Medical Engineering & Physics最新文献_第8页

Medical devices: Materials, mechanics, and manufacturing 医疗器械：材料、机械和制造

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-18 DOI: 10.1016/j.medengphy.2025.104384

Sotiris Korossis, Vadim V. Silberschmidt

引用次数: 0

Morphological characterization of median nerve and transverse carpal ligament from ultrasound images using convolutional neural networks 利用卷积神经网络对超声图像中正中神经和腕横韧带的形态学表征

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-18 DOI: 10.1016/j.medengphy.2025.104383

Jocelyn L. Hawk , Shalon Walter , Xiaoxiao Sun , Zong-Ming Li

Objectives

The purpose of this study was to automatically segment and quantify the median nerve and carpal arch from ultrasound images using convolutional neural network (CNN).

Methods

A U-Net method based on CNN was implemented for median nerve and transverse carpal ligament segmentation from cross-sectional ultrasound images of the distal carpal tunnel. Median nerve and ligament were measured using the manual segmentations and model predictions. Model performance was evaluated using Dice score coefficient (DSC), recall, and precision. Model performance parameters and morphological parameters were compared between the healthy and carpal tunnel syndrome patients using Wilcoxon signed-rank test. The reliability of the morphological measurements from the predictions was assessed by calculating mean average error and the intra-class coefficient (ICC).

Results

The DSC, recall, and precision were 0.89 ± 0.81, 0.94 ± 0.04, and 0.86 ± 0.08 for healthy subjects, respectively, for median nerve segmentation; the corresponding values for patients were 0.81 ± 0.08, 0.86 ± 0.10, and 0.77 ± 0.11, respectively. For ligament segmentation, the DSC, recall, and precision were 0.87 ± 0.03, 0.88 ± 0.04, and 0.87 ± 0.05, respectively, for healthy subjects; the corresponding values for patients were 0.77 ± 0.10, 0.77 ± 0.12, and 0.77 ± 0.09, respectively. Acceptable to excellent agreement was found between morphological measurements calculated using manual segmentations and model predictions. The carpal tunnel syndrome patients had larger median nerve cross-sectional area and carpal arch height than the healthy subjects when measured from the model predictions (p < 0.05).

Conclusions

CNNs were used to automatically segment the median nerve and TCL with high accuracy. The model predictions provided reliable quantification of the carpal tunnel anatomy, demonstrating the potential diagnostic value using CNNs.

目的利用卷积神经网络（CNN）从超声图像中自动分割和量化正中神经和腕弓。方法采用基于CNN的U-Net方法对腕管远端超声横断面图像进行正中神经和腕横韧带分割。采用人工分割和模型预测对正中神经和韧带进行测量。模型性能评估使用骰子得分系数（DSC），召回率和精度。采用Wilcoxon sign -rank检验比较健康患者与腕管综合征患者的模型性能参数和形态学参数。通过计算平均误差和类内系数（ICC）来评估预测的形态学测量的可靠性。结果健康受试者正中神经分割的DSC、查全率和查准率分别为0.89±0.81、0.94±0.04和0.86±0.08；患者的相应值分别为0.81±0.08、0.86±0.10和0.77±0.11。健康受试者韧带分割的DSC、查全率和查准率分别为0.87±0.03、0.88±0.04和0.87±0.05；患者的相应值分别为0.77±0.10、0.77±0.12、0.77±0.09。在使用人工分割和模型预测计算的形态学测量之间发现了可接受的极好的一致性。腕管综合征患者的正中神经横截面积和腕弓高度均大于健康受试者(p <；0.05)。结论scnns能较好地自动分割正中神经和TCL神经。模型预测提供了可靠的腕管解剖定量，证明了使用cnn的潜在诊断价值。

