Annals of Biomedical Engineering最新文献

{"title":"Multiscale Entropy Reveals Reduced Airflow Complexity in Chronic Obstructive Pulmonary Disease: Associations with Spirometry and Diagnostic Utility.","authors":"Eduarda Martins de Faria, Cíntia Moraes de Sá Sousa, Caroline de Oliveira Ribeiro, Agnaldo José Lopes, Pedro Lopes de Melo","doi":"10.1007/s10439-026-04330-3","DOIUrl":"10.1007/s10439-026-04330-3","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the ability of multiscale entropy (MSE) methods to characterize alterations in airflow dynamics in chronic obstructive pulmonary disease (COPD) and to evaluate their associations with lung function and diagnostic performance.</p><p><strong>Methods: </strong>Spontaneous airflow signals were recorded during 150 s from 29 controls and 25 patients with COPD. Signal complexity was quantified using MSE, refined composite MSE (RCMSE), refined composite multiscale fuzzy entropy (RCMFE), and multiscale permutation entropy (MPE). The area under the entropy curve was calculated over predefined scale ranges (S_0-50, S_50-100, and S_0-100), and entropy at τ = 1 was also analyzed. Associations with spirometry and respiratory resistance (R6) were evaluated, and diagnostic performance was assessed using ROC analysis.</p><p><strong>Results: </strong>COPD patients showed a consistent reduction in airflow complexity across all entropy measures. Entropy indices were positively associated with spirometric parameters and inversely associated with R6, indicating progressive loss of complexity with increasing airway obstruction. The strongest correlations were observed at τ = 1, particularly with R6. Among multiscale indices, S_0-50 showed the strongest associations with lung function, suggesting predominant involvement of short-term airflow dynamics, consistent with small airway abnormalities in COPD. ROC analysis demonstrated high diagnostic accuracy for MSE and RCMSE (AUC > 0.90 for S_0-50 and SampEn₁), with comparable performance for MPE and lower accuracy for RCMFE.</p><p><strong>Conclusion: </strong>Multiscale entropy analysis of spontaneous airflow provides a sensitive, noninvasive approach for detecting and characterizing respiratory dysfunction in COPD. These methods capture clinically relevant alterations in airflow dynamics and offer complementary information to conventional lung function tests. Further studies are warranted to validate these findings and enhance their clinical applicability.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148720107","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":"Second Harmonic Generation Imaging Links Collagen Structure and Biochemical Composition in Human Osteoarthritic Cartilage.","authors":"Ziad Abusara, Eng Kuan Moo, Benafsha Tughra, Venus Joumaa, Azim Jinha, Sue Miller, Scott Timmermann, Walter Herzog","doi":"10.1007/s10439-026-04327-y","DOIUrl":"https://doi.org/10.1007/s10439-026-04327-y","url":null,"abstract":"<p><p>Articular cartilage is a highly hydrated, collagen-rich tissue that plays a critical role in joint function. Early degenerative changes in osteoarthritis (OA) are associated with alterations in collagen organization that precede gross structural damage; however, current imaging modalities, including radiography, computed tomography, and magnetic resonance imaging, often lack sufficient sensitivity to detect these microstructural changes. Second harmonic generation (SHG) imaging is a label-free optical technique sensitive to collagen microstructure. Previously, we developed an image-based parameter, the volumetric fraction of organized collagen (Φ_col), which strongly correlates with cartilage mechanical properties. In this study, we investigated whether Φ_col reflects collagen-related biochemical composition in human OA cartilage. Osteochondral samples (n = 29 blocks, 81 sections) were obtained from tibial plateaus of 11 patients undergoing total knee arthroplasty. SHG imaging was performed on superficial cryosectioned cartilage (~100-150 µm from the articular surface) to quantify Φ_col, followed by biochemical hydroxyproline assays to estimate collagen content normalized to wet tissue weight. We observed a robust positive correlation between Φ_col and hydroxyproline content (Spearman's ρ = 0.95, p < 0.05), with both measures decreasing progressively with QP-derived tissue degeneration grade. Tissue wet weight exhibited a moderate negative correlation with hydroxyproline content (ρ =  - 0.49, p < 0.05). These findings indicate that SHG-derived Φ_col is strongly associated with collagen-related structural and compositional features within the superficial cartilage layer in this standardized ex vivo imaging workflow. While the study is limited to ex vivo tissue sections from osteoarthritic joints and does not establish clinical feasibility, the results provide quantitative validation of SHG-derived metrics that may support the future development of non-destructive imaging approaches for cartilage assessment, which is currently not available.