1
|
Hu X, Liu Q, Chen L, Cheng J, Liu M, Wu G, Sun R, Zhao G, Yang J, Ni Z. Modified Theoretical Model Predicts Radial Support Capacity of Polymer Braided Stents. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2024; 246:108063. [PMID: 38354577 DOI: 10.1016/j.cmpb.2024.108063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/22/2024] [Accepted: 02/05/2024] [Indexed: 02/16/2024]
Abstract
BACKGROUND AND OBJECTIVE Self-expanding polymer braided stents are expected to replace metallic stents in the treatment of Peripheral Arterial Disease, which seriously endangers human health. To restore the patency of blocked peripheral arteries with different properties and functions, the radial supporting capacity of the stent should be considered corresponding to the vessel. A theoretical model can be established as an effective method to study the radial supporting capacity of the stent which can shorten the stent design cycle and realize the customization of the stent according to lesion site. However, the classical model developed by Jedwab and Clerc of radial force is only limited to metallic braided stents, and the predictions for polymer braided stents are deviated. METHODS In this paper, based on the limitation of the J&C model for polymer braided stents, a modified radial force model for polymer braided stents was proposed, which considered the friction between monofilaments and the torsion of the monofilaments. And the modified model was verified by radial force tests of polymer braided stents with different structures and monofilaments. RESULTS Compared with the J&C model, the proposed modified model has better predictability for the radial force of polymer braided stents that prepared with different braided structure and polymer monofilaments. The root mean squared error of modified model is 0.041±0.026, while that of the J&C model is 0.246±0.111. CONCLUSIONS For polymer braided stents, the friction between the polymer monofilaments and the torsion of the monofilaments during the radial compression cannot be ignored. The radial force prediction accuracy of the modified model considering these factors was significantly improved. This work provides a research basis on the theoretical model of polymer braided stents, and improves the feasibility of rapid personalized customization of polymer braided stents.
Collapse
Affiliation(s)
- Xue Hu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China
| | - Qingwei Liu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China
| | - Li Chen
- Modern Education Technology Center, Henan University of Economics and Law, Zhengzhou 450046, China
| | - Jie Cheng
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China
| | - Muqing Liu
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China
| | - Gensheng Wu
- School of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Renhua Sun
- Department of Cardiology, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, Yancheng, 224006, China
| | - Gutian Zhao
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China.
| | - Juekuan Yang
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China.
| | - Zhonghua Ni
- School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, Jiangsu, China.
| |
Collapse
|
2
|
Ferretto L, Zamboni M, Vincenzi M, Bozza R, Scian S, Irsara S. Off-label use of interwoven carotid stent in common femoral artery occlusion after surgery. J Vasc Surg Cases Innov Tech 2023; 9:101214. [PMID: 37404576 PMCID: PMC10315923 DOI: 10.1016/j.jvscit.2023.101214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 04/24/2023] [Indexed: 07/06/2023] Open
Abstract
Open surgery is the gold standard for treating common and deep femoral arterial lesions. Nevertheless, significant data have emerged in recent years supporting an endovascular strategy for this peculiar anatomic region, despite certain disadvantages, including the requirement for strong compression resistance and excellent flexibility and conformability when stents are implanted. We present a case of critical limb ischemia due to total common and deep femoral arteries occlusion after endarterectomy that resulted in a very tapered lesion. It was successfully treated with percutaneous angioplasty and off-label application of an interwoven nitinol Roadsaver carotid artery stent, which demonstrated good adaptability.