{"title":"Morphological characterization of median nerve and transverse carpal ligament from ultrasound images using convolutional neural networks","authors":"Jocelyn L. Hawk , Shalon Walter , Xiaoxiao Sun , Zong-Ming Li","doi":"10.1016/j.medengphy.2025.104383","DOIUrl":"10.1016/j.medengphy.2025.104383","url":null,"abstract":"<div><h3>Objectives</h3><div>The purpose of this study was to automatically segment and quantify the median nerve and carpal arch from ultrasound images using convolutional neural network (CNN).</div></div><div><h3>Methods</h3><div>A U-Net method based on CNN was implemented for median nerve and transverse carpal ligament segmentation from cross-sectional ultrasound images of the distal carpal tunnel. Median nerve and ligament were measured using the manual segmentations and model predictions. Model performance was evaluated using Dice score coefficient (DSC), recall, and precision. Model performance parameters and morphological parameters were compared between the healthy and carpal tunnel syndrome patients using Wilcoxon signed-rank test. The reliability of the morphological measurements from the predictions was assessed by calculating mean average error and the intra-class coefficient (ICC).</div></div><div><h3>Results</h3><div>The DSC, recall, and precision were 0.89 ± 0.81, 0.94 ± 0.04, and 0.86 ± 0.08 for healthy subjects, respectively, for median nerve segmentation; the corresponding values for patients were 0.81 ± 0.08, 0.86 ± 0.10, and 0.77 ± 0.11, respectively. For ligament segmentation, the DSC, recall, and precision were 0.87 ± 0.03, 0.88 ± 0.04, and 0.87 ± 0.05, respectively, for healthy subjects; the corresponding values for patients were 0.77 ± 0.10, 0.77 ± 0.12, and 0.77 ± 0.09, respectively. Acceptable to excellent agreement was found between morphological measurements calculated using manual segmentations and model predictions. The carpal tunnel syndrome patients had larger median nerve cross-sectional area and carpal arch height than the healthy subjects when measured from the model predictions (p < 0.05).</div></div><div><h3>Conclusions</h3><div>CNNs were used to automatically segment the median nerve and TCL with high accuracy. The model predictions provided reliable quantification of the carpal tunnel anatomy, demonstrating the potential diagnostic value using CNNs.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"143 ","pages":"Article 104383"},"PeriodicalIF":1.7,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536023","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}

引用次数: 0

Exploring the neural mechanisms of alpha-band EEG neurofeedback using portable devices: A pre-post comparative study 利用便携式设备探索α波段脑电图神经反馈的神经机制：前后对比研究

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-11 DOI: 10.1016/j.medengphy.2025.104380

Xiaoyu Chen , Li Sui

Objective

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.

Methods

Sixteen healthy young adults (

M = 24.28 \pm 1.31

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.

Results

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.

Conclusion

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.

目的探讨利用便携式脑电图系统进行α波段神经反馈（NF）训练的神经机制，并评价其在实际应用中增强认知能力的可行性。方法16例健康青年（M=24.28±1.31岁）完成8组α波段NF训练。采用可穿戴式16通道设备采集训练前后的脑电信号。通过功率谱分析、源定位（sLORETA）和五个频段的功能连接分析来评估神经变化。结果，紧张导致theta， alpha， beta和gamma波段的功率增加。来源分析显示，低频电流密度下降，高频电流活动增加，这反映了神经处理效率的提高和认知网络参与的增强，这一点得到了之前研究的支持。功能连通性表明，与工作记忆有关的额叶、顶叶和枕叶区域的同步性较强。结论便携式α波段神经反馈训练可诱导多频段和脑网络的广泛神经调制，支持可穿戴脑电图系统用于无障碍认知训练的可行性。

{"title":"Exploring the neural mechanisms of alpha-band EEG neurofeedback using portable devices: A pre-post comparative study","authors":"Xiaoyu Chen , 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}

引用次数: 0

Effects of wall compliance on pulsatile flow in a full-scale, patient-specific cerebral aneurysm model: Particle image velocimetry experiments 在全尺寸患者特异性脑动脉瘤模型中，壁面顺应性对脉动血流的影响：粒子图像测速实验

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-10 DOI: 10.1016/j.medengphy.2025.104381

Ryuhei Yamaguchi , Muhamed Albadawi , Nadia Shaira Shafii , Atsushi Saito , Toshiyuki Nakata , Khalid M. Saqr , Hitomi Anzai , Makoto Ohta

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.