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705147","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":"Mitral Annuloplasty Sizing: Engineering Design Basis for a Scientific Clinical Approach.","authors":"Nikola Dobrilovic","doi":"10.1007/s10439-026-04221-7","DOIUrl":"https://doi.org/10.1007/s10439-026-04221-7","url":null,"abstract":"<p><strong>Introduction: </strong>For over half a century, our method of annuloplasty ring sizing for mitral (tricuspid) repair has remained unchanged. Commercially available sizers provide the surgeon estimates but no objective measurement.</p><p><strong>Methods: </strong>This manuscript defines the engineering design process for a novel, objective sizing system and illustrates its clinical application. An early cadaver animal heart model was developed to validate the sizer's ability to both manipulate and measure coaptation length.</p><p><strong>Results: </strong>An overview of the design process is presented to establish why the paired-ring sizing method is able to deliver precise mitral leaflet coaptation length measurements. The method of clinical application of a novel surgical technique is illustrated in detail. Preliminary animal heart validation results demonstrated the sizer's ability to effectively manipulate mitral annular structure and correctly predict changes in coaptation length.</p><p><strong>Conclusions: </strong>Because the paired-ring sizing technique allows coaptation length to be accurately measured and controlled, it has the potential-pending further study-to serve as the basis for a scientific annuloplasty sizing approach.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705150","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":"Inertial Microfluidic Separation of Cell Clusters from Blood Cells in Meandering Channels.","authors":"Ivan Cimrák, Michal Mulík, Monika Smiešková, Alžbeta Bugáňová, Yuhao Qiang, Franciele Flores Vit, Jianlu Zheng, Ming Dao","doi":"10.1007/s10439-026-04295-3","DOIUrl":"10.1007/s10439-026-04295-3","url":null,"abstract":"<p><strong>Purpose: </strong>Inertial microfluidics is well established for separating particles and cells by size and mechanical properties; however, its application for isolating cell clusters from single blood cells in meandering channels remains largely unexplored. This study demonstrates the potential of inertial focusing in S-shaped meandering channels to separate two-cell clusters from single cells.</p><p><strong>Methods: </strong>We first analyzed the cumulative secondary transport using passive-tracer trajectories recorded at phase-matched sections of repeated S-shaped periods. This Lagrangian analysis revealed four recurrent transport regions that help explain the observed size- and shape-dependent focusing behavior. We further developed a computational model, validated against experimental data in a nine-section meandering microchannel, which accurately predicts the distinct focusing positions of 8μm and 15μm particles-characteristic sizes of human red blood cells (RBCs) and leukocytes. The model was further validated against experiments with red blood cells and the MCF7 cell line, reproducing the observed focusing modes and transverse focusing positions.</p><p><strong>Results: </strong>Subsequently, we evaluated in silico the separation of two-cell clusters (formed by two adhered 8μm or 15μm cells, modeling circulating tumor cell clusters or leukocyte aggregates) from single blood cells across six microchannel designs of three varying widths and two heights of the channel. For different cell mixture compositions, we provide specific guidelines for optimizing channel geometry and flow velocity to achieve high-purity separation.</p><p><strong>Conclusion: </strong>This work establishes a systematic framework for designing inertial microfluidic devices to isolate cell clusters using meandering microchannels.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705124","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":"Subject-Specific Finite Element Analysis of the Foot Using a Simplified Parametric Bone Model from Weight-Bearing Radiographs.","authors":"Olamide Robiat Hassan, Siwoo Jung, Youngbin Lim, Luca Quagliato, Jungeun Gwon, Sewon Kim, Hyesu Son, Seohyun Lee, Gu-Hee Jung, Taeyong Lee","doi":"10.1007/s10439-026-04300-9","DOIUrl":"https://doi.org/10.1007/s10439-026-04300-9","url":null,"abstract":"<p><strong>Purpose: </strong>Analyzing foot biomechanics is essential for understanding plantar load distribution, particularly in relation to structural variations, including deformities such as flat foot and high arch, relative to the normal arch. Finite element analysis (FEA) is widely used to model foot biomechanics; however, traditional FEA approaches rely on detailed anatomical data from computed tomography (CT) scans, which are costly, expose subjects to radiation, and require substantial computational resources.