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PATELIS N, MORIS D, SCHIZAS D, DAMASKOS C, PERREA D, BAKOYIANNIS C, LIAKAKOS T, GEORGOPOULOS S. Animal Models in the Research of Abdominal Aortic Aneurysms Development. Physiol Res 2017; 66:899-915. [DOI: 10.33549/physiolres.933579] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is a prevalent and potentially life threatening disease. Many animal models have been developed to simulate the natural history of the disease or test preclinical endovascular devices and surgical procedures. The aim of this review is to describe different methods of AAA induction in animal models and report on the effectiveness of the methods described in inducing an analogue of a human AAA. The PubMed database was searched for publications with titles containing the following terms “animal” or ‘‘animal model(s)’’ and keywords “research”, “aneurysm(s)’’, “aorta”, “pancreatic elastase’’, “Angiotensin”, “AngII” “calcium chloride” or “CaCl2”. Starting date for this search was set to 2004, since previously bibliography was already covered by the review of Daugherty and Cassis (2004). We focused on animal studies that reported a model of aneurysm development and progression. A number of different approaches of AAA induction in animal models has been developed, used and combined since the first report in the 1960’s. Although specific methods are successful in AAA induction in animal models, it is necessary that these methods and their respective results are in line with the pathophysiology and the mechanisms involved in human AAA development. A researcher should know the advantages/disadvantages of each animal model and choose the appropriate model.
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Affiliation(s)
- N. PATELIS
- First Department of Surgery, Vascular Unit, Laikon General Hospital, Medical School, National and Kapodistrian University of Athens, Greece
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Polejaeva IA, Rutigliano HM, Wells KD. Livestock in biomedical research: history, current status and future prospective. Reprod Fertil Dev 2017; 28:112-24. [PMID: 27062879 DOI: 10.1071/rd15343] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Livestock models have contributed significantly to biomedical and surgical advances. Their contribution is particularly prominent in the areas of physiology and assisted reproductive technologies, including understanding developmental processes and disorders, from ancient to modern times. Over the past 25 years, biomedical research that traditionally embraced a diverse species approach shifted to a small number of model species (e.g. mice and rats). The initial reasons for focusing the main efforts on the mouse were the availability of murine embryonic stem cells (ESCs) and genome sequence data. This powerful combination allowed for precise manipulation of the mouse genome (knockouts, knockins, transcriptional switches etc.) leading to ground-breaking discoveries on gene functions and regulation, and their role in health and disease. Despite the enormous contribution to biomedical research, mouse models have some major limitations. Their substantial differences compared with humans in body and organ size, lifespan and inbreeding result in pronounced metabolic, physiological and behavioural differences. Comparative studies of strategically chosen domestic species can complement mouse research and yield more rigorous findings. Because genome sequence and gene manipulation tools are now available for farm animals (cattle, pigs, sheep and goats), a larger number of livestock genetically engineered (GE) models will be accessible for biomedical research. This paper discusses the use of cattle, goats, sheep and pigs in biomedical research, provides an overview of transgenic technology in farm animals and highlights some of the beneficial characteristics of large animal models of human disease compared with the mouse. In addition, status and origin of current regulation of GE biomedical models is also reviewed.
