Medical Engineering & Physics最新文献

{"title":"Exploring the neural mechanisms of alpha-band EEG neurofeedback using portable devices: A pre-post comparative study","authors":"Xiaoyu Chen ,&nbsp;Li Sui","doi":"10.1016/j.medengphy.2025.104380","DOIUrl":"10.1016/j.medengphy.2025.104380","url":null,"abstract":"<div><h3>Objective</h3><div>This study aimed to clarify the neural mechanisms of alpha-band neurofeedback (NF) training using a portable EEG system and to evaluate its feasibility for cognitive enhancement in practical settings.</div></div><div><h3>Methods</h3><div>Sixteen healthy young adults (<span><math><mi>M</mi><mo>=</mo><mn>24.28</mn><mo>±</mo><mn>1.31</mn></math></span> years) completed eight sessions of alpha-band NF training. EEG signals were collected before and after training with a wearable 16-channel device. Neural changes were assessed using power spectral analysis, source localization (sLORETA), and functional connectivity analysis across five frequency bands.</div></div><div><h3>Results</h3><div>Training led to increased power in theta, alpha, beta, and gamma bands. Source analysis showed decreased current density in lower frequencies and increased activity in higher bands, reflecting a shift toward more efficient neural processing and enhanced cognitive network engagement, as supported by previous studies. Functional connectivity revealed stronger synchronization among frontal, parietal, and occipital regions involved in working memory.</div></div><div><h3>Conclusion</h3><div>Portable alpha-band neurofeedback training induces widespread neural modulation across multiple frequency bands and brain networks, supporting the feasibility of wearable EEG systems for accessible cognitive training.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104380"},"PeriodicalIF":1.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of wall compliance on pulsatile flow in a full-scale, patient-specific cerebral aneurysm model: Particle image velocimetry experiments","authors":"Ryuhei Yamaguchi ,&nbsp;Muhamed Albadawi ,&nbsp;Nadia Shaira Shafii ,&nbsp;Atsushi Saito ,&nbsp;Toshiyuki Nakata ,&nbsp;Khalid M. Saqr ,&nbsp;Hitomi Anzai ,&nbsp;Makoto Ohta","doi":"10.1016/j.medengphy.2025.104381","DOIUrl":"10.1016/j.medengphy.2025.104381","url":null,"abstract":"<div><div>The hemodynamics of elastic cerebral aneurysms are complicated by phenomena that affect the initiation and the progress of each aneurysm. The blood vessel deforms with pulsatile flow. In a phantom, however, it remains unclear whether the wall compliance can be neglected. In our previous study, the flow structure at another plane oriented perpendicular to the median plane was not clarified. In the approach presented here, an identical phantom is used for both the rigid and elastic wall models by adjusting the surrounding fluid when immersed in a bath. For this purpose, the full-scale phantom of an aneurysm was fabricated using a silicone elastomer. The hemodynamic factors at the orthogonal planes in the non-deformable and deformable models of the bifurcation in the middle cerebral artery were examined. Using two-dimensional particle image velocimetry, the flow velocity, the wall shear stress (WSS), the WSS gradient (WSSG), and the turbulent kinetic energy (TKE) were measured during pulsatile flow. Overall, the WSSG at the median plane is smaller than that at corresponding perpendicular plane. Additionally, the TKE in the deformable model is smaller than that in the non-deformable model. Our results have clarified the complex effects of aneurysm wall compliance on these hemodynamic factors.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104381"},"PeriodicalIF":1.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling and numerical solution of variable orifice flow meter for application of respiratory","authors":"Rana K. Shamkhi ,&nbsp;Muneer A. Ismael","doi":"10.1016/j.medengphy.2025.104379","DOIUrl":"10.1016/j.medengphy.2025.104379","url":null,"abstract":"<div><div>This study investigates three-dimensional computational fluid dynamics (CFD) analysis related to Variable Orifice Flowmeters (VOFM) used in mechanical ventilators. The analysis employed a dynamic fluid-structure interaction (FSI) approach, utilizing the finite volume method (FVM). A comprehensive numerical simulation was performed using two turbulence k-ω SST model. The CFD methodology was validated by examining the flow characteristics of flexible membranes making triangular and circular orifice plates. Validation was achieved by comparing the numerical results with previously published experimental data, revealing several high correlation factors that describe the deflection of the flexible membrane, drag coefficient, and pressure drop in relation to the mass flowrate. The findings indicate that both the thickness and shape of the orifice play a crucial role in influencing pressure drop and deflection. Notably, the circular model exhibits more linear behaviour and greater sensitivity compared to the triangular model.