弹性脑动脉瘤的血流动力学由于影响每个动脉瘤的发生和发展的现象而变得复杂。血管因脉动血流而变形。然而，在一个幻影中，是否可以忽略对隔离墙的遵守尚不清楚。在我们之前的研究中，垂直于中位面的另一个平面上的流动结构没有得到明确。在这里提出的方法中，通过调整浸泡在浴缸中的周围流体，对刚性和弹性壁模型使用相同的模体。为此，全尺寸的动脉瘤假体是用有机硅弹性体制造的。研究了大脑中动脉分叉变形模型和非变形模型在正交平面上的血流动力学因素。采用二维粒子图像测速技术，测量了脉动流动过程中的流速、壁面剪切应力（WSS）、壁面剪切应力梯度（WSSG）和湍流动能（TKE）。总体而言，中位面WSSG小于对应垂直面WSSG。变形模型的TKE小于非变形模型的TKE。我们的结果阐明了动脉瘤壁顺应性对这些血流动力学因素的复杂影响。

{"title":"Effects of wall compliance on pulsatile flow in a full-scale, patient-specific cerebral aneurysm model: Particle image velocimetry experiments","authors":"Ryuhei Yamaguchi , Muhamed Albadawi , Nadia Shaira Shafii , Atsushi Saito , Toshiyuki Nakata , Khalid M. Saqr , Hitomi Anzai , 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}

引用次数: 0

Modelling and numerical solution of variable orifice flow meter for application of respiratory 呼吸用可变孔板流量计的建模与数值求解

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-07 DOI: 10.1016/j.medengphy.2025.104379

Rana K. Shamkhi , Muneer A. Ismael

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.

本文研究了用于机械通风机的可变孔板流量计（VOFM）的三维计算流体力学分析。分析采用了动态流固相互作用（FSI）方法，利用有限体积法（FVM）。采用两种湍流k-ω海表温度模型进行了全面的数值模拟。通过对柔性膜制作三角形孔板和圆形孔板的流动特性进行研究，验证了CFD方法的有效性。通过将数值结果与先前发表的实验数据进行比较，验证了柔性膜挠度、阻力系数和压降与质量流量的关系。结果表明，孔板的厚度和形状对压降和挠度的影响至关重要。值得注意的是，与三角形模型相比，圆形模型表现出更多的线性行为和更高的灵敏度。

引用次数: 0

An enhanced UHMWPE wear particle detection approach based on YOLOv9 基于YOLOv9的增强UHMWPE磨损颗粒检测方法

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-06 DOI: 10.1016/j.medengphy.2025.104377

Lingmeng Li , Mingzhen Deng , Steven Su , Richard M. Hall , J.L. Tipper

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.

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.

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.

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.

超高分子量聚乙烯（UHMWPE）已广泛应用于骨科和脊柱植入物的全关节置换术中。然而，对UHMWPE磨损颗粒的生物反应已被确定为炎症性滑膜炎和假体周围骨溶解的主要因素，这可能导致无菌性松动和长期植入失败。传统的UHMWPE磨损颗粒的人工检测和分类劳动强度大，耗时长，容易出现人为错误，需要发展自动化检测技术。本研究提出了一种新的基于深度学习的框架，用于检测超高分子量聚乙烯磨损颗粒，利用高分辨率场发射枪扫描电子显微镜（fg - sem）图像。该方法采用改进的YOLOv9目标检测模型，结合可编程梯度信息（PGI）和广义高效层聚合网络（GELAN），提高了小目标的定位和检测精度。此外，还集成了定制的焦损功能，以解决类不平衡问题，提高对亚微米和纳米级磨损颗粒的灵敏度。实验评估表明，我们提出的模型达到了84.0%的平均精度（mAP），比基线YOLOv5模型高出7.7%。此外，与主流的目标检测模型（如YOLOv8和Faster R-CNN）相比，我们的方法具有更高的检测精度和鲁棒性，特别是在识别复杂背景和重叠区域的磨损颗粒方面。除了开发先进的检测算法外，本研究还建立了一个专用的专家注释的UHMWPE磨损颗粒数据集，解决了骨科植入物研究中的一个关键空白。提出的框架为UHMWPE磨损颗粒的自动检测提供了可扩展、高精度和经济高效的解决方案，支持改进的植入物监测、骨溶解预防以及骨科和脊柱植入物评估的临床决策。