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Affiliation(s)
- Irina A Polejaeva
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, UT 84322, USA
| | - Heloisa M Rutigliano
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, UT 84322, USA
| | - Kevin D Wells
- Division of Animal Sciences, Animal Sciences Research Center, University of Missouri, Columbia, MO 65211, USA
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Animal Models Used to Explore Abdominal Aortic Aneurysms: A Systematic Review. Eur J Vasc Endovasc Surg 2016; 52:487-499. [DOI: 10.1016/j.ejvs.2016.07.004] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 07/01/2016] [Indexed: 01/09/2023]
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Joscht M, Martin M, Henin M, Nisolle JF, Kirschvink N, Dugdale A, Godart B, Coulon H, Simon V, Hontoir F, Graffin R, De Raeve Y, Vandeweerd JM. Angiographic Anatomy of External Iliac Arteries in the Sheep. Anat Histol Embryol 2015; 45:443-449. [DOI: 10.1111/ahe.12218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 10/07/2015] [Indexed: 11/28/2022]
Affiliation(s)
- M. Joscht
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - M. Martin
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - M. Henin
- Centre Hospitalier Universitaire (CHU) de Mont Godinne; Université Catholique de Louvain; Rue Dr. G. Therasse 1, 5530; Yvoir Belgium
| | - J. F. Nisolle
- Centre Hospitalier Universitaire (CHU) de Mont Godinne; Université Catholique de Louvain; Rue Dr. G. Therasse 1, 5530; Yvoir Belgium
| | - N. Kirschvink
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - A. Dugdale
- Faculty of Health and Life Sciences; University of Liverpool; Leahurst Campus CH647TE Neston UK
| | - B. Godart
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - H. Coulon
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - V. Simon
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - F. Hontoir
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - R. Graffin
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - Y. De Raeve
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
| | - J. M. Vandeweerd
- Department of Veterinary Medicine; Integrated Veterinary Research Unit - Namur Research Institute for Life Sciences (IVRU-NARILIS); University of Namur; Namur Belgium
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von Sachsen S, Senf B, Burgert O, Meixensberger J, Florek HJ, Mohr FW, Etz CD. Stent graft visualization and planning tool for endovascular surgery using finite element analysis. Int J Comput Assist Radiol Surg 2013; 9:617-33. [PMID: 24170574 DOI: 10.1007/s11548-013-0943-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 09/03/2013] [Indexed: 11/26/2022]
Abstract
PURPOSE A new approach to optimize stent graft selection for endovascular aortic repair is the use of finite element analysis. Once the finite element model is created and solved, a software module is needed to view the simulation results in the clinical work environment. A new tool for interpretation of simulation results, named Medical Postprocessor, that enables comparison of different stent graft configurations and products was designed, implemented and tested. METHODS Aortic endovascular stent graft ring forces and sealing states in the vessel landing zone of three different configurations were provided in a surgical planning software using the Medical Imaging Interaction Tool Kit (MITK) software system. For data interpretation, software modules for 2D and 3D presentations were implemented. Ten surgeons evaluated the software features of the Medical Postprocessor. These surgeons performed usability tests and answered questionnaires based on their experience with the system. RESULTS The Medical Postprocessor visualization system enabled vascular surgeons to determine the configuration with the highest overall fixation force in 16+/-6 s, best proximal sealing in 56+/-24s and highest proximal fixation force in 38+/- s. The majority considered the multiformat data provided helpful and found the Medical Postprocessor to be an efficient decision support system for stent graft selection. The evaluation of the user interface results in an ISONORM-conform user interface (113.5 points). CONCLUSION The Medical Postprocessor visualization software tool for analyzing stent graft properties was evaluated by vascular surgeons. The results show that the software can assist the interpretation of simulation results to optimize stent graft configuration and sizing.
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Affiliation(s)
- S von Sachsen
- Innovation Center Computer Assisted Surgery (ICCAS), University of Leipzig, Leipzig, Germany,
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Prasad A, Xiao N, Gong XY, Zarins CK, Figueroa CA. A computational framework for investigating the positional stability of aortic endografts. Biomech Model Mechanobiol 2013; 12:869-87. [PMID: 23143353 PMCID: PMC3638896 DOI: 10.1007/s10237-012-0450-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022]
Abstract
Endovascular aneurysm repair (Greenhalgh in N Engl J Med 362(20):1863-1871, 2010) techniques have revolutionized the treatment of thoracic and abdominal aortic aneurysm disease, greatly reducing the perioperative mortality and morbidity associated with open surgical repair techniques. However, EVAR is not free of important complications such as late device migration, endoleak formation and fracture of device components that may result in adverse events such as aneurysm enlargement, need for long-term imaging surveillance and secondary interventions or even death. These complications result from the device inability to withstand the hemodynamics of blood flow and to keep its originally intended post-operative position over time. Understanding the in vivo biomechanical working environment experienced by endografts is a critical factor in improving their long-term performance. To date, no study has investigated the mechanics of contact between device and aorta in a three-dimensional setting. In this work, we developed a comprehensive Computational Solid Mechanics and Computational Fluid Dynamics framework to investigate the mechanics of endograft positional stability. The main building blocks of this framework are: (1) Three-dimensional non-planar aortic and stent-graft geometrical models, (2) Realistic multi-material constitutive laws for aorta, stent, and graft, (3) Physiological values for blood flow and pressure, and (4) Frictional model to describe the contact between the endograft and the aorta. We introduce a new metric for numerical quantification of the positional stability of the endograft. Lastly, in the results section, we test the framework by investigating the impact of several factors that are clinically known to affect endograft stability.
