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Hu K, Hou Z, Huang Y, Li X, Li X, Yang L. Recent development and future application of biodegradable ureteral stents. Front Bioeng Biotechnol 2024; 12:1373130. [PMID: 38572363 PMCID: PMC10987965 DOI: 10.3389/fbioe.2024.1373130] [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: 01/19/2024] [Accepted: 03/06/2024] [Indexed: 04/05/2024] Open
Abstract
Ureteral stenting is a common clinical procedure for the treatment of upper urinary tract disorders, including conditions such as urinary tract infections, tumors, stones, and inflammation. Maintaining normal renal function by preventing and treating ureteral obstruction is the primary goal of this procedure. However, the use of ureteral stents is associated with adverse effects, including surface crusting, bacterial adhesion, and lower urinary tract symptoms (LUTS) after implantation. Recognizing the need to reduce the complications associated with permanent ureteral stent placement, there is a growing interest among both physicians and patients in the use of biodegradable ureteral stents (BUS). The evolution of stent materials and the exploration of different stent coatings have given these devices different roles tailored to different clinical needs, including anticolithic, antibacterial, antitumor, antinociceptive, and others. This review examines recent advances in BUS within the last 5 years, providing an in-depth analysis of their characteristics and performance. In addition, we present prospective insights into the future applications of BUS in clinical settings.
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Affiliation(s)
- Ke Hu
- Department of Urology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
- Research Center for Biomedical Materials, Engineering Research Center of Ministry of Education for Minimally Invasive Gastrointestinal Endoscopic Techniques, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhipeng Hou
- Research Center for Biomedical Materials, Engineering Research Center of Ministry of Education for Minimally Invasive Gastrointestinal Endoscopic Techniques, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yuanbin Huang
- Department of Urology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Xueying Li
- College of Computer Science and Engineering, Dalian Minzu University, Dalian, China
| | - Xiancheng Li
- Department of Urology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Liqun Yang
- Research Center for Biomedical Materials, Engineering Research Center of Ministry of Education for Minimally Invasive Gastrointestinal Endoscopic Techniques, Shengjing Hospital of China Medical University, Shenyang, China
- Liaoning Research Institute for Eugenic Birth and Fertility, China Medical University, Shenyang, China
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Militaru A, Bulai CA, Ene C, Popescu RI, Cozma C, Mares C, Balacescu S, Moldoveanu C, Georgescu DA, Geavlete PA, Geavlete BF. Double J Stents and Reno-Ureteral Lithiasis: Dynamic Changes in Management during the COVID-19 Pandemic. Life (Basel) 2023; 13:2113. [PMID: 38004253 PMCID: PMC10672095 DOI: 10.3390/life13112113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 10/08/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
PURPOSE To provide an evidence-based review of the use of ureteral stents in managing reno-ureteral lithiasis during the COVID-19 pandemic. MATERIALS AND METHODS A literature search was conducted between 2020 and 2023 using the PubMed and SCOPUS databases. As a part of the search query, we entered "ureteral stents" OR "double J stent" AND "renal colic" OR "ureteral obstruction" OR "reno-ureteral lithiasis" AND "COVID-19 Pandemic" OR "SARS-CoV-2 infection". RESULTS Patients with lithiasis should be categorized into low priority, intermediate priority, high priority, and emergency under the COVID-19 pandemic scenario to manage their delay and save resources, including healthcare professionals, beds, and ventilators. However, immediate interventions are necessary for individuals at risk of life-threatening septic complications. During the COVID-19 pandemic, the feasibility of conducting or resuming elective activity depended on local circumstances, the accessibility of beds and ventilators, and the execution of screening protocols. If lithiasis surgery is delayed, consequences and increased effort will be inevitable. It is possible that teleconsultation could help guide these patients and cut down on unnecessary visits and exposure. CONCLUSIONS COVID-19 has shifted treatment options for urinary stones, with ureteral stents being a safe, efficient, and cost-effective option for managing urolithiasis. Decompression is essential in emergency situations, while ureteral stents reduce the risk of infection and hospital visits.
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Affiliation(s)
- Adrian Militaru
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Catalin Andrei Bulai
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Cosmin Ene
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Razvan Ionut Popescu
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Prof. Dr. Th. Burghele” Clinical Hospital, 20 Panduri, 050659 Bucharest, Romania
| | - Cosmin Cozma
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Cristian Mares
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Stefan Balacescu
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Cristian Moldoveanu
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Dragos Adrian Georgescu
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Petrisor Aurelian Geavlete
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
| | - Bogdan Florin Geavlete
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari, 050474 Bucharest, Romania
- Department of Urology, “Saint John” Clinical Emergency Hospital, 13 Vitan-Barzesti, 042122 Bucharest, Romania
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Zong J, He Q, Liu Y, Qiu M, Wu J, Hu B. Advances in the development of biodegradable coronary stents: A translational perspective. Mater Today Bio 2022; 16:100368. [PMID: 35937578 PMCID: PMC9352968 DOI: 10.1016/j.mtbio.2022.100368] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 06/25/2022] [Accepted: 07/13/2022] [Indexed: 11/17/2022] Open
Abstract
Implantation of cardiovascular stents is an important therapeutic method to treat coronary artery diseases. Bare-metal and drug-eluting stents show promising clinical outcomes, however, their permanent presence may create complications. In recent years, numerous preclinical and clinical trials have evaluated the properties of bioresorbable stents, including polymer and magnesium-based stents. Three-dimensional (3D) printed-shape-memory polymeric materials enable the self-deployment of stents and provide a novel approach for individualized treatment. Novel bioresorbable metallic stents such as iron- and zinc-based stents have also been investigated and refined. However, the development of novel bioresorbable stents accompanied by clinical translation remains time-consuming and challenging. This review comprehensively summarizes the development of bioresorbable stents based on their preclinical/clinical trials and highlights translational research as well as novel technologies for stents (e.g., bioresorbable electronic stents integrated with biosensors). These findings are expected to inspire the design of novel stents and optimization approaches to improve the efficacy of treatments for cardiovascular diseases. Bioresorbable stents can overcome the limitations of non-degradable stents. 3D printing of shape-memory polymeric stents can lead to better clinical outcomes. Advances in Mg-, Fe- and Zn-based stents from a translational perspective. Electronic stents integrated with biosensors can covey stent status in real time. Development in the assessment of stent performance in vivo.
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Affiliation(s)
- Jiabin Zong
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Quanwei He
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Yuxiao Liu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Min Qiu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jiehong Wu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Corresponding author.
| | - Bo Hu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Corresponding author.
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Computational simulation of the flow dynamic field in a porous ureteric stent. Med Biol Eng Comput 2022; 60:2373-2387. [PMID: 35763188 PMCID: PMC9294020 DOI: 10.1007/s11517-022-02620-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 06/15/2022] [Indexed: 11/04/2022]
Abstract
Ureteric stents are employed clinically to manage urinary obstructions or other pathological conditions. Stents made of porous and biodegradable materials have gained increasing interest, because of their excellent biocompatibility and the potential for overcoming the so-called ‘forgotten stent syndrome’. However, there is very limited characterisation of their flow dynamic performance. In this study, a CFD model of the occluded and unoccluded urinary tract was developed to investigate the urinary flow dynamics in the presence of a porous ureteric stent. With increasing the permeability of the porous material (i.e., from 10−18 to 10−10 m2) both the total mass flow rate through the ureter and the average fluid velocity within the stent increased. In the unoccluded ureter, the total mass flow rate increased of 7.7% when a porous stent with permeability of 10−10 m2 was employed instead of an unporous stent. Drainage performance further improved in the presence of a ureteral occlusion, with the porous stent resulting in 10.2% greater mass flow rate compared to the unporous stent. Findings from this study provide fundamental insights into the flow performance of porous ureteric stents, with potential utility in the development pipeline of these medical devices.