Collapse
Affiliation(s)
- Luca Ferretto
- Vascular and Endovascular Surgery Section, Vascular Surgery and Angiology Unit, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| | - Matilde Zamboni
- Vascular and Endovascular Surgery Section, Vascular Surgery and Angiology Unit, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| | - Matteo Vincenzi
- Department of Radiology, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| | - Riccardo Bozza
- Vascular and Endovascular Surgery Section, Vascular Surgery and Angiology Unit, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| | - Sabrina Scian
- Vascular and Endovascular Surgery Section, Vascular Surgery and Angiology Unit, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| | - Sandro Irsara
- Vascular and Endovascular Surgery Section, Vascular Surgery and Angiology Unit, AULSS 1 Dolomiti, San Martino Hospital, Belluno, Italy
| |
Collapse
|
3
|
Bernini M, Hellmuth R, Dunlop C, Ronan W, Vaughan TJ. Recommendations for finite element modelling of nickel-titanium stents-Verification and validation activities. PLoS One 2023; 18:e0283492. [PMID: 37556457 PMCID: PMC10411813 DOI: 10.1371/journal.pone.0283492] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/11/2023] [Indexed: 08/11/2023] Open
Abstract
The objective of this study is to present a credibility assessment of finite element modelling of self-expanding nickel-titanium (Ni-Ti) stents through verification and validation (VV) activities, as set out in the ASME VV-40 standard. As part of the study, the role of calculation verification, model input sensitivity, and model validation is examined across three different application contexts (radial compression, stent deployment in a vessel, fatigue estimation). A commercially available self-expanding Ni-Ti stent was modelled, and calculation verification activities addressed the effects of mesh density, element integration and stable time increment on different quantities of interests, for each context of use considered. Sensitivity analysis of the geometrical and material input parameters and validation of deployment configuration with in vitro comparators were investigated. Results showed similar trends for global and local outputs across the contexts of use in response to the selection of discretization parameters, although with varying sensitivities. Mesh discretisation showed substantial variability for less than 4 × 4 element density across the strut cross-section in radial compression and deployment cases, while a finer grid was deemed necessary in fatigue estimation for reliable predictions of strain/stress. Element formulation also led to substantial variation depending on the chosen integration options. Furthermore, for explicit analyses, model results were highly sensitive to the chosen target time increment (e.g., mass scaling parameters), irrespective of whether quasistatic conditions were ensured (ratios of kinetic and internal energies below 5%). The higher variability was found for fatigue life simulation, with the estimation of fatigue safety factor varying up to an order of magnitude depending on the selection of discretization parameters. Model input sensitivity analysis highlighted that the predictions of outputs such as radial force and stresses showed relatively low sensitivity to Ni-Ti material parameters, which suggests that the calibration approaches used in the literature to date appear reasonable, but a higher sensitivity to stent geometry, namely strut thickness and width, was found. In contrast, the prediction of vessel diameter following deployment was least sensitive to numerical parameters, and its validation with in vitro comparators offered a simple and accurate (error ~ 1-2%) method when predicting diameter gain, and lumen area, provided that the material of the vessel is appropriately characterized and modelled.
Collapse
Affiliation(s)
- Martina Bernini
- Biomechanics Research Centre (BioMEC), College of Science and Engineering, University of Galway, Galway, Ireland
- Vascular Flow Technologies, Dundee, United Kingdom
| | | | - Craig Dunlop
- Vascular Flow Technologies, Dundee, United Kingdom
| | - William Ronan
- Biomechanics Research Centre (BioMEC), College of Science and Engineering, University of Galway, Galway, Ireland
| | - Ted J. Vaughan
- Biomechanics Research Centre (BioMEC), College of Science and Engineering, University of Galway, Galway, Ireland
| |
Collapse
|
4
|
Ubachs R, van der Sluis O, Smith S, Mertens J. Computational modeling of braided venous stents - Effect of design features and device-tissue interaction on stent performance. J Mech Behav Biomed Mater 2023; 142:105857. [PMID: 37099918 DOI: 10.1016/j.jmbbm.2023.105857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/25/2023] [Accepted: 04/12/2023] [Indexed: 04/28/2023]
Abstract
Designing venous stents with desired properties is challenging due to the partly conflicting performance criteria, e.g., enhancing flexibility may be at odds with increasing patency. To evaluate the effect of design parameters on the mechanical performance of braided stents, computational simulations are performed using finite element analysis. Model validation is performed through comparison with measurements. Considered design features are stent length, wire diameter, pick rate, number of wires, and stent end-type, being either open-ended or closed looped. Based on the requirements of venous stents, tests are defined to study the effect of design variations with respect to the following key performance criteria: chronic outward force, crush resistance, conformability, and foreshortening. Computational modeling is demonstrated to be a valuable tool in the design process through its ability of assessing sensitivities of various performance metrics to the design parameters. Additionally, it is shown, using computational modeling, that the interaction between a braided stent and its surrounding anatomy has a significant impact on its performance. Therefore, taking into account device-tissue interaction is crucial for the proper assessment of stent performance.