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104379"},"PeriodicalIF":1.7,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An enhanced UHMWPE wear particle detection approach based on YOLOv9","authors":"Lingmeng Li ,&nbsp;Mingzhen Deng ,&nbsp;Steven Su ,&nbsp;Richard M. Hall ,&nbsp;J.L. Tipper","doi":"10.1016/j.medengphy.2025.104377","DOIUrl":"10.1016/j.medengphy.2025.104377","url":null,"abstract":"<div><div>Ultra-high molecular weight polyethylene (UHMWPE) has been widely used in total joint arthroplasty for orthopedic and spinal implants. However, the biological response to UHMWPE wear particles has been identified as a major contributor to inflammatory synovitis and periprosthetic osteolysis, which could lead to aseptic loosening and long-term implant failure. Traditional manual detection and classification of UHMWPE wear particles are labor-intensive, time-consuming, and prone to human error, which requires the development of automated detection techniques.</div><div>This study proposes a novel deep learning-based framework for detecting UHMWPE wear particles, utilizing high-resolution field emission gun-scanning electron microscopy (FEG-SEM) images. The proposed approach employs an enhanced YOLOv9 object detection model, incorporating programmable gradient information (PGI) and generalized efficient layer aggregation networks (GELAN) to improve the localization and detection accuracy of small objects. Additionally, a customized Focal Loss function is integrated to address class imbalance and enhance sensitivity to submicron and nanoscale wear particles.</div><div>Experimental evaluations demonstrate that our proposed model achieves a mean average precision (mAP) of 84.0%, outperforming the baseline YOLOv5 model by 7.7%. Furthermore, compared to mainstream object detection models such as YOLOv8 and Faster R-CNN, our approach exhibits superior detection accuracy and robustness, particularly in identifying wear particles in complex backgrounds and overlapping regions.</div><div>In addition to developing an advanced detection algorithm, this study establishes a dedicated and expert-annotated UHMWPE wear particle dataset, addressing a critical gap in orthopedic implant research. The proposed framework provides a scalable, high-precision, and cost-effective solution for the automated detection of UHMWPE wear particles, supporting improved implant monitoring, osteolysis prevention, and clinical decision-making in orthopedic and spinal implant evaluations.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104377"},"PeriodicalIF":1.7,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intra and inter-system reliability of a markerless motion capture system in different configurations during functional tasks: Implications for utility","authors":"Mark W. Lenhoff,&nbsp;Silvia Zanini,&nbsp;Gregory Chingas,&nbsp;Snehal Patel,&nbsp;Robert DiGiacomo,&nbsp;Howard J. Hillstrom","doi":"10.1016/j.medengphy.2025.104375","DOIUrl":"10.1016/j.medengphy.2025.104375","url":null,"abstract":"<div><h3>Background</h3><div>Markerless motion capture is faster than a traditional marker-based method, but its reliability is not well established. The limitations of this new technology must be understood to ensure its appropriate utilization.</div></div><div><h3>Research Question</h3><div>Does a markerless motion capture system exhibit intra-device and inter-device reliability with an Intraclass Correlation Coefficient (ICC) &gt; 0.70 during functional tasks?</div></div><div><h3>Methods</h3><div>Twenty test subjects were asked to squat and walk three times to compute the test-retest (repeated task with the same scaled skeletal model applied) and remove-replace (repeated task with two independently generated skeletal models applied) intra-device reliability for each of three devices and the inter-device reliability between the devices. Two devices were configured in a standard volume, and one device was configured sub-optimally in a larger volume.</div></div><div><h3>Results</h3><div>For intra-device reliability, the average squat range of motion (ROM) test-retest ICC was 0.86 and average squat remove-replace ICC was 0.74. The average walk ROM test-retest ICC was 0.70 and the average walk remove-replace ICC was 0.72. For inter-device reliability between the two devices in the standard volume, the average ICC was 0.82 for squat and 0.72 for walk. With the sub-optimally configured device included for a three-device analysis the average inter-device reliability ICC dropped to 0.55 for squat and 0.46 for walk.