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Abstract
PURPOSE OF REVIEW Ureteral stents are an invaluable tool for urologists but suffer from several drawbacks, including: limited durability due to stent encrustation, significant morbidity from bothersome urinary symptoms, pain and infection, risk of the forgotten stent and costly removal. This review highlights key advances in ureteral stent technology that seek to address these issues. RECENT FINDINGS Over the past 2 years clinical trials have brought ureteral stent technology aimed to reduce stent-associated morbidity closer to clinical application. Stent material and changes to stent design show promise in improving patient tolerability without increasing complications. Low-tech innovations such as magnetic and catheter snare removal may quickly reduce costs. Radical advances such as biodegradable stent materials remain in preclinical models but show promise for eliminating the need for stent removal. SUMMARY The ideal ureteral stent does not currently exist in clinical practice. This review highlights key studies that have advanced ureteral stent technology in the past 2 years.
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6
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Structural Modification of Polymers Functionalized with Mango Leaf Extract by Supercritical Impregnation: Approaching of Further Food and Biomedical Applications. Polymers (Basel) 2022; 14:polym14122413. [PMID: 35745986 PMCID: PMC9228015 DOI: 10.3390/polym14122413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/02/2022] [Accepted: 06/11/2022] [Indexed: 11/30/2022] Open
Abstract
Identifying new polymers from natural resources that can be effectively functionalized can have a substantial impact on biomedical devices and food preservation fields. Some of these polymers would be made of biodegradable, renewable and compostable materials, and present the kind of porosity required to effectively carry active compounds that confer on them the desired properties for their intended applications. Some natural extracts, such as mango leaf extract, have been proven to have high levels of antioxidant, antimicrobial or anti-inflammatory properties, making them good candidates for controlled-release applications. This work intends to investigate the supercritical impregnation of different types of polymers (ABS, PETG, TPU, PC and PCL) with mango leaf extract. The influence of temperature and pressure on the polymers’ structure (swelling and foaming processes) and their different behaviors have been analyzed. Thus, TPU and PC experience minimal structural modifications, while PETG, PCL and ABS, on the other hand, suffer quite significant structural changes. TPU and PETG were selected as the representative polymers for each one of these behaviors to delve into mango leaf extract impregnation processes. The bioactive capacity of the extract is present in either impregnated polymer, with 25.7% antioxidant activity by TPU processed at 35 °C and 100 bar and 32.9% antioxidant activity by PETG impregnated at 75 °C and 400 bar.
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Cui H, Zhang K, Gao C, Kang Y, Jiang H. Design and characterization of a novel braided biodegradable
double‐J
ureteral stent. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Haipo Cui
- Shanghai Institute for Minimally Invasive Therapy University of Shanghai for Science and Technology Shanghai People's Republic of China
| | - Kui Zhang
- Shanghai Institute for Minimally Invasive Therapy University of Shanghai for Science and Technology Shanghai People's Republic of China
| | - Chenguang Gao
- Shanghai Key Laboratory of Interventional Medical Devices & Equipment, and Research & Engineering Academy of MicroPort Medical Group Co., Ltd Shanghai People's Republic of China
| | - Yahong Kang
- Shanghai Key Laboratory of Interventional Medical Devices & Equipment, and Research & Engineering Academy of MicroPort Medical Group Co., Ltd Shanghai People's Republic of China
| | - Hongyan Jiang
- Shanghai Key Laboratory of Interventional Medical Devices & Equipment, and Research & Engineering Academy of MicroPort Medical Group Co., Ltd Shanghai People's Republic of China
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Urinary Stent Development and Evaluation Models: In Vitro, Ex Vivo and In Vivo-A European Network of Multidisciplinary Research to Improve Urinary Stents (ENIUS) Initiative. Polymers (Basel) 2022; 14:polym14091641. [PMID: 35566810 PMCID: PMC9102855 DOI: 10.3390/polym14091641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 04/08/2022] [Accepted: 04/17/2022] [Indexed: 12/13/2022] Open
Abstract
Background: When trying to modify urinary stents, certain pre-clinical steps have to be followed before clinical evaluation in humans. Usually, the process starts as an in silico assessment. The urinary tract is a highly complex, dynamic and variable environment, which makes a computer simulation closely reflecting physiological conditions extremely challenging. Therefore, the pre-clinical evaluation needs to go through further steps of in vitro, ex vivo and in vivo assessments. Methods and materials: Within the European Network of Multidisciplinary Research to Improve Urinary Stents (ENIUS), the authors summarized and evaluated stent assessment models in silico, in vitro, ex vivo and in vivo. The topic and relevant sub-topics were researched in a systematic literature search in Embase, Scope, Web of Science and PubMed. Clinicaltrials.gov was consulted for ongoing trials. Articles were selected systematically according to guidelines with non-relevant, non-complete, and non-English or Spanish language articles excluded. Results: In the first part of this paper, we critically evaluate in vitro stent assessment models used over the last five decades, outlining briefly their strengths and weaknesses. In the second part, we provide a step-by-step guide on what to consider when setting up an ex vivo model for stent evaluation on the example of a biodegradable stent. Lastly, the third part lists and discusses the pros and cons of available animal models for urinary stent evaluation, this being the final step before human trials. Conclusions: We hope that this overview can provide a practical guide and a critical discussion of the experimental pre-clinical evaluation steps needed, which will help interested readers in choosing the right methodology from the start of a stent evaluation process once an in silico assessment has been completed. Only a transparent multidisciplinary approach using the correct methodology will lead to a successful clinical implementation of any new or modified stent.
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Lee J, Katz M, Shah O. Developments in Ureteral Stent Technology. Front Surg 2021; 8:764167. [PMID: 34869565 PMCID: PMC8637838 DOI: 10.3389/fsurg.2021.764167] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/27/2021] [Indexed: 11/13/2022] Open
Abstract
Ureteral stents have been utilized for decades in maintaining ureteral patency, most commonly after ureteroscopy in the treatment of urolithiasis. Since their initial development, ureteral stents have had many technological advances that have allowed for better patient outcomes with improvements in comfort, durability, patency, encrustation resistance, biocompatibility, ease of insertion, migration, and biofilm development. Several new ureteral stents enter the market every year, each with their own touted benefits. It is essential to understand the different advantages for each ureteral stent to provide the best available care to patients when possible. The purpose of this review is to give a brief history of ureteral stent development and summarize the recent developments in ureteral stent designs. We aim to review the data supporting the clinical advantages of the latest ureteral stents available for use by urologists.