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Affiliation(s)
- Anamika Prasad
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Nan Xiao
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
- Department of Biomedical Engineering, King’s College London, London SE1 7EH, UK
| | - Xiao-Yan Gong
- Medical Implant Mechanics LLC, 26895 Aliso Creek Road, Aliso Viejo, CA 92656, USA
| | | | - C. Alberto Figueroa
- Department of Biomedical Engineering, King’s College London, London SE1 7EH, UK
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Melas N, Perdikides T, Saratzis A, Saratzis N, Kiskinis D, Deaton DH. Helical EndoStaples enhance endograft fixation in an experimental model using human cadaveric aortas. J Vasc Surg 2012; 55:1726-33. [DOI: 10.1016/j.jvs.2011.11.048] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 11/02/2011] [Accepted: 11/05/2011] [Indexed: 11/27/2022]
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Corbett TJ, Molony DS, Callanan A, McGloughlin TM. The effect of vessel material properties and pulsatile wall motion on the fixation of a proximal stent of an endovascular graft. Med Eng Phys 2010; 33:106-11. [PMID: 20947409 DOI: 10.1016/j.medengphy.2010.09.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 09/21/2010] [Accepted: 09/22/2010] [Indexed: 10/18/2022]
Abstract
Migration is a serious failure mechanism associated with endovascular abdominal aortic aneurysm (AAA) repair (EVAR). The effect of vessel material properties and pulsatile wall motion on stent fixation has not been previously investigated. A proximal stent from a commercially available stent graft was implanted into the proximal neck of silicone rubber abdominal aortic aneurysm models of varying proximal neck stiffness (β=25.39 and 20.44). The stent was then dislodged by placing distal force on the stent struts. The peak force to completely dislodge the stent was measured using a loadcell. Dislodgment was performed at ambient pressure with no flow (NF) and during pulsatile flow (PF) at pressures of 120/80 mmHg and 140/100 mmHg to determine if pulsatile wall motions affected the dislodgement force. An imaging analysis was performed at ambient pressure and at pressures of 120 mmHg and 140 mmHg to investigate diameter changes on the model due to the radial force of the stent and internal pressurisation. Stent displacement forces were ~50% higher in the stiffer model (7.16-8.4 N) than in the more compliant model (3.67-4.21 N). The mean displacement force was significantly reduced by 10.95-12.83% from the case of NF to the case of PF at 120/80 mmHg. A further increase in pressure to 140/120 mmHg had no significant effect on the displacement force. The imaging analysis showed that the diameter in the region of the stent was 0.37 mm greater in the less stiff model at all the pressures which could reduce the fixation of the stent. The results suggest that the fixation of passively fixated aortic stents could be comprised in more compliant walls and that pulsatile motions of the wall can reduce the maximum stent fixation.
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Affiliation(s)
- T J Corbett
- Centre for Applied Biomedical Engineering Research (CABER), MSSi, Department of Mechanical and Aeronautical Engineering, University of Limerick, Limerick, Ireland
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Melas N, Saratzis A, Saratzis N, Lazaridis J, Psaroulis D, Trygonis K, Kiskinis D. Aortic and Iliac Fixation of Seven Endografts for Abdominal-aortic Aneurysm Repair in an Experimental Model Using Human Cadaveric Aortas. Eur J Vasc Endovasc Surg 2010; 40:429-35. [DOI: 10.1016/j.ejvs.2010.07.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Accepted: 07/03/2010] [Indexed: 10/19/2022]
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The effect of injectable biocompatible elastomer (PDMS) on the strength of the proximal fixation of endovascular aneurysm repair grafts: An in vitro study. J Vasc Surg 2010; 52:152-8. [DOI: 10.1016/j.jvs.2010.01.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/28/2009] [Accepted: 01/03/2010] [Indexed: 11/17/2022]
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Bosman WMPF, Steenhoven TJVD, Suárez DR, Hinnen JW, Valstar ER, Hamming JF. The proximal fixation strength of modern EVAR grafts in a short aneurysm neck. An in vitro study. Eur J Vasc Endovasc Surg 2009; 39:187-92. [PMID: 19939708 DOI: 10.1016/j.ejvs.2009.10.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Accepted: 10/31/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVES The study aims to measure the strength of the proximal fixation of endografts in short and long necks. DESIGN Three types of endografts were compared: Gore Excluder, Vascutek Anaconda and Medtronic Endurant. MATERIALS AND METHODS The proximal part of the stent grafts was inserted in bovine arteries and the graft was then attached to a tensile testing machine. The force to obtain dislodgement (DF) from the aorta was recorded for each graft at proximal seal lengths of 10 and 15 mm. RESULTS The median DF (interquartile range, IQR) for the Excluder, the Anaconda and the Endurant with a seal length of 15 mm was: 11.8 (10.5-12.0) N, 20.8 (18.0-30.1) N and 10.7 (10.4-11.3) N. With the shorter proximal seal of 10mm, DF was, respectively: 6.0 (4.5-6.6) N, 17.0 (11.2-36.6) N and 6.4 (6.1-12.0) N. CONCLUSIONS The proximal fixation of the Anaconda is superior to the Excluder and the Endurant at short necks of 10 and 15 mm in an experimental set-up. There is a statistically significant decrease of proximal fixation for the Excluder stent graft, when decreasing the length of the proximal neck from 15 to 10 mm.