Collapse
Affiliation(s)
- René Ubachs
- Philips Research, High Tech Campus 34, 5656 AE Eindhoven, The Netherlands
| | - Olaf van der Sluis
- Philips Research, High Tech Campus 34, 5656 AE Eindhoven, The Netherlands; Eindhoven University of Technology, Eindhoven, The Netherlands.
| | - Scott Smith
- Philips Image Guided Therapy Devices, 5905 Nathan Lane, Plymouth, MN, United States
| | - Jake Mertens
- Philips Image Guided Therapy Devices, 5905 Nathan Lane, Plymouth, MN, United States
| |
Collapse
|
5
|
Bisighini B, Aguirre M, Biancolini ME, Trovalusci F, Perrin D, Avril S, Pierrat B. Machine learning and reduced order modelling for the simulation of braided stent deployment. Front Physiol 2023; 14:1148540. [PMID: 37064913 PMCID: PMC10090671 DOI: 10.3389/fphys.2023.1148540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/16/2023] [Indexed: 03/31/2023] Open
Abstract
Endoluminal reconstruction using flow diverters represents a novel paradigm for the minimally invasive treatment of intracranial aneurysms. The configuration assumed by these very dense braided stents once deployed within the parent vessel is not easily predictable and medical volumetric images alone may be insufficient to plan the treatment satisfactorily. Therefore, here we propose a fast and accurate machine learning and reduced order modelling framework, based on finite element simulations, to assist practitioners in the planning and interventional stages. It consists of a first classification step to determine a priori whether a simulation will be successful (good conformity between stent and vessel) or not from a clinical perspective, followed by a regression step that provides an approximated solution of the deployed stent configuration. The latter is achieved using a non-intrusive reduced order modelling scheme that combines the proper orthogonal decomposition algorithm and Gaussian process regression. The workflow was validated on an idealized intracranial artery with a saccular aneurysm and the effect of six geometrical and surgical parameters on the outcome of stent deployment was studied. We trained six machine learning models on a dataset of varying size and obtained classifiers with up to 95% accuracy in predicting the deployment outcome. The support vector machine model outperformed the others when considering a small dataset of 50 training cases, with an accuracy of 93% and a specificity of 97%. On the other hand, real-time predictions of the stent deployed configuration were achieved with an average validation error between predicted and high-fidelity results never greater than the spatial resolution of 3D rotational angiography, the imaging technique with the best spatial resolution (0.15 mm). Such accurate predictions can be reached even with a small database of 47 simulations: by increasing the training simulations to 147, the average prediction error is reduced to 0.07 mm. These results are promising as they demonstrate the ability of these techniques to achieve simulations within a few milliseconds while retaining the mechanical realism and predictability of the stent deployed configuration.
Collapse
Affiliation(s)
- Beatrice Bisighini
- Mines Saint-Étienne, University Lyon, University Jean Monnet, INSERM, Saint-Étienne, France
- Predisurge, Grande Usine Creative 2, Saint-Etienne, France
- Department of Enterprise Engineering, University Tor Vergata, Rome, Italy
| | - Miquel Aguirre
- Mines Saint-Étienne, University Lyon, University Jean Monnet, INSERM, Saint-Étienne, France
- Laboratori de Càlcul Numèric, Universitat Politècnica de Catalunya, Barcelona, Spain
- International Centre for Numerical Methods in Engineering (CIMNE), Gran Capità, Barcelona, Spain
| | | | | | - David Perrin
- Predisurge, Grande Usine Creative 2, Saint-Etienne, France
| | - Stéphane Avril
- Mines Saint-Étienne, University Lyon, University Jean Monnet, INSERM, Saint-Étienne, France
| | - Baptiste Pierrat
- Mines Saint-Étienne, University Lyon, University Jean Monnet, INSERM, Saint-Étienne, France
| |
Collapse
|
6
|
Lu YC, Hsu LI, Lin CF, Hsu CP, Chang TK, Cheng CC, Huang CH. Biomechanical characteristics of self-expanding sinus stents during crimping and deployment_A comparison between different biomaterials. J Mech Behav Biomed Mater 2023; 138:105669. [PMID: 36634436 DOI: 10.1016/j.jmbbm.2023.105669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/09/2023]
Abstract
Self-expanding sinus stents are often used in functional endoscopic sinus surgery to treat inflamed sinuses. The PROPEL self-expanding sinus stent offers mechanical support to the sinus cavity to prevent restenosis. The stent is made of a bioabsorbable material (PLGA) that disappears after wound healing. However, complications such as foreign body sensation and severe stent migration/expulsion have been reported after implantation. Little is known about the contact characteristics of self-expanding sinus stents from when the stent is crimped into the insertion device through to deployment into the sinus cavity. This current study developed a test platform to analyze the biomechanical behavior of the stent during this process. Three common bioabsorbable materials, PLGA, PCL and Mg alloy, were evaluated to understand how the choice of material affects the biomechanical characteristics of self-expanding sinus stents. The results showed that the material can have a considerable influence on the contact characteristics during crimping and deployment. When crimped, the PLGA and Mg alloy stents showed much higher plastic strain and contact stress than the PCL stent. When deployed, the PCL stent had the largest contact area (4.3 mm2) and the lowest contact pressure (0.1 MPa) on the inner surface of the sinus canal. The results indicate that PCL could be a suitable choice for self-expanding sinus stents. This current study provides a method for observing the biomechanical characteristics of sinus stents during stent crimping and deployment.