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Affiliation(s)
- Justin Lee
- Department of Urology, Columbia University Medical Center, New York, NY, United States
| | - Matthew Katz
- Department of Urology, Columbia University Medical Center, New York, NY, United States
| | - Ojas Shah
- Department of Urology, Columbia University Medical Center, New York, NY, United States
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Domingues B, Pacheco M, Cruz JE, Carmagnola I, Teixeira‐Santos R, Laurenti M, Can F, Bohinc K, Moutinho F, Silva JM, Aroso IM, Lima E, Reis RL, Ciardelli G, Cauda V, Mergulhão FJ, Gálvez FS, Barros AA. Future Directions for Ureteral Stent Technology: From Bench to the Market. ADVANCED THERAPEUTICS 2021. [DOI: 10.1002/adtp.202100158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Beatriz Domingues
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Margarida Pacheco
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Julia E. Cruz
- Endourology‐Endoscopy Department Minimally Invasive Surgery Centre Jesús Usón Cáceres 10071 Spain
| | - Irene Carmagnola
- Department of Mechanical and Aerospace Engineering Politecnico di Torino Turin 10129 Italy
- Polito BIOMedLAB Politecnico di Torino Turin 10129 Italy
| | - Rita Teixeira‐Santos
- LEPABE–Laboratory for Process Engineering Environment Biotechnology and Energy Faculty of Engineering University of Porto Porto 4200‐465 Portugal
| | - Marco Laurenti
- Department of Applied Science and Technology Politecnico di Torino Turin 10129 Italy
| | - Fusun Can
- Department of Medical Microbiology School of Medicine Koc University Istanbul 34450 Turkey
| | - Klemen Bohinc
- Faculty of Health Sciences University of Ljubljana Ljubljana 1000 Slovenia
| | - Fabíola Moutinho
- i3S‐Instituto de Investigação e Inovação em Saúde Universidade do Porto Porto 4200‐135 Portugal
- INEB‐Instituto de Engenharia Biomédica Universidade do Porto Porto 4200‐135 Portugal
| | - Joana M. Silva
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Ivo M. Aroso
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Estêvão Lima
- School of Health Sciences Life and Health Sciences Research Institute (ICVS) University of Minho Braga 4710‐057 Portugal
| | - Rui L. Reis
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Gianluca Ciardelli
- Department of Mechanical and Aerospace Engineering Politecnico di Torino Turin 10129 Italy
- Polito BIOMedLAB Politecnico di Torino Turin 10129 Italy
| | - Valentina Cauda
- Department of Applied Science and Technology Politecnico di Torino Turin 10129 Italy
| | - Filipe J. Mergulhão
- LEPABE–Laboratory for Process Engineering Environment Biotechnology and Energy Faculty of Engineering University of Porto Porto 4200‐465 Portugal
| | - Federico S. Gálvez
- Endourology‐Endoscopy Department Minimally Invasive Surgery Centre Jesús Usón Cáceres 10071 Spain
| | - Alexandre A. Barros
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
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Janssen P, Tailly T. New Stent Technologies. Urol Clin North Am 2021; 49:185-196. [PMID: 34776051 DOI: 10.1016/j.ucl.2021.08.004] [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: 10/20/2022]
Abstract
Ureteral stents are an indispensable part of any (endo-) urologic practice. Despite the widely demonstrated advantages of stents, they also carry a considerable risk of side effects and complications, such as urinary symptoms, pain, hematuria, decreased quality of life, stent-related infection, and encrustation. Multiple pathways in preventing or mitigating these side effects and complications and improving stent efficacy have been and are being investigated, including stent architecture and design, biomaterials, and coatings. This article provides an update on currently researched and available stents as well as future perspectives.
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Affiliation(s)
- Pieter Janssen
- Department of Urology, University Hospital Ghent, Corneel Heymanslaan 10, 9000 Ghent, Belgium
| | - Thomas Tailly
- Department of Urology, University Hospital Ghent, Corneel Heymanslaan 10, 9000 Ghent, Belgium.
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Novel method to decrease the exposure time of the extraction string of the ureteral stent and its efficiency and safety verification in the clinic. Sci Rep 2021; 11:22358. [PMID: 34785748 PMCID: PMC8595459 DOI: 10.1038/s41598-021-01821-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 11/01/2021] [Indexed: 11/08/2022] Open
Abstract
Ureteral stent removal by an extraction string is advantageous. However, the increased risk of complications attributed to the continuous exposure of the string outside the urethra must be managed. This paper introduces a method to decrease the exposure time, and conducts a retrospective study to verify its efficiency and safety. A total of 231 male patients undergoing routine ureteroscopy (URS) were included, and all of them accepted indwelling ureteral stents with strings. Among them, 123 patients (Normal-S group) underwent the normal method to determine the length of string (Lstring), which was shortened to 4 cm (cm) past the urethral meatus; 108 patients (Novel-S group) underwent the novel method (Lstring = Lurethra + 2 cm), the length of urethra (Lurethra) was measured during ureteroscopy by ureteroscope body. The demographic characteristics, stent indwelling and removal-related variables, complications, and medical costs in each group were recorded. There was no significant difference in demographic characteristics, the rate of UTI, the operative duration of URS, or the VAS pain scores for stent removal between the 2 groups. For the Novel-S group, the stent dwelling time was longer, the self-rated discomfort and symptom, the stent dislodgement rate, the numbers of clinic or emergency visits and the overall medical cost post operation was lower in comparison with the Normal-S group, while the rate of removal of stents by hand was lower, the time for removing ureteral stents was longer. This novel method improved stenting comfort, avoided ureteral stent dislodgement, decreased complications, and lowered medical costs, it was safe and reliable and merits widespread application.
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13
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Zheng S, Carugo D, Mosayyebi A, Turney B, Burkhard F, Lange D, Obrist D, Waters S, Clavica F. Fluid mechanical modeling of the upper urinary tract. WIREs Mech Dis 2021; 13:e1523. [PMID: 34730288 DOI: 10.1002/wsbm.1523] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 12/20/2022]
Abstract
The upper urinary tract (UUT) consists of kidneys and ureters, and is an integral part of the human urogenital system. Yet malfunctioning and complications of the UUT can happen at all stages of life, attributed to reasons such as congenital anomalies, urinary tract infections, urolithiasis and urothelial cancers, all of which require urological interventions and significantly compromise patients' quality of life. Therefore, many models have been developed to address the relevant scientific and clinical challenges of the UUT. Of all approaches, fluid mechanical modeling serves a pivotal role and various methods have been employed to develop physiologically meaningful models. In this article, we provide an overview on the historical evolution of fluid mechanical models of UUT that utilize theoretical, computational, and experimental approaches. Descriptions of the physiological functionality of each component are also given and the mechanical characterizations associated with the UUT are provided. As such, it is our aim to offer a brief summary of the current knowledge of the subject, and provide a comprehensive introduction for engineers, scientists, and clinicians who are interested in the field of fluid mechanical modeling of UUT. This article is categorized under: Cancer > Biomedical Engineering Infectious Diseases > Biomedical Engineering Reproductive System Diseases > Biomedical Engineering.