</p><p><strong>Methods: </strong>This proof-of-concept study presents a novel pipeline for generating a simplified, parametric 3D foot bone model from weight-bearing X-ray images in four views: lateral, dorsoplantar, anteroposterior, and hindfoot alignment. Image-derived bone lengths, angles, and offsets defined geometric primitives for constructing a personalized bone assembly, which was embedded into the subject's scanned foot surface and evaluated using FEA under static standing conditions. Plantar pressure served as the primary validation metric, comparing results from the simplified model with experimental measurements and a CT-based model.</p><p><strong>Results: </strong>The simplified model reproduced the experimental plantar pressure pattern with relative errors of 4.38, 8.33, and 3.66% in the hindfoot, midfoot, and forefoot, respectively, while reducing computation time by approximately 90%. A supplementary evaluation across four additional subjects with various foot conditions showed consistent performance, with less than 9% deviation in regional peak pressure compared with experimental measurements.</p><p><strong>Conclusion: </strong>These findings demonstrate the feasibility of X-ray-based parametric modeling as a lightweight and scalable alternative for personalized foot analysis, with potential applications in rapid orthotic and insole design, subject-specific assessment in low-resource settings, and large-scale biomechanical screening.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705116","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":"Disentangling the Hemodynamic Effects of A-Wave Loss and Cardiac Output Reduction in Atrial Fibrillation.","authors":"Hailey LaBonte, Ahmad Bshennaty, Ghasaq Saleh, Salameh Al-Halaseh, Mohamad Alkhouli, Hoda Hatoum","doi":"10.1007/s10439-026-04336-x","DOIUrl":"https://doi.org/10.1007/s10439-026-04336-x","url":null,"abstract":"<p><strong>Purpose: </strong>Atrial fibrillation (AF) increases thromboembolic risk, yet the relative hemodynamic contributions of A-wave loss, cardiac output (CO) reduction, and patient-specific atrial geometry remain incompletely understood. This study aimed to isolate the hemodynamic consequences of A-wave removal and CO reduction on left atrial (LA) flow and stasis.</p><p><strong>Methods: </strong>Five patient-specific LA geometries were evaluated using transient laminar CFD simulations. For each geometry, the sinus rhythm transmitral waveform was used as the baseline and modified to represent AF with compromised and conserved CO. Hemodynamic endpoints included LA velocity, time-averaged wall shear stress (TAWSS), relative residence time (RRT), oscillatory shear index (OSI), divergence of the average wall shear stress (AWSS), and threshold-defined blood stasis metrics.</p><p><strong>Results: </strong>Analysis of the pooled spatial distributions across the 5 patient geometries showed that AF-compromised CO conditions resulted in decreased LA velocity, decreased TAWSS (0.788 to 0.508 Pa), increased RRT, and increased blood stasis regions based on velocity (61.8%), TAWSS (86.7%), and RRT (88.5%). When CO was conserved under AF conditions, peak velocity and pooled TAWSS were partially restored (0.508 to 0.827 Pa), with reductions in pooled RRT and threshold-defined stasis ratios (velocity: 42.5%; TAWSS: 59.8%; RRT: 71.7%); however, flow organization, near-wall transport patterns, and several stasis-related metrics remained altered relative to sinus rhythm despite CO restoration. Changes in AWSS indicated altered near-wall flow organization following A-wave removal.</p><p><strong>Conclusion: </strong>Waveform modifications representing AF-related alterations promoted hemodynamic conditions associated with increased flow stasis, with the magnitude of these effects depending on CO and patient anatomy. CO restoration alone did not fully normalize atrial flow organization, suggesting that A-wave loss contributes to impaired LA washout and altered near-wall hemodynamics independent of bulk flow restoration.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700481","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":"Patellofemoral Joint Contact Area During Gait is Significantly Reduced in ACL-reconstructed and Uninjured Contralateral Knees Compared to Healthy Controls.","authors":"Shanyuanye Guan, Marcus G Pandy","doi":"10.1007/s10439-026-04328-x","DOIUrl":"https://doi.org/10.1007/s10439-026-04328-x","url":null,"abstract":"<p><p>This study aimed to measure patellofemoral (PF) joint contact area for complete cycles of walking in both knees of individuals who had undergone unilateral anterior-cruciate-ligament reconstruction (ACLR) 6-15 months earlier. Computed tomography, magnetic resonance imaging, and biplane X-ray fluoroscopy were combined to determine PF contact area in the ACLR and uninjured contralateral knees of 15 individuals (26.3 ± 3.9 years) during level walking and downhill walking, and the results were compared to data for 10 healthy