Collapse
Affiliation(s)
- Yung-Chang Lu
- Biomechanics Research Laboratory, Department of Medical Research, MacKay Memorial Hospital, Taiwan; Department of Medicine, MacKay Medical College, Taipei, Taiwan
| | - Lin-I Hsu
- Biomechanics Research Laboratory, Department of Medical Research, MacKay Memorial Hospital, Taiwan; Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chih-Feng Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Chi-Pin Hsu
- High Speed 3D Printing Research Center, National Taiwan University of Science and Technology, Taipei, Taiwan
| | - Ting-Kuo Chang
- Biomechanics Research Laboratory, Department of Medical Research, MacKay Memorial Hospital, Taiwan; Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Chung-Chih Cheng
- Medical and Pharmaceutical Industry Technology and Development Center, New Taipei City, Taiwan
| | - Chang-Hung Huang
- Biomechanics Research Laboratory, Department of Medical Research, MacKay Memorial Hospital, Taiwan; Department of Medicine, MacKay Medical College, Taipei, Taiwan; Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University, Taipei, Taiwan; School of Dentistry, National Yang Ming Chiao Tung University, Taipei, Taiwan.
| |
Collapse
|
7
|
Lucchetti A, Emonts C, Idrissi A, Gries T, Vaughan TJ. An experimental investigation of the mechanical performance of PLLA wire-braided stents. J Mech Behav Biomed Mater 2023; 138:105568. [PMID: 36459705 DOI: 10.1016/j.jmbbm.2022.105568] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 11/20/2022]
Abstract
Much of our current understanding of the performance of self-expanding wire-braided stents is based on mechanical testing of Nitinol-based or polymeric non-bioresorbable (e.g. PET, PP etc.) devices. The small amount of data present for bioresorbable devices characterizes stents with big nominal diameters (D>6mm), with a distinct lack of data describing the mechanical performance of small-diameter wire-braided bioresorbable devices (D≤5mm). This study presents a systematic investigation of the mechanical performance of wire-braided bioresorbable Poly-L-Lactic Acid (PLLA) stents having different braiding angles (α=45° , α=30°, and α=20°), wire diameters (d=100μm, and d=150μm), wire count (n=24 and n=48), braiding patterns (1:1-1, 2:2-1 and 1:1-2) and stent diameters (D=5mm, D=4mm, and D=2.5mm). Mechanical characterisation was carried out by evaluating the radial, longitudinal and bending response of the devices. Our results showed that smaller braid angles, larger wire diameters, higher number of wires and smaller stent diameter led to an increase in the stent mechanical properties across each of the three mechanical tests performed. It was found that geometrical features of a polymeric braided stent could be adapted to achieve a similar performance to the one of a metallic device. In particular, substantial increases in stent mechanical properties were found for a low braiding angle and when the braiding pattern followed a one-over-one-under configuration with two wires in parallel (1:1-2). Finally, it was shown that a mathematical model proposed in literature for metal braided stents can provide reasonable predictions also of polymeric stent performance but just in circumstances where wire friction does not have a dominant role. This study presents a wide range of experimental data that can provide an important reference for further development of wire-braided bioresorbable devices.
Collapse
Affiliation(s)
| | - Caroline Emonts
- Institut für Textiltechnik of RWTH Aachen University, Germany
| | - Akram Idrissi
- Institut für Textiltechnik of RWTH Aachen University, Germany
| | - Thomas Gries
- Institut für Textiltechnik of RWTH Aachen University, Germany
| | - Ted J Vaughan
- Biomechanics Research Centre (BioMEC), School of Engineering, College of Science and Engineering, University of Galway, Ireland.