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Affiliation(s)
- W M P F Bosman
- Department of Surgery, Section Vascular Surgery, Leiden University Medical Center, Postbox 9600, K6-R, 2300 RC Leiden, The Netherlands.
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Figueroa CA, Taylor CA, Yeh V, Chiou AJ, Zarins CK. Effect of curvature on displacement forces acting on aortic endografts: a 3-dimensional computational analysis. J Endovasc Ther 2009; 16:284-94. [PMID: 19642787 DOI: 10.1583/08-2667.1] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE To determine the effect of curvature on the magnitude and direction of displacement forces acting on aortic endografts in 3-dimensional (3D) computational models. METHOD A 3D computer model was constructed based on magnetic resonance angiography data from a patient with an infrarenal aortic aneurysm. Computational fluid dynamics tools were used to simulate realistic flow and pressure conditions of the patient. An aortic endograft was deployed in the model, and the displacement forces acting on the endograft were calculated and expressed in Newtons (N). Additional models were created to determine the effects of reducing endograft curvature, neck angulation, and iliac angulation on displacement forces. RESULTS The aortic endograft had a curved configuration as a result of the patient's anatomy, with curvature in the anterolateral direction. Total displacement force acting on the endograft was 5.0 N, with 28% of the force in a downward (caudal) direction and 72% of the force in a sideways (anterolateral) direction. Elimination of endograft curvature (planar graft configuration) reduced total displacement force to 0.8 N, with the largest component of force (70%) acting in the sideways direction. Straightening the aortic neck in the curved endograft configuration reduced the total force acting on the endograft to 4.2 N, with a reduction of the sideways component to 55% of the total force. Straightening the iliac limbs of the endograft reduced the total force acting on the endograft to 2.1 N but increased the sideways component to 91% of the total force. CONCLUSION The largest component of the force acting on the aortic endograft is in the sideways direction, with respect to the blood flow, rather than in the downward (caudal) direction as is commonly assumed. Increased curvature of the aortic endograft increases the magnitude of the sideways displacement force. The degree of angulation of the proximal and distal ends of the endograft influence the magnitude and direction of displacement force. These factors may have a significant influence on the propensity of endografts to migrate in vivo.
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Affiliation(s)
- C Alberto Figueroa
- Department of Bioengineering, Stanford University, Stanford, California, USA
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Zarins CK, Taylor CA. Endovascular device design in the future: transformation from trial and error to computational design. J Endovasc Ther 2009; 16 Suppl 1:I12-21. [PMID: 19317584 DOI: 10.1583/08-2640.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Endovascular devices have been designed by trial and error, with bench and animal testing followed by human clinical trials to determine whether the devices are safe and effective. Despite remarkable advances over the past 15 years, there are persistent concerns regarding the long-term durability of endovascular devices. This may be due to deficiencies in device design, which has lagged behind other industries in adopting computational methods that are now routinely used to design, develop, and test new aircraft and automobiles. Similar computational design and failure mode simulations that evaluate performance under stress conditions have not been widely applied in the development of endovascular devices. Advances in medical imaging and computational modeling now allow simulation of physiological conditions in patient-specific 3-dimensional vascular models, which can provide a framework to design and test the next generation of endovascular devices. This modeling will allow the prospective design of devices that can withstand the force variations in the cardiovascular system that occur during bending, coughing, and varying degrees of exercise, as well as the extremes encountered during sudden impact in contact sports. Utilization of computational design methodology that takes into consideration the physiology of the cardiovascular system will improve future endovascular devices so that they are safer and more effective and durable.
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Affiliation(s)
- Christopher K Zarins
- Stanford University School of Medicine and School of Engineering, Stanford, California, USA.