controls (29.8 ± 6.1 years). PF contact areas in ACLR and contralateral knees were comparable across the gait cycle for both activities, with total, lateral, and medial PF contact areas all increasing with knee flexion and reaching peak values of 560-595 mm², 399-424 mm², and 171-196 mm² respectively. Lateral contact area was consistently larger than medial contact area in ACLR, contralateral, and healthy knees. However, compared to healthy knees, PF contact areas in ACLR and contralateral knees were substantially smaller (25% - 80% lower) throughout the gait cycle in both activities. On average, total, lateral, and medial PF contact areas in ACLR and contralateral knees were approximately one-half of those in healthy knees (p < 0.001). The primary factor contributing to this reduction was a more superiorly positioned patella on the trochlea (high-riding patella), which correlated strongly with PF contact area (r = - 0.83, p < 0.001). Patellar lateral tilt also contributed to the reduction in PF contact area, showing a moderate correlation (r = - 0.44, p < 0.001). These results may be combined with calculations of PF contact force to evaluate PF joint stress in ACLR, contralateral, and healthy knees during gait.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700515","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":"Multidimensional Experimental Characterization of Lumbar Spinal Deformity.","authors":"Emma C Coltoff, Alexander Hooke, Asghar Rezaei, Philip J Brown","doi":"10.1007/s10439-026-04288-2","DOIUrl":"https://doi.org/10.1007/s10439-026-04288-2","url":null,"abstract":"<p><strong>Purpose: </strong>Spinal deformities and motions of the spinal joints are rarely confined to a single anatomical plane. Yet diagnosis of such deformities and characterizations of their biomechanical behavior under load are often limited to two-dimensional methods of analysis. This study presented a testing methodology and visualization method to characterize the biomechanical responses of the intact and deformed lumbar spine under combined loading in multiple dimensions simultaneously.</p><p><strong>Methods: </strong>Two L1-L5 lumbar spinal specimens underwent loading by five custom trajectories (rays, clockwise and counterclockwise petals and circles), each intended to perturb different responses of the spinal joints within the same range of motion.</p><p><strong>Results: </strong>Multidimensional loading highlighted differing regions of spinal stiffness between intact and deformed specimens that do not fall along the sagittal and coronal planes. The rays trajectory crucially captured the non-linear, hysteretic behavior of planar loading and unloading patterns of the spine but also suggested a potentially misleading isotropy of spinal behavior relative to the craniocaudal axis. The petals and circles trajectories appropriately capture the anisotropy of spinal bending between the sagittal and coronal planes. The clockwise and counterclockwise versions of these trajectories emphasize how deformity impacts this anisotropy in both the neutral and elastic zones.</p><p><strong>Conclusion: </strong>The insights from these trajectories highlight nuances of biomechanical behavior of the lumbar spine and disruptions due to deformity that would not be captured by pure moment loading alone. Introducing multidimensional characterization of biomechanical differences holds promise to supplement future clinical considerations for treatment of spinal deformity.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700538","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":"In Vivo Wide-Field Mapping of Microvascular Dynamics in Orthotopic GL261 Gliomas by Super-Resolution Ultrasound Imaging.","authors":"Zanhua Gao, Haoming Lin, Zhifan Yu, Huiqin Xu, Xin Chen, Xinyu Zhang, Yuanyuan Shen","doi":"10.1007/s10439-026-04333-0","DOIUrl":"https://doi.org/10.1007/s10439-026-04333-0","url":null,"abstract":"<p><strong>Purpose: </strong>The development and progression of gliomas are intimately linked to abnormal tumor angiogenesis. Different grades of gliomas exhibit distinct vascular distribution and structural characteristics. Therefore, analyzing vascular architecture and hemodynamics can provide crucial insights into tumor growth and invasion.</p><p><strong>Methods: </strong>Ultrasound localization microscopy (ULM) was applied to image the cerebrovascular changes in an orthotopic glioma mouse model at two different stages of tumor progression (14- and 21-days post-implantation). A total of twenty mice with intracranial glioma were imaged on the 14th day (n = 9) and on the 21st day (n = 11) after implantation. Pathological staining, vascular endothelial immunofluorescence examinations, and fluorescence dye perfusion were conducted to compare the ULM imaging results of the microvascular network morphology.