| |
Collapse
|
8
|
Yu H, Zheng L, Qiu J, Wang J, Xu Y, Fan B, Li R, Liu J, Wang C, Fan Y. Mechanical property analysis and design parameter optimization of a novel nitinol nasal stent based on numerical simulation. Front Bioeng Biotechnol 2022; 10:1064605. [PMID: 36466347 PMCID: PMC9709141 DOI: 10.3389/fbioe.2022.1064605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 10/31/2022] [Indexed: 09/10/2023] Open
Abstract
Background: A novel braided nasal stent is an effective alternative to nasal packing after septoplasty that can be used to manage the mucosal flap after septoplasty and expand the nasal cavity. This study aimed to investigate the influence of design parameters on the mechanical properties of the nasal stent for optimal performance. Methods: A braided nasal stent modeling method was proposed and 27 stent models with a range of different geometric parameters were built. The compression behavior and bending behavior of these stent models were numerically analyzed using a finite element method (FEM). The orthogonal test was used as an optimization method, and the optimized design variables of the stent with improved performance were obtained based on range analysis and weight grade method. Results: The reaction force and bending stiffness of the braided stent increased with the wire diameter, braiding density, and external stent diameter, while wire diameter resulted as the most important determining parameter. The external stent diameter had the greatest influence on the elongation deformation. The influence of design parameters on von-Mises stress distribution of bent stent models was visualized. The stent model with geometrical parameters of 25 mm external diameter, 30° braiding angle, and 0.13 mm wire diameter (A3B3C3) had a greater reaction force but a considerably smaller bending stiffness, which was the optimal combination of parameters. Conclusion: Firstly, among the three design parameters of braided stent models, wire diameter resulted as the most important parameter determining the reaction force and bending stiffness. Secondly, the external stent diameter significantly influenced the elongation deformation during the compression simulation. Finally, 25 mm external diameter, 30° braiding angle, and 0.13 mm wire diameter (A3B3C3) was the optimal combination of stent parameters according to the orthogonal test results.
Collapse
Affiliation(s)
- Hui Yu
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Lingling Zheng
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
| | - Jikuan Qiu
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Jiayue Wang
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Yaoke Xu
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Baoshi Fan
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Rui Li
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Junxiu Liu
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, China
| | - Chao Wang
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
| | - Yubo Fan
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
| |
Collapse
|
9
|
Vallejo-Zamora JA, Vega-Cantu YI, Rodriguez C, Cordell GA, Rodriguez-Garcia A. Drug-Eluting, Bioresorbable Cardiovascular Stents─Challenges and Perspectives. ACS APPLIED BIO MATERIALS 2022; 5:4701-4717. [PMID: 36150217 DOI: 10.1021/acsabm.2c00551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Globally, the leading causes of natural death are attributed to coronary heart disease and type 1 and type 2 diabetes. High blood pressure levels, high cholesterol levels, smoking, and poor eating habits lead to the agglomeration of plaque in the arteries, reducing the blood flow. The implantation of devices used to unclog vessels, known as stents, sometimes results in a lack of irrigation due to the excessive proliferation of endothelial tissue within the blood vessels and is known as restenosis. The use of drug-eluting stents (DESs) to deliver antiproliferative drugs has led to the development of different encapsulation techniques. However, due to the potency of the drugs used in the initial stent designs, a chronic inflammatory reaction of the arterial wall known as thrombosis can cause a myocardial infarction (MI). One of the most promising drugs to reduce this risk is everolimus, which can be encapsulated in lipid systems for controlled release directly into the artery. This review aims to discuss the current status of stent design, fabrication, and functionalization. Variables such as the mechanical properties, metals and their alloys, drug encapsulation and controlled elution, and stent degradation are also addressed. Additionally, this review covers the use of polymeric surface coatings on stents and the recent advances in layer-by-layer coating and drug delivery. The advances in nanoencapsulation techniques such as liposomes and micro- and nanoemulsions and their functionalization in bioresorbable, drug-eluting stents are also highlighted.
Collapse
Affiliation(s)
- Julio A Vallejo-Zamora
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo León64849, Mexico
| | - Yadira I Vega-Cantu
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo León64849, Mexico
| | - Ciro Rodriguez
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo León64849, Mexico
- Laboratorio Nacional de Manufactura Aditiva y Digital (MADIT), Apodaca, Nuevo León66629, Mexico
| | - Geoffrey A Cordell
- Natural Products, Inc., Evanston, Illinois60201, United States
- College of Pharmacy, University of Florida, Gainesville, Florida32610, United States
| | - Aida Rodriguez-Garcia
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey, Nuevo León64849, Mexico
- Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Instituto de Biotecnología, Ciudad Universitaria, Ave. Pedro de Alba S/N, San Nicolás de los Garza, Nuevo León66455, Mexico
| |
Collapse
|
10
|
Chekotu JC, Kinahan D, Goodall R, Brabazon D. Influence of Structural Porosity and Martensite Evolution on Mechanical Characteristics of Nitinol via In-Silico Finite Element Approach. MATERIALS (BASEL, SWITZERLAND) 2022; 15:5365. [PMID: 35955298 PMCID: PMC9369952 DOI: 10.3390/ma15155365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/31/2022] [Accepted: 08/02/2022] [Indexed: 02/04/2023]
Abstract
Nitinol (NiTi) alloys are gaining extensive attention due to their excellent mechanical, superelasticity, and biocompatibility properties. It is difficult to model the complex mechanical behavior of NiTi alloys due to the solid-state diffusionless phase transformations, and the differing elasticity and plasticity presenting from these two phases. In this work, an Auricchio finite element (FE) model was used to model the mechanical behavior of superelastic NiTi and was validated with experimental data from literature. A Representative Volume Element (RVE) was used to simulate the NiTi microstructure, and a microscale study was performed to understand how the evolution of martensite phase from austenite affects the response of the material upon loading. Laser Powder Bed Fusion (L-PBF) is an effective way to build complex NiTi components. Porosity being one of the major defects in Laser Powder Bed Fusion (L-PBF) processes, the model was used to correlate the macroscale effect of porosity (1.4-83.4%) with structural stiffness, dissipated energy during phase transformations, and damping properties. The results collectively summarize the effectiveness of the Auricchio model and show that this model can aid engineers to plan NiTi processing and operational parameters, for example for heat pump, medical implant, actuator, and shock absorption applications.