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Affiliation(s)
- Shaokai Zheng
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Dario Carugo
- Department of Pharmaceutics, UCL School of Pharmacy, University College London, London, UK
| | - Ali Mosayyebi
- Bioengineering Sciences, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Ben Turney
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Fiona Burkhard
- Department of Urology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Dirk Lange
- The Stone Centre at Vancouver General Hospital, Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Sarah Waters
- Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford, UK
| | - Francesco Clavica
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
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14
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Gao L, Liu X, Xu M, Sun G, Xu S, Zou T, Wang L, Wang F, Da J, Wang Y, Wang L. Biodegradable Anti-Biofilm Fiber-Membrane Ureteral Stent Constructed with a Robust Biomimetic Superhydrophilic Polycationic Hydration Surface Exhibiting Synergetic Antibacterial and Antiprotein Properties. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2006815. [PMID: 33783975 DOI: 10.1002/smll.202006815] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/01/2021] [Indexed: 06/12/2023]
Abstract
The biofouling of ureteral stents and subsequent urinary tract infections mainly come from the adsorption and adhesion of proteins and microorganisms and their ensuing proliferation. Although general polycationic surfaces in implants have good antibacterial activities, they suffer from limited durability due to severe protein and bacterial adsorption. Here, a biodegradable and anti-biofilm fiber-membrane structured ureteral stent (FMBUS) with synergetic contact-killing antibacterial activity and antiprotein adsorption is described. The stent is prepared by generating hyperbranched poly(amide-amine)-grafted polydopamine microparticles (≈300 nm) on the surface of fibers by in situ polymerization and Schiff base reactions. The biomimetic surface endows the FMBUS with a positive charge (+21.36 mV) and superhydrophilicity (water contact angle: 0°). As a result, the stents fulfilled the following functions: i) reduced attachment of host protein due to superhydrophilicity (Lysozyme: 92.1%; human serum albumin: 39.4%); ii) high bactericidal activities against contact pathogenic bacteria (contact-killing rate: 99.9999% for both E. coli and S. aureus; antiadhesion rate: 99.2% for E. coli and 99.9999% for S. aureus); iii) biocompatibility in vitro (relative growth rate of L929: >90% on day 3) and in vivo; and iv) gradient biodegradability to avoid a second surgery of stent extraction 1-2 weeks after implantation.
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Affiliation(s)
- Liheng Gao
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Xingxing Liu
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Mingxi Xu
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China
| | - Gang Sun
- Fiber and Polymer Science, University of California, Davis, CA, 95616, USA
| | - Sijun Xu
- School of Textile and Clothing, Nantong University, Nantong, 226019, China
| | - Ting Zou
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Litianmu Wang
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Fujun Wang
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Jun Da
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China
| | - Yiwei Wang
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China
| | - Lu Wang
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
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15
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Soria F, de La Cruz JE, Budia A, Cepeda M, Álvarez S, Serrano Á, Sanchez-Margallo FM. Iatrogenic Ureteral Injury Treatment with Biodegradable Antireflux Heparin-Coated Ureteral Stent-Animal Model Comparative Study. J Endourol 2021; 35:1244-1249. [PMID: 33626973 DOI: 10.1089/end.2020.0591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Objective: The aim is to assess the effectiveness of a biodegradable antireflux ureteral stent with heparin coating in a comparative study (BraidStent®-H) in an animal model for the treatment of iatrogenic ureteral perforation. Materials and Methods: A total of 24 female pigs underwent initial endoscopic, nephrosonographic, and contrast fluoroscopy assessment of the urinary tract. Afterward, unilateral iatrogenic perforation in proximal ureter model was performed. Then the animals were randomly assigned to Group-I, in which a double-pigtail stent was placed for 6 weeks, or Group-II, in which a BraidStent-H a biodegradable heparin-coated stent was placed. Follow-up assessments were performed at 1 and 6 weeks and 5 months. Results: In terms of therapeutic effectiveness, complete resolution was observed in 95.8% of Group-I animals and 87.5% in Group-II. No animals in Group-II showed vesicoureteral reflux (VUR) during the study; statistical significance was observed at 1 and 6 weeks versus Group-I. All stents in Group-II degraded without producing obstructive fragments and allowed distal ureteral peristalsis. Heparin coating was not efficient to reduce asymptomatic bacteriuria between groups. Pathologic assessment did not show any significance in the global score, but did in the "fibrosis in muscular layer" parameter, at the ureteral perforation healing area; Group-II showed higher healing quality. Conclusions: The biodegradable intraureteral BraidStent®-H is highly effective for the minimally invasive treatment of ureteral perforation, since it displays controlled and predictable degradation, avoiding the development of VUR as well as irritation of the bladder trigone. Unfortunately, heparin coating was not effective in avoiding stent-associated bacteriuria.
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Affiliation(s)
- Federico Soria
- Endoscopy-Endourology Department, Jesús Usón Minimally Invasive Surgery Centre, Cáceres, Spain
| | - Julia E de La Cruz
- Endoscopy-Endourology Department, Jesús Usón Minimally Invasive Surgery Centre, Cáceres, Spain
| | - Alberto Budia
- Urology Department, University Hospital La Fe, Valencia, Spain
| | - Marcos Cepeda
- Urology Department, University Hospital Río Hortega, Valladolid, Spain
| | - Sara Álvarez
- Urology Department, University Hospital Santiago Ramón y Cajal, Madrid, Spain
| | - Álvaro Serrano
- Urology Department, University Hospital Clínico San Carlos, Madrid, Spain
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16
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Soria F, de La Cruz JE, Fernandez T, Budia A, Serrano Á, Sanchez-Margallo FM. Heparin coating in biodegradable ureteral stents does not decrease bacterial colonization-assessment in ureteral stricture endourological treatment in animal model. Transl Androl Urol 2021; 10:1700-1710. [PMID: 33968658 PMCID: PMC8100852 DOI: 10.21037/tau-21-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background We assessed an antireflux biodegradable heparin-coated ureteral stent (BraidStent®-H) in an animal model comparative study after endoscopic treatment of ureteral strictures. Methods A total of 24 female pigs underwent initial endoscopic, nephrosonographic, and contrast fluoroscopy assessment of the urinary tract. Afterward, unilateral laparoscopic ureteral stricture model was performed. Three weeks later, the animals underwent laser endoureterotomy and were randomly assigned to Group-I, in which a double-pigtail stent was placed for 6 weeks, or Group-II, in which a BraidStent®-H was placed. Follow-up was carried out by ultrasonography, contrast fluoroscopy, ureteroscopy, urinalysis and bacteriuria assessment at 3, 6, 12 and 5 months. Finally, a pathological study of the urinary system was performed. Results There were no animals in Group-II with vesicoureteral reflux, with significance at 6 weeks with Group-I. Distal ureteral peristalsis was maintained in 50–75% in Group-II at 1–6 weeks. The 91.7% of stents in Group-II were degraded between 3–6 weeks, without obstructive fragments. Bacteriuria in Group II was 33.3–50% at 3 and 6 weeks. The global success rate by groups was 91.6% and 87.5% in groups I and II, respectively, with no statistical significance. Conclusions BraidStent®-H has been shown to be as efficacious as current ureteral stents in the treatment of benign ureteral strictures following laser endoureterotomy. In addition, it reduces the morbidity associated with current stents and has a homogeneous and predictable degradation rate of about 6 weeks, with no obstructive fragments. Future studies are required to improve the antibacterial coating to reduce BraidStent®-H contamination in view of the results obtained with the heparin coating.