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Oshin OA, Bown MJ, McWilliams RG, Brennan JA, Vallabhaneni SR. Optimal technique for imaging iliac segments during endovascular repair of abdominal aortic aneurysms. J Endovasc Ther 2009; 16:373-9. [PMID: 19642797 DOI: 10.1583/09-2736.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE To determine if oblique angulation of the image intensifier is adequate to image the entire length of the common iliac artery during endovascular aneurysm repair or if additional caudal tilt is necessary. METHODS Using a 3D workstation, the apparent level of the iliac bifurcation (distal limit of the stent-graft) was determined on computed tomographic angiography by profiling the common iliac segment in oblique angulation only and repeated with a combination of oblique angulation and caudal tilt. Two independent observers measured twice the apparent length of the iliac segment in both profiles for 50 patients according to a set protocol. Intra- and interobserver variability was calculated using the Bland and Altman method; the differences between the two different profiles were tested using paired t tests. RESULTS Of the 50 CTA datasets reviewed, 2 datasets were excluded owing to extensive calcification of the iliac system that prevented accurate interpretation of the image. Of the 96 segments studied, the iliac segments appeared longer (better profiled) with a combination of caudal tilt and oblique angulation in 80%, with an average discrepancy of 9 mm for observer 1 (range -1 to +28) and 7 mm for observer 2 (0 to +26). The effect of caudal tilt was statistically significant for individual observers (p = 0.001 and 0.024, respectively). Forty-six percent of iliac segments measured by observer 1 and 35% by observer 2 showed that the addition of caudal tilt resulted in improved profiling by at least 10 mm. Although inter- and intraobserver variation was significant, the gain in apparent iliac length with the addition of caudal tilt was preserved. CONCLUSION When profiled with oblique angulation alone, the location of the iliac bifurcation may appear higher than its true location, resulting in underutilization of the iliac segment by >10 mm in over a third of the patients. The problem is corrected by employing additional caudal tilt.
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Affiliation(s)
- Olufemi A Oshin
- Regional Vascular Unit, Royal Liverpool University Hospital, Liverpool, UK
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Corbett TJ, Callanan A, Morris LG, Doyle BJ, Grace PA, Kavanagh EG, McGloughlin TM. A review of the in vivo and in vitro biomechanical behavior and performance of postoperative abdominal aortic aneurysms and implanted stent-grafts. J Endovasc Ther 2008; 15:468-84. [PMID: 18729555 DOI: 10.1583/08-2370.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Endovascular repair of abdominal aortic aneurysms has generated widespread interest since the procedure was first introduced two decades ago. It is frequently performed in patients who suffer from substantial comorbidities that may render them unsuitable for traditional open surgical repair. Although this minimally invasive technique substantially reduces operative risk, recovery time, and anesthesia usage in these patients, the endovascular method has been prone to a number of failure mechanisms not encountered with the open surgical method. Based on long-term results of second- and third-generation devices that are currently becoming available, this study sought to identify the most serious failure mechanisms, which may have a starting point in the morphological changes in the aneurysm and stent-graft. To investigate the "behavior" of the aneurysm after stent-graft repair, i.e., how its length, angulation, and diameter change, we utilized state-of-the-art ex vivo methods, which researchers worldwide are now using to recreate these failure modes.
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Affiliation(s)
- Timothy J Corbett
- Centre for Applied Biomedical Engineering Research, MSSI, Department of Mechanical and Aeronautical Engineering, University of Limerick, Ireland
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Scheerlinck JPY, Snibson KJ, Bowles VM, Sutton P. Biomedical applications of sheep models: from asthma to vaccines. Trends Biotechnol 2008; 26:259-66. [PMID: 18353472 DOI: 10.1016/j.tibtech.2008.02.002] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 02/04/2008] [Accepted: 02/05/2008] [Indexed: 01/27/2023]
Abstract
Although rodent models are very popular for scientific studies, it is becoming more evident that large animal models can provide unique opportunities for biomedical research. Sheep are docile in nature and large in size, which facilitates surgical manipulation, and their physiology is similar to humans. As a result, for decades they have been chosen for several models and continue to be used to study an ever-increasing array of applications. Despite this, their full potential has not been exploited. Here, we review the use of sheep as an animal model for human vaccine development, asthma pathogenesis and treatment, the study of neonatal development, and the optimization of drug delivery and surgical techniques.
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Affiliation(s)
- Jean-Pierre Y Scheerlinck
- Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Victoria, Australia
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