</div></div><div><h3>Significance</h3><div>Larger field of view, suboptimal camera placement and tasks performed away from the center of the field of view presented challenges to the DARI markerless mocap system. Intra-device and inter-device reliability can achieve a level of ICC &gt; 0.7 using DARI markerless mocap technology using an optimized setup, but the transverse plane kinematics exhibit the weakest performance. Optimal camera placement (i.e., field of view) is critical for reliable results.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104375"},"PeriodicalIF":1.7,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gradient-driven pixel connectivity convolutional neural networks classification based on U-Net lung nodule segmentation","authors":"Najeh Ahmed ,&nbsp;Asma Ayadi ,&nbsp;Imen Hammami","doi":"10.1016/j.medengphy.2025.104376","DOIUrl":"10.1016/j.medengphy.2025.104376","url":null,"abstract":"<div><div>Lung cancer is a significant global health issue, heavily burdening healthcare systems. Early detection is crucial for improving patient outcomes. This study proposes a diagnostic aid system for the early detection and classification of lung nodules from Computed Tomography images using deep learning<del>,</del> based on the LUNA16 Dataset. The methodology involves three key steps. Initially, a U-Net convolutional neural network is used for semantic segmentation, followed by feature<del>s</del> extraction and selection, which are subsequently used in classification with another convolutional neural network. The segmentation using the U-Net algorithm achieved an accuracy of 99.16 % and a Dice Similarity Coefficient of 88.44 %. For distinguishing between nodules and non-nodules in regions of interest, the classification accuracy was 90.36 %. Further classification achieved 91.89 % accuracy in differentiating solid and ground glass nodules and 91.54 % in distinguishing between benign and malignant ones. These results demonstrate the model's robust performance in categorizing various nodule characteristics. These findings highlight the potential of the proposed system as a valuable tool for clinicians, contributing to improved healthcare outcomes and advancing lung cancer diagnosis and treatment.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104376"},"PeriodicalIF":1.7,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A coronary atherectomy system with a novel burr design for two-phase operation","authors":"Leilei Ma ,&nbsp;Zhe Wang ,&nbsp;Jiaqi Yang ,&nbsp;Bin Shen ,&nbsp;Yao Liu ,&nbsp;Yihao Zheng ,&nbsp;Yizhe Wu ,&nbsp;Li Shen ,&nbsp;Chenguang Li ,&nbsp;Junbo Ge","doi":"10.1016/j.medengphy.2025.104374","DOIUrl":"10.1016/j.medengphy.2025.104374","url":null,"abstract":"<div><h3>Backgrounds</h3><div>A coronary atherectomy system (CAS) was developed with a novel burr designed for a two-phase atherectomy procedure: low-speed drilling for lesion crossing and high-speed orbiting to achieve luminal gain, to removal the stenosis in artery.</div></div><div><h3>Aims</h3><div>To investigate the CAS mechanism and validate its efficacy and safety.</div></div><div><h3>Methods</h3><div>Engineering bench-top testings were conducted to evaluate the burr crossing time, luminal gain, debris size, temperature rise, and grinding force together with in-vivo and ex-vivo swine studies.</div></div><div><h3>Results</h3><div>The bench-top engineering testing results showed that the CAS can expand the calcified lumen diameter from 0.4 to 1.7 mm and the debris size, temperature rise, and grinding force were relatively low and safe. In the in-vivo swine study, the media and internal elastic membrane remained intact. The intima of the artery was removed at the 0-day follow-up and re-growthed at the 30-day follow-up. No abnormal phenomenon in the digital subtraction angiography, blood testing, ECG, and anatomy analysis were found. The ex-vivo study, by inserting a plaque surragate (graphite) into the coronary artery, showed similar efficacy in luminal gain and safety.</div></div><div><h3>Conclusions</h3><div>This study demonstrated the efficacy and safety of CAS device with the novel two-phase burr design.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104374"},"PeriodicalIF":1.7,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144280679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The optical performance of a 3D printed, titanium dioxide painted, Ganzfeld bowl","authors":"Jesse Gale ,&nbsp;Samuel Sartie ,&nbsp;Patrick Dougherty ,&nbsp;Callum Allen ,&nbsp;Mark Bagley ,&nbsp;Mirjam Münch ,&nbsp;Simon Fraser","doi":"10.1016/j.medengphy.2025.104372","DOIUrl":"10.1016/j.medengphy.2025.104372","url":null,"abstract":"<div><div>The emergence of three dimensional (3D) printing has inspired creative ways to enable clinicians to make their own medical devices at low cost, a process called distributed manufacture. Devices for light stimulation, such as for visual electrophysiology or pupillometry, require both physical and optical properties. Here we tested whether a 3D printed (fused deposition modelling, FDM) poly-lactic acid (PLA) surface can exhibit Lambertian reflectance, and