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Affiliation(s)
- Federico Soria
- Endourology Department, Jesús Usón Minimally Invasive Surgery Centre Foundation, Cáceres, Spain
| | - Julia E de La Cruz
- Endourology Department, Jesús Usón Minimally Invasive Surgery Centre Foundation, Cáceres, Spain
| | - Tomás Fernandez
- Urology Department, University Hospital Morales Meseguer, Murcia, Spain
| | - Alberto Budia
- Urology Department, University Hospital La Fe, Valencia, Spain
| | - Álvaro Serrano
- Urology Department, University Hospital Clínico San Carlos, Madrid, Spain
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17
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Soria F, de la Cruz JE, Budia A, Serrano A, Galan-Llopis JA, Sanchez-Margallo FM. Experimental Assessment of New Generation of Ureteral Stents: Biodegradable and Antireflux Properties. J Endourol 2021; 34:359-365. [PMID: 31931610 DOI: 10.1089/end.2019.0493] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Objective: The aim was to assess a new biodegradable and antireflux intraureteral stent (BraidStent®) design in a swine model after ureteral laparoscopic operation. Materials and Methods: A total of 24 female pigs underwent initial endoscopic, nephrosonographic, and contrast fluoroscopy assessment of the urinary tract. Afterward, unilateral ureteropelvic junction obstruction was performed by laparoscopic approach. Six weeks later, the animals underwent laparoscopic Anderson-Hynes pyeloplasty, and were randomly assigned to Group-I, in which a double-pigtail ureteral stent was inserted for 6 weeks, or Group-II, in which a BraidStent®, a biodegradable intraureteral stent design, was placed. Follow-up assessments were performed at 3 and 6 weeks and 5 months. Results: In terms of therapeutic success, complete resolution was observed in 91.6% of Group-I animals and 88.8% in Group-II. No evidence of vesicoureteral reflux (VUR) was observed in Group-II animals and statistical significance in VUR and ureteral orifice damage were observed between groups. BraidStent® degradation occurred in a controlled manner between 3 and 6 weeks, without obstructive fragments. Distal ureteral peristalsis was maintained in 66.6% and 83.3% in Group-II at 3 and 6 weeks of follow-up, respectively. In Group-II, the positive bacteriuria rate was 41.6% and the migration rate 25%. Pathological assessment showed a significant improvement in ureteral healing in Group-II vs Group-I. Conclusions: The results of this comparative study in a porcine model indicate that the intraureteral BraidStent performed similarly to conventional ureteral stents. It avoids complete ureteral length intubation, the adverse effects associated with conventional ureteral stents, and maintains a high level of distal ureteral peristalsis. Moreover, the BraidStent® exhibited a predictable and controlled degradation rate and did not cause any obstructive fragments. However, further studies are needed to improve the anchoring system and reduce the risk of bacterial colonization.
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Affiliation(s)
- Federico Soria
- Endourology-Endoscopy Department, Minimally Invasive Surgery Centre Jesús Usón, Cáceres, Spain
| | - Julia E de la Cruz
- Endourology-Endoscopy Department, Minimally Invasive Surgery Centre Jesús Usón, Cáceres, Spain
| | - Alberto Budia
- Department of Urology, University Hospital La Fe, Valencia, Spain
| | - Alvaro Serrano
- Department of Urology, University Hospital Clínico San Carlos, Madrid, Spain
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18
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Soria F, de La Cruz JE, Caballero-Romeu JP, Pamplona M, Pérez-Fentes D, Resel-Folskerma L, Sanchez-Margallo FM. Comparative assessment of biodegradable-antireflux heparine coated ureteral stent: animal model study. BMC Urol 2021; 21:32. [PMID: 33639905 PMCID: PMC7916282 DOI: 10.1186/s12894-021-00802-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/18/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Double J ureteral stents are widely used on urological patients to provide drainage of the upper urinary tract. Unfourtunately, ureteral stents are not free from complications, as bacterial colonization and require a second procedure for removal. The purpose of the current comparative experimental study is to evaluate a new heparin-coated biodegradable antireflux ureteral stent (BraidStent®-H) to prevent urinary bacterial colonization. METHODS A total of 24 female pigs were underwent determination of bacteriuria and nephrosonographic, endoscopic and contrast fluoroscopy assessment of the urinary tract. Afterward, were randomly assigned animals to Group-I, in which a 5Fr double-pigtail ureteral stent was placed for 6 weeks, or Group-II, in which a BraidStent®-H was placed. Follow-up assessments were performed at 1, 3, 6, 8, 12 weeks. The final follow-up includes the above methods and an exhaustive pathological study of the urinary tract was accomplished after 20 weeks. RESULTS Bacteriuria findings in the first 48 h were significant between groups at 6 h and 12 h. Asymptomatic bacteriuria does not reach 100% of the animals in Group-II until 48 h versus Group-I where it appears at 6 h. The weekly bacteriuria mean rate was 27.7% and 44.4% in Group I and II respectively, without statistical significance. In Group II there were no animals with vesicoureteral reflux, with statistical significance at 3 and 6 weeks with Group-I. The 91.2% of stents in Group-II were degraded between 3 and 6 weeks, without obstructive fragments. Distal ureteral peristalsis was maintained in 66.6-75% in Group-II at 1-6 weeks. CONCLUSIONS The heparin coating of BraidStent® allows an early decrease of bacterial colonization, but its effectiveness is low at the long term. Heparin coating did not affect scheduled degradation rate or size of stents fragments. BraidStent®-H avoids the side effects associated with current ureteral stents, thus should cause less discomfort to patients.
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Affiliation(s)
- Federico Soria
- Endoscopy-Endourology Department, Jesús Usón Minimally Invasive Surgery Centre Foundation, Carretera N-521, Km. 41.8, C.P.10071, Cáceres, Spain.
| | - Julia E de La Cruz
- Endoscopy-Endourology Department, Jesús Usón Minimally Invasive Surgery Centre Foundation, Cáceres, Spain
| | - Juan Pablo Caballero-Romeu
- Urology Department, Alicante University General Hospital, Alicante Institute for Health and Biomedical Research (ISABIAL Foundation), Alicante, Spain
| | - Manuel Pamplona
- Urology Department, 12 de Octubre University Hospital, Madrid, Spain
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19
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Khoddami S, Chew BH, Lange D. Problems and solutions of stent biofilm and encrustations: A review of literature. Turk J Urol 2020; 46:S11-S18. [PMID: 33052843 DOI: 10.5152/tud.2020.20408] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022]
Abstract
A ureteral stent is a commonly implanted urological device in patients with urinary tract obstruction. The main role of these stents is to allow adequate drainage of urine from the kidney into the bladder. Individuals with strictures, tumors, or obstructions from urinary stones do not have adequate urine flow and require ureteral stents as a part of their treatment to avoid potential hydronephrosis and renal failure. Although ureteral stents are highly effective in treating urinary tract obstructions, they have associated morbidities, such as biofilm formation and encrustation. Researchers have studied about how to diminish these negative outcomes by developing novel stent materials. Different coatings and biomaterials have been developed to reduce bacterial adhesion and crystal deposition onto the stent surfaces. Moreover, new investigation technologies, such as microfluidic platforms and encrustation sensors, have been utilized to better study the stents. Biofilms and encrustations can stem from bacterial origins; therefore, understanding the urinary microbiome will also provide insight into the solutions for treating them. There are still some gaps in our knowledge regarding the exact underlying mechanisms of stent-associated biofilms and encrustation. Future studies should include continuous testing of novel stent biomaterials for safety and efficacy, developing new technologies for identifying and extracting biofilms, enriching the assessment of stent encrustation, and diving deeper into understanding the urinary microbiome.