Collapse
Affiliation(s)
- Josiah Cherian Chekotu
- Advanced Metallic Systems Centre for Doctoral Training, I-Form Advanced Manufacturing Research Centre, Dublin City University, D09 NR58 Dublin, Ireland
- Advanced Processing Technology Research Centre, School of Mechanical and Manufacturing Engineering, Dublin City University, D09 NR58 Dublin, Ireland
| | - David Kinahan
- Advanced Metallic Systems Centre for Doctoral Training, I-Form Advanced Manufacturing Research Centre, Dublin City University, D09 NR58 Dublin, Ireland
- Advanced Processing Technology Research Centre, School of Mechanical and Manufacturing Engineering, Dublin City University, D09 NR58 Dublin, Ireland
| | - Russell Goodall
- Advanced Metallic Systems Centre for Doctoral Training, Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK
| | - Dermot Brabazon
- Advanced Metallic Systems Centre for Doctoral Training, I-Form Advanced Manufacturing Research Centre, Dublin City University, D09 NR58 Dublin, Ireland
- Advanced Processing Technology Research Centre, School of Mechanical and Manufacturing Engineering, Dublin City University, D09 NR58 Dublin, Ireland
| |
Collapse
|
11
|
Luraghi G, Bridio S, Migliavacca F, Rodriguez Matas JF. Self-expandable stent for thrombus removal modeling: Solid or beam finite elements? Med Eng Phys 2022; 106:103836. [PMID: 35926960 DOI: 10.1016/j.medengphy.2022.103836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 06/09/2022] [Accepted: 06/13/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND The performance of self-expandable stents is being increasingly studied by means of finite-element analysis. As for peripheral stents, transcatheter valves and stent-grafts, there are numerous computational studies for setting up a proper model, this information is missing for stent-retrievers used in the procedure of thrombus removal in cerebral arteries. It is well known that the selection of the appropriate finite-element dimensions (topology) and formulations (typology) is a fundamental step to set up accurate and reliable computational simulations. In this context, a thorough verification analysis is here proposed, aimed at investigating how the different element typologies and topologies - available to model a stent-retriever - affect simulation results. METHOD Hexahedral and beam element formulations were analyzed first individually by virtually replicating a crimping test on the device, and then by replicating the thrombectomy procedure aiming at removing a thrombus from a cerebral vessel. In particular, three discretization refinements for each element type and different element formulations including both full and reduced integration were investigated and compared in terms of the resultant radial force of the stent and the stress field generated in the thrombus. RESULTS The sensitivity analysis on the element formulation performed with the crimping simulations allowed the identification of the optimal setting for each element family. Both setting lead to similar results in terms of stent performance in the virtual thrombectomy and should be used in future studies simulating the mechanical thrombectomy with stent-retrievers. CONCLUSIONS The carried out virtual thrombectomy procedures confirmed that the beam element formulation results were sufficiently accurate to model the radial force and the performance of the stent-retriever during the procedure. For different self-expandable stents, hexahedral formulation could be essential in stress analysis.