{"title":"An enhanced UHMWPE wear particle detection approach based on YOLOv9","authors":"Lingmeng Li , Mingzhen Deng , Steven Su , Richard M. Hall , 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}

引用次数: 0

Intra and inter-system reliability of a markerless motion capture system in different configurations during functional tasks: Implications for utility 功能任务中不同配置下无标记动作捕捉系统的内部和系统间可靠性：对实用性的影响

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-04 DOI: 10.1016/j.medengphy.2025.104375

Mark W. Lenhoff, Silvia Zanini, Gregory Chingas, Snehal Patel, Robert DiGiacomo, Howard J. Hillstrom

Background

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.

Research Question

Does a markerless motion capture system exhibit intra-device and inter-device reliability with an Intraclass Correlation Coefficient (ICC) > 0.70 during functional tasks?

Methods

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.

Results

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.

Significance

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 > 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.

无背景标记的运动捕捉比传统的基于标记的方法更快，但其可靠性尚未得到很好的验证。必须了解这项新技术的局限性，以确保其得到适当利用。无标记动作捕捉系统是否具有类内相关系数（ICC）的设备内和设备间可靠性？在功能性任务中0.70 ？方法要求20名被试蹲走三次，计算三种设备的测试-重测试（使用相同比例的骨骼模型的重复任务）和移除-替换（使用两个独立生成的骨骼模型的重复任务）设备内可靠性和设备间可靠性。在一个标准卷中配置了两个设备，在一个更大的卷中配置了一个设备。结果器械内可靠性方面，深蹲运动范围（ROM）测试-重测ICC平均为0.86，深蹲移除-替换ICC平均为0.74。walk ROM test-retest ICC平均为0.70，walk remove-replace ICC平均为0.72。对于标准体积中两个设备之间的设备间可靠性，蹲下时的平均ICC为0.82，行走时为0.72。将次优化配置的设备纳入三设备分析后，设备间的平均可靠性ICC在蹲下时降至0.55，在行走时降至0.46。更大的视场、次优的相机位置和远离视场中心的任务对DARI无标记动作捕捉系统提出了挑战。设备内和设备间的可靠性可达到ICC >级别；0.7使用优化设置的DARI无标记动作捕捉技术，但横向平面运动学表现出最弱的性能。最佳相机位置（即视野）对于可靠的结果至关重要。

{"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, Silvia Zanini, Gregory Chingas, Snehal Patel, Robert DiGiacomo, 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) > 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 > 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}

引用次数: 0

Gradient-driven pixel connectivity convolutional neural networks classification based on U-Net lung nodule segmentation 基于U-Net肺结节分割的梯度驱动像素连通性卷积神经网络分类

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-03 DOI: 10.1016/j.medengphy.2025.104376

Najeh Ahmed , Asma Ayadi , Imen Hammami

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, 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 features 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.

肺癌是一个重大的全球卫生问题，给卫生保健系统带来沉重负担。早期发现对改善患者预后至关重要。本研究提出了一种基于LUNA16数据集的基于深度学习的诊断辅助系统，用于从计算机断层扫描图像中早期发现和分类肺结节。该方法包括三个关键步骤。首先，使用U-Net卷积神经网络进行语义分割，然后进行特征提取和选择，然后使用另一个卷积神经网络进行分类。使用U-Net算法进行分割，准确率为99.16%，骰子相似系数为88.44%。对于感兴趣区域的结节和非结节的区分，分类准确率为90.36%。进一步分类对实性和磨砂玻璃结节的鉴别准确率为91.89%，良恶性的鉴别准确率为91.54%。这些结果证明了该模型在分类各种结节特征方面的鲁棒性。这些发现突出了该系统作为临床医生有价值的工具的潜力，有助于改善医疗保健结果和推进肺癌的诊断和治疗。

{"title":"Gradient-driven pixel connectivity convolutional neural networks classification based on U-Net lung nodule segmentation","authors":"Najeh Ahmed , Asma Ayadi , 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}

引用次数: 0

A coronary atherectomy system with a novel burr design for two-phase operation 一种新型冠状动脉粥样硬化切除系统，可用于两期手术

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-06-02 DOI: 10.1016/j.medengphy.2025.104374

Leilei Ma , Zhe Wang , Jiaqi Yang , Bin Shen , Yao Liu , Yihao Zheng , Yizhe Wu , Li Shen , Chenguang Li , Junbo Ge

Backgrounds

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.