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Affiliation(s)
- Sara Khoddami
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Ben H Chew
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Dirk Lange
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
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20
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Yeazel TR, Becker ML. Advancing Toward 3D Printing of Bioresorbable Shape Memory Polymer Stents. Biomacromolecules 2020; 21:3957-3965. [PMID: 32924443 DOI: 10.1021/acs.biomac.0c01082] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stents have evolved significantly since their introduction to the medical field in the early 1980s, becoming widely used in percutaneous coronary interventions and following nephrological procedures. However, the current commercially available stents do not degrade and remain in the body forever, leading to problems like restenosis in cardiovascular applications or requiring removal procedures in ureteral applications. Efforts to replace metal with resorbable materials have largely been halted after the commercial failure of and safety concerns elicited by Abbott's Absorb stent in 2017. Industry continues to use common polymers such as poly(l-lactide) (PLLA) and polycaprolactone (PCL) for biomedical products, but due to the weak mechanical properties of these bioresorbable materials in comparison to metals, these devices have struggled to accomplish the goals set, increasing risk of thrombosis. 3D printing stents using bioresorbable and shape memory materials could provide a method of patient-personalized production, remove the need for balloon expansion, and limit stent migration, thus bringing a new age of stent technology. The investigation of a range of 3D-printable and bioresorbable shape-memory polymers can provide solutions to the shortcomings of previously explored bioresorbable stents and revitalize the medical device industry efforts into advancing stent technology.
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Affiliation(s)
- Taylor R Yeazel
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Matthew L Becker
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.,Departments of Chemistry, Biomedical Engineering, Orthopaedic Surgery, Duke University, Durham, North Carolina 27708, United States
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21
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Gao L, Wang Y, Li Y, Xu M, Sun G, Zou T, Wang F, Xu S, Da J, Wang L. Biomimetic biodegradable Ag@Au nanoparticle-embedded ureteral stent with a constantly renewable contact-killing antimicrobial surface and antibiofilm and extraction-free properties. Acta Biomater 2020; 114:117-132. [PMID: 32683042 DOI: 10.1016/j.actbio.2020.07.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/30/2020] [Accepted: 07/13/2020] [Indexed: 12/15/2022]
Abstract
Urinary tract infections (UTIs) caused by the contamination of the ureteral stent and the pain associated with secondary stent extractions are worldwide problems in the treatment of urinary tract disorders. Here, we reported a biodegradable, long-term antibacterial, and extraction-free ureteral stent with a constantly renewable contact-killing surface and an antibiofilm function achieved by constructing a hyperbranched poly(amide-amine)-capped Ag shell and Au core nanoparticle (Ag@Au NP)-embedded fiber membrane-structured poly(glycolic acid)/poly(lactic-co-glycolic acid) (PGA/PGLA) ureteral stent. The ureteral stent showed fast contact-killing properties, i.e., 5 min for Escherichia coli and 10 min for Staphylococcus aureus, with an inhibition rate higher than 99%. In addition, gradient degradation of PGA/PGLA endowed the stent with a self-cleaning property and long-term antibacterial function by continuous exfoliation of the stent surface, thereby exposing the inner Ag@Au NPs and eliminating adherent bacteria and proteins. Subsequently, in the 16-day in vitro degradation test, the stent showed durable bactericidal activity, less total release of Ag and Au elements (6.7%, ~8 μg), and low cytotoxicity (with a relative growth rate of >80% of L929 cells). In vivo experiments on a farm pig model showed that the stent exhibited a remarkable antibiofilm property and reduced the level of inflammatory and necrotic cells. After seven days of implantation, the stent showed a gradient degradation behavior and maintained structural integrity without the presence of any large fragments in the urinary system according to the B-ultrasonic examination. The as-developed biodegradable and renewable contact-killing antibacterial strategy was efficient in preparing the ureteral stent with antibiofilm and extraction-free properties to treat stent-induced UTI. Statement of significance This study presents a customized antibiofilm solution for biodegradable implants. Two particularly important aspects of this work are as follows.
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Affiliation(s)
- Liheng Gao
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Yiwei Wang
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China
| | - Yimeng Li
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Mingxi Xu
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China
| | - Gang Sun
- Fiber and Polymer Science, University of California, Davis, CA, 95616, United States
| | - Ting Zou
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Fujun Wang
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China
| | - Sijun Xu
- School of Textile and Clothing, Nantong University, Nantong, 226019, China.
| | - Jun Da
- Department of Urology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200011, China.
| | - Lu Wang
- Key Laboratory of Textile Science and Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China.
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22
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Ramachandra M, Mosayyebi A, Carugo D, Somani BK. Strategies to Improve Patient Outcomes and QOL: Current Complications of the Design and Placements of Ureteric Stents. Res Rep Urol 2020; 12:303-314. [PMID: 32802807 PMCID: PMC7403435 DOI: 10.2147/rru.s233981] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/19/2020] [Indexed: 12/13/2022] Open
Abstract
Ureteric stents have played a vital role in relieving urinary obstruction in many urological conditions. Although they are extremely successful, stents have been associated with complications and reduced patients' health-related quality of life (HRQoL). There are many factors that may affect the quality and longevity of stents. In this review, we have highlighted the journey and innovation of ureteric stents through the modern day. A literature review was conducted to identify relevant articles over the last 20 years. There is a plethora of evidence with various indications for the use of ureteral stents and how they affect QoL. There is still ongoing research to develop the ideal stent with reduced encrustation, one that resists infection and is also comfortable for the patients. Stents made from metal alloys, polymers and biodegradable materials have unique properties in their own right but also have certain deficiencies. These have been discussed along with an overview of newly developed stents. Certain pharmacological adjuncts have also been highlighted that may be useful to improve patient's tolerance to stents. In summary, this paper describes the features of the different types of stents and the problems that are frequently encountered, including effect on patients' HRQoL and financial burden to healthcare providers.
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Affiliation(s)
- Meghana Ramachandra
- Department of Urology, University Hospital Southampton NHS Trust, Southampton, UK
| | - Ali Mosayyebi
- Mechanical Engineering Department, Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
- Institute for Life Sciences (IfLS), University of Southampton, UK
| | - Dario Carugo
- Mechanical Engineering Department, Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
- Institute for Life Sciences (IfLS), University of Southampton, UK
| | - Bhaskar K Somani
- Department of Urology, University Hospital Southampton NHS Trust, Southampton, UK
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23
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de la Cruz JE, Sanchez Margallo FM, Soria F. Response to Chow and Venkatesh re: "Experimental Assessment of New Generation of Ureteral Stents: Biodegradable and Antireflux Properties" (J Endourol 2020;34(3):366; DOI: 10.1089/end.2019.0812). J Endourol 2020; 34:367. [PMID: 32186939 DOI: 10.1089/end.2020.29076.jed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Julia E de la Cruz
- Department of Endourology-Endoscopy, Minimally Invasive Surgery Centre Jesús Usón, Cáceres, Spain
| | | | - Federico Soria
- Department of Endourology-Endoscopy, Minimally Invasive Surgery Centre Jesús Usón, Cáceres, Spain
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24
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Shan H, Cao Z, Chi C, Wang J, Wang X, Tian J, Yu B. Advances in Drug Delivery via Biodegradable Ureteral Stent for the Treatment of Upper Tract Urothelial Carcinoma. Front Pharmacol 2020; 11:224. [PMID: 32256347 PMCID: PMC7090156 DOI: 10.3389/fphar.2020.00224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 02/18/2020] [Indexed: 12/11/2022] Open
Abstract
Drug eluting ureteral stent is an effective means for local drug delivery to the urinary tract. It can potentially solve a variety of upper urinary tract problems, such as stent-related urinary tract infections and discomfort, ureteral stricture, and neoplastic diseases. However, the release of drug elutes on the surface of biostable stents is unsustainable and uncontrollable. With the development of biomaterial science, the emergence of biodegradable ureteral stents (BUSs) provides a new approach for local drug delivery in the urinary tract. The drugs can be continuously released in a controlled manner from a drug-eluting BUS, when the stent degrades. Especially for the delivery of anti-tumor drugs, the stents can obviously improve the therapeutic effectiveness of the drugs by prolonging the contact duration of the drug and tumor cells. In addition, a secondary stent removal procedure can be avoided. The purpose of this review article is to provide an overview of anti-tumor drug-eluting BUSs and discuss the biomaterials and drug delivery systems of BUS that are currently being developed to deliver anti-tumor drugs for upper tract urothelial carcinoma.