Collapse
Affiliation(s)
- Giulia Luraghi
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy.
| | - Sara Bridio
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Francesco Migliavacca
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Jose Felix Rodriguez Matas
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| |
Collapse
|
12
|
Kareem AK, Gabir MM, Ali IR, Ismail AE, Taib I, Darlis N, Almoayed OM. A review on femoropopliteal arterial deformation during daily lives and nickel-titanium stent properties. J Med Eng Technol 2022; 46:300-317. [PMID: 35234558 DOI: 10.1080/03091902.2022.2041749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The increasing number of studies on the behaviour of stent placement in recent decades provides a clear understanding of peripheral artery disease (PAD). The severe mechanical loads (axial tension and compression, bending, radial compression and torsion) deformation of the femoropopliteal artery (FPA) is responsible for the highest failure rate of permanent nickel-titanium (Nitinol) stents. Therefore, the purpose of this article is to review research papers that examined the deformation of the natural load environment of FPA, the properties of Nitinol and mechanical considerations. In conclusion, a better understanding of mechanical behaviour for FPA Nitinol stents contributes to increased mechanical performance and fatigue-life.
Collapse
Affiliation(s)
- Ali K Kareem
- Department of Biomedical Engineering, Al-Mustaqbal University College, Hillah, Iraq.,Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Batu Pahat, Malaysia
| | - Mustafa M Gabir
- Air Conditioning and Refrigeration Techniques Engineering Department, Al-Mustaqbal University College, Hillah, Iraq
| | - Inas R Ali
- Business Administration Department, Al-Mustaqbal University College, Hillah, Iraq.,Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia, Muar, Malaysia
| | - Al E Ismail
- Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Batu Pahat, Malaysia
| | - Ishkrizat Taib
- Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Batu Pahat, Malaysia
| | - Nofrizalidris Darlis
- Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Batu Pahat, Malaysia
| | - Omar M Almoayed
- Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Batu Pahat, Malaysia
| |
Collapse
|
13
|
Giuliodori A, Hernández JA, Fernandez-Sanchez D, Galve I, Soudah E. Numerical modeling of bare and polymer-covered braided stents using torsional and tensile springs connectors. J Biomech 2021; 123:110459. [PMID: 34022531 DOI: 10.1016/j.jbiomech.2021.110459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 09/30/2022]
Abstract
Computational modeling of braided stents using the finite element (FE) method has become an essential tool in the design and development of these medical devices. One of the most challenging issues in such a task is representing in an accurate manner the interaction between the interlacing wires. With the goal of achieving a compromise between accuracy and computational affordability, we propose a new approach consisting in using 1D FE formulations equipped with torsional springs at the crossover points of the wires. In the case of covered braided stents, the model is enriched with a set of tensile springs (defined in the longitudinal direction), aimed at capturing the stiffening effect of the polymeric membrane. The predictive capabilities of the proposed model are evaluated using data of our own experimental tests, as well as data from other tests in the literature. The simulations demonstrate that the proposed model is able to predict the (markedly nonlinear) behavior of stents when subjected to radial and axial cycle loads, with errors at the end of the compression stage ranging from 0.5% to 10% in all cases.
Collapse
Affiliation(s)
- Agustina Giuliodori
- Centre Internacional de Métodes Numérics en Enginerya, CIMNE, Barcelona, Spain; Universitat Politécnica de Catalunya, UPC, Barcelona, Spain.
| | - Joaquín A Hernández
- Centre Internacional de Métodes Numérics en Enginerya, CIMNE, Barcelona, Spain; E.S. d'Enginyeries Industrial, Aeroespacial i Audiovisual de Terrassa, Technical University of Catalonia, C/ Colom, 11, Terrassa 08222, Spain
| | | | | | - Eduardo Soudah
- Centre Internacional de Métodes Numérics en Enginerya, CIMNE, Barcelona, Spain; Universitat Politécnica de Catalunya, UPC, Barcelona, Spain
| |
Collapse
|
14
|
Zaccaria A, Pennati G, Petrini L. Analytical methods for braided stents design and comparison with FEA. J Mech Behav Biomed Mater 2021; 119:104560. [PMID: 33930655 DOI: 10.1016/j.jmbbm.2021.104560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 01/06/2023]
Abstract
Braiding technology is nowadays commonly adopted to build stent-like devices. Indeed, these endoprostheses, thanks to their typical great flexibility and kinking resistance, find several applications in mini-invasive treatments, involving but not limiting to the cardiovascular field. The design process usually involves many efforts and long trial and error processes before identifying the best combination of manufacturing parameters. This paper aims to provide analytical tools to support the design and optimization phases: the developed equations, based on few geometrical parameters commonly used for describing braided stents and material stiffness, are easily implementable in a worksheet and allow predicting the radial rigidity of braided stents, also involving complex features such as multiple twists and looped ends, and the diameter variation range. Finite element simulations, previously validated with respect to experimental tests, were used as a comparator to prove the reliability of the analytical results. The illustrated tools can assess the impact of each selected parameter modification and are intended to guide the optimal selection of geometrical and mechanical stent proprieties to obtain the desired radial rigidity, deliverability (minimum diameter), and, if forming processes are planned to modify the shape of the stent, the required diameter variations (maximum and minimum diameters).