tested the behaviour of a 3D printed Ganzfeld bowl as an integrating sphere. White PLA transmits light, so a painted inside surface was necessary. We tested whether the spectral and Lambertian reflecting properties of low cost titanium dioxide (TiO₂) based paint was equivalent to specialist barium sulphate (BaSO₄) coating. Our measurements indicated that our prototype Ganzfeld with TiO₂ coating reflected all wavelengths equally and had radiance uniformity of 90 % which compared well to other published designs. In many jurisdictions regulation prevents a do-it-yourself approach to medical devices, but these approaches might facilitate interested clinicians to create devices for ethically approved research and assist those with severe resource limitations.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104372"},"PeriodicalIF":1.7,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Four-dimensional flow magnetic resonance imaging assessment of left ventricular hemodynamics in transplanted hearts with good postoperative course","authors":"Tomohiro Otani ,&nbsp;Seiko Ide ,&nbsp;Yuya Mashitani ,&nbsp;Yasushi Sakata ,&nbsp;Shigeo Wada","doi":"10.1016/j.medengphy.2025.104373","DOIUrl":"10.1016/j.medengphy.2025.104373","url":null,"abstract":"<div><div>Heart transplantation (HTx) is an established treatment for patients with advanced heart failure, although postoperative rejection responses hamper favorable long-term treatment outcomes. Medical imaging is a non-invasive diagnostic modality that can provide attractive insights into cardiac physiology for HTx, including morphological characteristics and cardiac hemodynamics. This study aimed to achieve a basic understanding of left ventricular (LV) hemodynamics in patients with good treatment outcomes following HTx. Specifically, four-dimensional magnetic resonance imaging was performed on 10 patients with a good postoperative course following HTx and 24 controls without a prior history of heart diseases nor HTx. LV hemodynamics were evaluated from the LV flow kinetic energy. We found that LV volumetric functions and kinetic energy ranges were not significantly different between the HTx and control groups, supporting good efficacy of HTx. Nevertheless, a temporal increase in the kinetic energy in late diastole owing to atrial contraction was present in the control group but absent in the HTx group except for one HTx patient. These findings raise the need of further evaluation of cardiac hemodynamics and the pathophysiology of HTx patients even within normal ranges of volumetric and flow transport functions.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104373"},"PeriodicalIF":1.7,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144222043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of mechanical stimuli on bone cells for regenerative medicine: A review of recent experimental and computational methods","authors":"Emilie Wiedemann-Fodé ,&nbsp;Jessica Schiavi-Tritz ,&nbsp;Halima Kerdjoudj ,&nbsp;Cédric Laurent","doi":"10.1016/j.medengphy.2025.104369","DOIUrl":"10.1016/j.medengphy.2025.104369","url":null,"abstract":"<div><div>Mechanobiology integrates biological and mechanical cues to provide a comprehensive understanding of how physical forces influence tissue regeneration, specifically focusing on bone growth and repair. This review presents a comprehensive overview of the latest developments in bone mechanobiology and highlights the remaining scientific and methodological challenges. Following a brief presentation of the challenges facing cell therapy, and in particular the application of different types of mechanical stimuli, the article examines these various processes on cells and tissues such as compressors and bioreactors operating at low frequencies (in the Hz range). Special attention is given to cutting-edge ultrasound techniques, such as the LIPUS method with MHz frequencies and low intensities ranging from 0.5 to 100 mW/cm², and with an emphasis on the emerging application of acoustic levitation with frequencies ranging from 340 kHz to 2.12 MHz permitting non-invasive manipulation of cells and tissues in biological research, with initial beneficial results in cell therapy. Lastly, the review offers a detailed analysis of multi-scale and multi-physics <em>in silico</em> approaches that may contribute to interpret the obtained experimental results. Agent-based models capture the discrete behaviour of individual cells, while continuum models describe tissue mechanics though averaged properties, offering complementary approaches to study complex mechanobiological phenomena. Such approaches hold the potential to drive transformative advances in bone regeneration medicine, providing a roadmap for future research.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"142 ","pages":"Article 104369"},"PeriodicalIF":1.7,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}