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Affiliation(s)
- Hongli Shan
- Department of Clinical Laboratory, The First Hospital of Jilin University, Changchun, China
| | - Zhongshuai Cao
- Department of Clinical Laboratory, The First Hospital of Jilin University, Changchun, China
| | - Changliang Chi
- Department of Urology, The First Hospital of Jilin University, Changchun, China
| | - Jixue Wang
- Department of Urology, The First Hospital of Jilin University, Changchun, China
| | - Xiaoqing Wang
- Department of Urology, The First Hospital of Jilin University, Changchun, China
| | - Jingyan Tian
- Department of Urology, The First Hospital of Jilin University, Changchun, China
| | - Bing Yu
- Department of Urology, The First Hospital of Jilin University, Changchun, China
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26
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Sali GM, Joshi HB. Ureteric stents: Overview of current clinical applications and economic implications. Int J Urol 2019; 27:7-15. [PMID: 31549458 DOI: 10.1111/iju.14119] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 09/01/2019] [Indexed: 12/16/2022]
Abstract
Ureteric stents are one of the most crucial tools used for various clinical conditions in the urological field. Placement of a ureteric stent, for short- or long-term use, remains one of the commonest urological interventional procedures. In the past few decades, ureteral stents have undergone notable technological advancements. However, an ideal stent without significant side-effects is yet to be engineered. Indwelling ureteric stents are often accompanied by physical distress to the patient and clinical complications, such as bacterial adhesion, encrustation, malpositioning, stent fracture and forgotten stent syndrome, that influence patients' health-related quality of life. In the market, different stent types are available, designed to reduce infections, and improve patient symptoms and tolerance. In this review, we have emphasized the recent developments that have taken place in stent design, size, materials and coating. This overview looks at current practices and problems related to stents, along with clinical and economic considerations. Few trial studies have been enumerated in the context of utilization of a ureteral stent symptom questionnaire and various stent models to compare their effects in patients.
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De Grazia A, Somani BK, Soria F, Carugo D, Mosayyebi A. Latest advancements in ureteral stent technology. Transl Androl Urol 2019; 8:S436-S441. [PMID: 31656749 DOI: 10.21037/tau.2019.08.16] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Urological diseases such as tumours, kidney stones, or strictures in the ureter can lead to a number of health consequences, including life-threatening complications. Ureteral stents have been widely used as a valid solution to restore compromised urological function. Despite their clinical success, stents are subject to failure due to encrustation and biofilm formation, potentially leading to urinary tract infection. The current review focuses on recent advancements in ureteral stent technology, which have been reported in recent scientific journals or patents. Web of Science and Google Scholar have been used as a search engine to perform this review, using the keywords "Ureteral + Stent + Design", "Ureteral + Stent + Material + Coating", "Ureteric + Stent" and "Ureteral + Stent". A significant proportion of technological developments has focused on innovating the stent design to overcome migration and urinary reflux, as well as investigating novel materials and coatings to prevent biofilm formation, such as poly(N,N-dimethylacrylamide) (PDMMA) and swellable polyethylene glycol diacrylate (PEGDA). Biodegradable ureteral stents (BUS) have also emerged as a new generation of endourological devices, overcoming the "forgotten stent syndrome" and reducing healthcare costs. Moreover, efforts have been made to develop pre-clinical test methods, both experimental and computational, which could be employed as a screening platform to inform the design of novel stent technologies.
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Affiliation(s)
- Antonio De Grazia
- Bioengineering Science Research Group, Faculty of Engineering and the Physical Sciences, University of Southampton, Southampton, UK.,Institute for Life Sciences (IfLS), University of Southampton, Southampton, UK
| | - Bhaskar K Somani
- Department of Urology, University Hospital Southampton NHS Trust, Southampton, UK
| | - Federico Soria
- Department of Endoscopy-Endourology, Minimally Invasive Surgery Centre-Jesus Usón, Cáceres, Spain
| | - Dario Carugo
- Bioengineering Science Research Group, Faculty of Engineering and the Physical Sciences, University of Southampton, Southampton, UK.,Institute for Life Sciences (IfLS), University of Southampton, Southampton, UK
| | - Ali Mosayyebi
- Bioengineering Science Research Group, Faculty of Engineering and the Physical Sciences, University of Southampton, Southampton, UK.,Institute for Life Sciences (IfLS), University of Southampton, Southampton, UK
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Zhao J, Cao Z, Lin H, Yang H, Li J, Li X, Zhang B, Yang K. In vivo research on Cu-bearing ureteral stent. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2019; 30:83. [PMID: 31273466 DOI: 10.1007/s10856-019-6285-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 06/25/2019] [Indexed: 06/09/2023]
Abstract
Infection and encrustation limit the use of ureteral stent and to data no device can completely solve these complications. The Cu-bearing stainless steel is a novel material with properties of inhibiting infection and decreasing encrustation in vitro. In this work, ureteral stents were fabricated and implanted into the bladder of New Zealand rabbits, aiming to further investigate the effects of material on bacterial survival and growth as well as the implant related encrustation. Less adherent microbes and deposited crystals on Cu-bearing stainless steel stents were found, with significant differences in comparison with stainless steel stents, which further support the development of biofunctional ureteral stents.
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Affiliation(s)
- Jing Zhao
- Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang, China
| | - Zhiqiang Cao
- General Hospital of Northern Theater Command, 110840, Shenyang, China
| | - Hao Lin
- Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang, China
| | - Hui Yang
- Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang, China
| | - Jianzhong Li
- General Hospital of Northern Theater Command, 110840, Shenyang, China
| | - Xin Li
- General Hospital of Northern Theater Command, 110840, Shenyang, China
| | - Bingchun Zhang
- Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang, China
| | - Ke Yang
- Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang, China.