Aims

To investigate the CAS mechanism and validate its efficacy and safety.

Methods

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.

Results

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.

Conclusions

This study demonstrated the efficacy and safety of CAS device with the novel two-phase burr design.

冠状动脉粥样硬化切除术系统（CAS）是一种新型的冠状动脉粥样硬化切除术系统，该系统采用了一种新型的毛刺，用于两阶段的动脉粥样硬化切除术：低速钻孔以穿过病变，高速旋转以获得腔隙增益，以去除动脉狭窄。目的探讨CAS的作用机制，验证其有效性和安全性。方法采用工程台架试验，对毛刺穿越时间、光增益、碎屑大小、温升和磨削力进行评价，并结合猪体内和离体研究。结果台架工程试验结果表明，CAS可将钙化管腔直径从0.4 mm扩大到1.7 mm，且碎屑尺寸、温升和磨削力相对较低且安全。在猪体内研究中，介质和内部弹性膜保持完整。在随访第0天切除动脉内膜，在随访第30天再生。数字减影血管造影、血检、心电图、解剖分析均未见异常。在离体研究中，通过在冠状动脉中插入斑块表面物（石墨），在管腔增益和安全性方面显示出类似的疗效。结论采用新型两相毛刺设计的CAS装置具有良好的安全性和有效性。

{"title":"A coronary atherectomy system with a novel burr design for two-phase operation","authors":"Leilei Ma , Zhe Wang , Jiaqi Yang , Bin Shen , Yao Liu , Yihao Zheng , Yizhe Wu , Li Shen , Chenguang Li , 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}

引用次数: 0

The optical performance of a 3D printed, titanium dioxide painted, Ganzfeld bowl 该光学性能为3D打印，二氧化钛涂漆，甘兹菲尔德碗

IF 1.7 4区医学 Q3 ENGINEERING, BIOMEDICAL

Medical Engineering & Physics

Pub Date : 2025-05-30 DOI: 10.1016/j.medengphy.2025.104372

Jesse Gale , Samuel Sartie , Patrick Dougherty , Callum Allen , Mark Bagley , Mirjam Münch , Simon Fraser

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.

三维（3D）打印的出现激发了创新的方法，使临床医生能够以低成本制造自己的医疗设备，这一过程被称为分布式制造。光刺激装置，如视觉电生理或瞳孔测量，需要物理和光学特性。在这里，我们测试了3D打印（熔融沉积建模，FDM）聚乳酸（PLA）表面是否能够表现出朗伯反射率，并测试了3D打印甘兹菲尔德碗作为积分球的行为。白色PLA可以透光，所以内部表面涂漆是必要的。我们测试了低成本二氧化钛（TiO2）基涂料的光谱和朗伯氏反射性能是否等同于专业的硫酸钡（BaSO4）涂料。我们的测量表明，我们的原型Ganzfeld与TiO2涂层均匀反射所有波长，并且具有90%的辐射均匀性，与其他已发表的设计相比要好。在许多司法管辖区，法规禁止自己动手制作医疗设备，但这些方法可能有助于感兴趣的临床医生为经伦理批准的研究创造设备，并帮助那些资源严重有限的人。

{"title":"The optical performance of a 3D printed, titanium dioxide painted, Ganzfeld bowl","authors":"Jesse Gale , Samuel Sartie , Patrick Dougherty , Callum Allen , Mark Bagley , Mirjam Münch , 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 (TiO<sub>2</sub>) based paint was equivalent to specialist barium sulphate (BaSO<sub>4</sub>) coating. Our measurements indicated that our prototype Ganzfeld with TiO<sub>2</sub> 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}

引用次数: 0