</p><p><strong>Results: </strong>By separating slow and fast blood flow signals, the ULM images revealed distinct vascular changes that visually correlated with H&E-derived pathological features. The vascular densities in glioma regions showed a significant increase compared to the contralateral side: 30.4% on day 14 (39.91% ± 4.09% vs. 30.60% ± 3.17%, p < 0.001) and 56.5% on day 21 (42.54% ± 3.78% vs. 27.17% ± 4.56%, p < 0.001) post-glioma implantation. The vascular densities obtained from ULM images correlated strongly and significantly with pathological and vascular perfusion results (CD31 and DiI perfusion). ULM-derived multiparametric analysis further revealed significantly reduced average vessel length in glioma regions at both Day 14 (123.72 ± 28.06 μm vs. 192.90 ± 27.75 μm, p < 0.001) and Day 21 (87.07 ± 22.92 μm vs. 233.79 ± 38.94 μm, p < 0.001), decreased blood flow velocity at Day 21 (3.70 ± 0.66 mm/s vs. 4.64 ± 0.82 mm/s, p < 0.001), and increased flow-orientation heterogeneity at both Day 14 (0.838 ± 0.082 vs. 0.595 ± 0.174, p < 0.001) and Day 21 (0.812 ± 0.086 vs. 0.625 ± 0.083, p < 0.001).</p><p><strong>Conclusion: </strong>ULM imaging modality enables in vivo simultaneous structural-functional imaging of glioma microvasculature at micron-level resolution, capturing microcirculatory alterations across glioma regions. Its feasibility and reliability in visualizing vascular abnormalities were validated against ex vivo pathological and vascular perfusion, providing preclinical evidence for research and clinical applications in glioma therapy assessment and aggressiveness monitoring.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148696915","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":"From Case Studies to Cohort of Patients: Automating FSI Simulations to Uncover Downstream Effects of Ascending Aortic Grafts.","authors":"Ione Ianniruberto, Davide Astori, Simone Saitta, Davide Milesi, Pablo Villar Calle, Mario Gaudino, Leonard N Girardi, Jay D Humphrey, Jonathan W Weinsaft, Emiliano Votta, Alberto Redaelli","doi":"10.1007/s10439-026-04313-4","DOIUrl":"https://doi.org/10.1007/s10439-026-04313-4","url":null,"abstract":"<p><strong>Purpose: </strong>Open surgical repair with replacement of the diseased segment by a synthetic Dacron graft remains the standard treatment for ascending thoracic aortic aneurysms and dissections. However, post-operative sequelae, including dissection of the descending aorta (DA), have been reported and are often attributed to the mechanical compliance mismatch between the rigid graft and native aortic tissue. This mismatch can significantly alter downstream hemodynamics, potentially promoting adverse vascular remodeling and accelerating disease progression.</p><p><strong>Methods: </strong>A fully automated patient-specific fluid-structure interaction (FSI) pipeline was developed to evaluate hemodynamic changes following graft implantation based on cardiac imaging: aortic 3D anatomy is reconstructed from Magnetic Resonance Angiography; aortic wall mechanics are described as anisotropic hyperelastic, with region-specific parameters calibrated from Cine-MRI-derived wall thickness and compliance data; blood flow is modeled using inlet velocity profiles derived from 4D flow MRI and Windkessel outlet conditions tuned to in vivo pressures. The computational workflow, implemented in the open-source software SimVascular, comprised three stages: (i) computational fluid dynamics simulation to determine blood pressures, (ii) structural analysis for prestress estimation, and (iii) FSI simulation coupling fluid and solid responses. It was applied to five patients whose images were collected pre-operatively, and post-operatively. Pre-operative and post-operative scenarios were then compared to assess whether the compliance mismatch due to the presence of the ascending graft alters the hemodynamic and biomechanics in the DA.</p><p><strong>Results: </strong>The proposed framework successfully performed standardized, automated FSI simulations for all patients. Comparison between pre- and post-operative states revealed preliminary evidence of graft-associated flow remodeling, with consistent increases in flow-induced wall shear stress (WSS), oscillatory shear index, and Time Averaged WSS (TAWSS) in the aortic isthmus, which is commonly associated with post-operative dilation. Additionally, a topological analysis of WSS manifolds demonstrated a redistribution of fixed points from the ascending to the isthmus region after graft implantation, suggesting localized hemodynamic disturbances which may correlate with adverse biological responses.</p><p><strong>Conclusion: </strong>This automated framework enables large-scale patient-specific FSI analyses and highlights preliminary biomechanical changes induced by aortic grafts. The high values of WSS observed in the isthmus region suggest that next-generation compliant grafts should be designed to mitigate downstream disease progression by lowering WSSs.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148696870","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}