"publicationDate":"2026-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13013768/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}