Collapse
Affiliation(s)
- Alissa Zaccaria
- LaBS, Dept. of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy; Consorzio Intellimech, Bergamo, Italy.
| | - Giancarlo Pennati
- LaBS, Dept. of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy.
| | - Lorenza Petrini
- Dept. of Civil and Environmental Engineering, Politecnico di Milano, Milan, Italy.
| |
Collapse
|
15
|
McKenna CG, Vaughan TJ. A finite element investigation on design parameters of bare and polymer-covered self-expanding wire braided stents. J Mech Behav Biomed Mater 2021; 115:104305. [PMID: 33454463 DOI: 10.1016/j.jmbbm.2020.104305] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 12/02/2020] [Accepted: 12/29/2020] [Indexed: 02/07/2023]
Abstract
Self-expanding covered braided stents are routinely used across a diverse range of clinical applications, but few computational studies have attempted to replicate their complex behaviour. In this study, a computational framework was developed to predict the functional performance of bare and covered self-expanding wire braided stents, with a systematic evaluation on the effect of various braid and cover parameters presented. Simulated radial force and kink deformation tests show good agreement to experimental data for covered braided stents across a range of braid angles and cover thicknesses. Our results demonstrate that braid angle is a key governing parameter that dictates the radial and kink performance of both bare-metal and covered wire braided stents. It was also demonstrated that addition of a polymeric cover to a wire braided stent causes a stiffer radial response across all braid angles, particularly when thicker and/or stiffer covering systems were considered. This study represents the first experimentally-validated computational model for covered wire braided stent systems and has excellent potential to be used in future design of these devices for a range of applications.
Collapse
Affiliation(s)
- Ciara G McKenna
- Biomechanics Research Centre (BioMEC), Biomedical Engineering, School of Engineering, College of Science and Engineering, National University of Ireland Galway, Galway, Ireland
| | - Ted J Vaughan
- Biomechanics Research Centre (BioMEC), Biomedical Engineering, School of Engineering, College of Science and Engineering, National University of Ireland Galway, Galway, Ireland.
| |
Collapse
|
16
|
Zaccaria A, Migliavacca F, Contassot D, Heim F, Chakfe N, Pennati G, Petrini L. Finite Element Simulations of the ID Venous System to Treat Venous Compression Disorders: From Model Validation to Realistic Implant Prediction. Ann Biomed Eng 2021; 49:1493-1506. [PMID: 33398616 PMCID: PMC8137589 DOI: 10.1007/s10439-020-02694-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 11/13/2020] [Indexed: 12/17/2022]
Abstract
The ID Venous System is an innovative device proposed by ID NEST MEDICAL to treat venous compression disorders that involve bifurcations, such as the May-Thurner syndrome. The system consists of two components, ID Cav and ID Branch, combined through a specific connection that prevents the migration acting locally on the pathological region, thereby preserving the surrounding healthy tissues. Preliminary trials are required to ensure the safety and efficacy of the device, including numerical simulations. In-silico models are intended to corroborate experimental data, providing additional local information not acquirable by other means. The present work outlines the finite element model implementation and illustrates a sequential validation process, involving seven tests of increasing complexity to assess the impact of each numerical uncertainty separately. Following the standard ASME V&V40, the computational results were compared with experimental data in terms of force-displacement curves and deformed configurations, testing the model reliability for the intended context of use (differences < 10%). The deployment in a realistic geometry confirmed the feasibility of the implant procedure, without risk of rupture or plasticity of the components, highlighting the potential of the present technology.
Collapse
Affiliation(s)
- Alissa Zaccaria
- LaBS, Department of Chemistry Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy
| | - Francesco Migliavacca
- LaBS, Department of Chemistry Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy
| | | | - Frederic Heim
- Laboratoire de Physique et Mécanique Textiles (LPMT), Université de Haute-Alsace, Mulhouse, France.,Groupe Européen De Recherche Sur Les Prothèses Appliquées À La Chirurgie Vasculaire (GEPROVAS), Strasbourg, France
| | - Nabil Chakfe
- Groupe Européen De Recherche Sur Les Prothèses Appliquées À La Chirurgie Vasculaire (GEPROVAS), Strasbourg, France.,Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Giancarlo Pennati
- LaBS, Department of Chemistry Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy
| | - Lorenza Petrini
- Department of Civil and Environmental Engineering, Politecnico di Milano, Milano, Italy.
| |
Collapse
|