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Ramstedt M, Ribeiro IAC, Bujdakova H, Mergulhão FJM, Jordao L, Thomsen P, Alm M, Burmølle M, Vladkova T, Can F, Reches M, Riool M, Barros A, Reis RL, Meaurio E, Kikhney J, Moter A, Zaat SAJ, Sjollema J. Evaluating Efficacy of Antimicrobial and Antifouling Materials for Urinary Tract Medical Devices: Challenges and Recommendations. Macromol Biosci 2019; 19:e1800384. [PMID: 30884146 DOI: 10.1002/mabi.201800384] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/18/2019] [Indexed: 01/05/2023]
Abstract
In Europe, the mean incidence of urinary tract infections in intensive care units is 1.1 per 1000 patient-days. Of these cases, catheter-associated urinary tract infections (CAUTI) account for 98%. In total, CAUTI in hospitals is estimated to give additional health-care costs of £1-2.5 billion in the United Kingdom alone. This is in sharp contrast to the low cost of urinary catheters and emphasizes the need for innovative products that reduce the incidence rate of CAUTI. Ureteral stents and other urinary-tract devices suffer similar problems. Antimicrobial strategies are being developed, however, the evaluation of their efficacy is very challenging. This review aims to provide considerations and recommendations covering all relevant aspects of antimicrobial material testing, including surface characterization, biocompatibility, cytotoxicity, in vitro and in vivo tests, microbial strain selection, and hydrodynamic conditions, all in the perspective of complying to the complex pathology of device-associated urinary tract infection. The recommendations should be on the basis of standard assays to be developed which would enable comparisons of results obtained in different research labs both in industry and in academia, as well as provide industry and academia with tools to assess the antimicrobial properties for urinary tract devices in a reliable way.
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Affiliation(s)
| | - Isabel A C Ribeiro
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-004, Lisbon, Portugal
| | - Helena Bujdakova
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 81499, Bratislava 1, Slovakia
| | - Filipe J M Mergulhão
- Laboratory for Process Engineering, Environment, Biotechnology and Energy (LEPABE), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Luisa Jordao
- Department of Environmental Health, Research and Development Unit, National Institute of Health Dr. Ricardo Jorge (INSA), Avenida Padre Cruz, 1649-016, Lisbon, Portugal
| | - Peter Thomsen
- BioModics ApS, Stengårds Alle 31A, DK-2800, Lyngby, Denmark
| | - Martin Alm
- BioModics ApS, Stengårds Alle 31A, DK-2800, Lyngby, Denmark
| | - Mette Burmølle
- Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Todorka Vladkova
- Department of Polymers, University of Chemical Technology and Metallurgy (UCTM), 8 Kliment Ohridski Blvd, 1756, Sofia, Bulgaria
| | - Fusun Can
- Department of Medical Microbiology, School of Medicine, Koc University, 34450, Sariyer, Istanbul, Turkey
| | - Meital Reches
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel
| | - Martijn Riool
- Department of Medical Microbiology, Amsterdam UMC, Amsterdam Infection and Immunity Institute, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Alexandre Barros
- 3B's Research Group, I3Bs Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Rui L Reis
- 3B's Research Group, I3Bs Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Emilio Meaurio
- Department of Mining-Metallurgy Engineering and Materials Science, POLYMAT, School of Engineering, University of the Basque Country, 48940 Leina, Bizkaia, Bilbao, Spain
| | - Judith Kikhney
- Biofilmcenter, Department of Microbiology, Infectious Diseases and Immunology, Charité University Medicine Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Annette Moter
- Biofilmcenter, Department of Microbiology, Infectious Diseases and Immunology, Charité University Medicine Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Sebastian A J Zaat
- Department of Medical Microbiology, Amsterdam UMC, Amsterdam Infection and Immunity Institute, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jelmer Sjollema
- University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
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Affiliation(s)
- Nathan Lawrentschuk
- Department of Cancer Surgery, Peter MacCallum Cancer Centre, University of Melbourne, Melbourne, Australia. .,Department of Surgery, Austin Hospital and Epworth Health, Melbourne, Australia.
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Mosayyebi A, Lange D, Yann Yue Q, Somani BK, Zhang X, Manes C, Carugo D. Reducing deposition of encrustation in ureteric stents by changing the stent architecture: A microfluidic-based investigation. BIOMICROFLUIDICS 2019; 13:014101. [PMID: 30867872 PMCID: PMC6404931 DOI: 10.1063/1.5059370] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/18/2018] [Indexed: 05/08/2023]
Abstract
Ureteric stents are clinically deployed to retain ureteral patency in the presence of an obstruction of the ureter lumen. Despite the fact that multiple stent designs have been researched in recent years, encrustation and biofilm-associated infections remain significant complications of ureteral stenting, potentially leading to the functional failure of the stent. It has been suggested that "inactive" side-holes of stents may act as anchoring sites for encrusting crystals, as they are associated with low wall shear stress (WSS) levels. Obstruction of side-holes due to encrustation is particularly detrimental to the function of the stent, since holes provide a path for urine to by-pass the occlusion. Therefore, there is an unmet need to develop novel stents to reduce deposition of encrusting particles at side-holes. In this study, we employed a stent-on-chip microfluidic model of the stented and occluded ureter to investigate the effect of stent architecture on WSS distribution and encrustation over its surface. Variations in the stent geometry encompassed (i) the wall thickness and (ii) the shape of side-holes. Stent thickness was varied in the range 0.3-0.7 mm, while streamlined side-holes of triangular shape were evaluated (with a vertex angle in the range 45°-120°). Reducing the thickness of the stent increased WSS and thus reduced the encrustation rate at side-holes. A further improvement in performance was achieved by using side-holes with a triangular shape; notably, a 45° vertex angle showed superior performance compared to other angles investigated, resulting in a significant increase in WSS within "inactive" side-holes. In conclusion, combining the optimal stent thickness (0.3 mm) and hole vertex angle (45°) resulted in a ∼90% reduction in encrustation rate within side-holes, compared to a standard design. If translated to a full-scale ureteric stent, this optimised architecture has the potential for significantly increasing the stent lifetime while reducing clinical complications.
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Affiliation(s)
| | - D. Lange
- Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver V6H 3Y8, Canada
| | - Q. Yann Yue
- Department of Mechanical Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - B. K. Somani
- Department of Urology, University Hospital Southampton NHS Trust, Southampton SO16 6YD, United Kingdom
| | | | - C. Manes
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, Turin 10129, Italy
| | - D. Carugo
- Author to whom correspondence should be addressed:
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Wang L, Yang G, Xie H, Chen F. Prospects for the research and application of biodegradable ureteral stents: from bench to bedside. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2018; 29:1657-1666. [PMID: 30141744 DOI: 10.1080/09205063.2018.1498184] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ureteral stents are commonly used in urological practices but are frequently associated with patient discomfort, encrustation and stent-related infection. And a second procedure is needed to remove the stent. New biomaterials and designs have been attempted to solve these problems. The development of biodegradable ureteral stent shows promising prospects in future clinical applications. This article reviews the biomaterials and preparation methods commonly used in the present study of biodegradable ureteral stents. To date, none of the technological developments has lead to the 'ideal' biodegradable ureteral stent, but much progress has been made in the stent design by improving the physical characteristics and biocompatibility of the biomaterials. The controllability of degradation, the biggest problem faced currently, still needs to be further improved. In the future, the nanotechnology and chemical modification of biomaterials may be able to further optimize the properties of degradation.
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Affiliation(s)
- Lin Wang
- a Department of Urology , Shanghai Children's Hospital, Shanghai Jiao Tong University , Shanghai , China
| | - Ganggang Yang
- a Department of Urology , Shanghai Children's Hospital, Shanghai Jiao Tong University , Shanghai , China
| | - Hua Xie
- a Department of Urology , Shanghai Children's Hospital, Shanghai Jiao Tong University , Shanghai , China
| | - Fang Chen
- a Department of Urology , Shanghai Children's Hospital, Shanghai Jiao Tong University , Shanghai , China
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