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Wanhainen A, Van Herzeele I, Bastos Goncalves F, Bellmunt Montoya S, Berard X, Boyle JR, D'Oria M, Prendes CF, Karkos CD, Kazimierczak A, Koelemay MJW, Kölbel T, Mani K, Melissano G, Powell JT, Trimarchi S, Tsilimparis N, Antoniou GA, Björck M, Coscas R, Dias NV, Kolh P, Lepidi S, Mees BME, Resch TA, Ricco JB, Tulamo R, Twine CP, Branzan D, Cheng SWK, Dalman RL, Dick F, Golledge J, Haulon S, van Herwaarden JA, Ilic NS, Jawien A, Mastracci TM, Oderich GS, Verzini F, Yeung KK. Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms. Eur J Vasc Endovasc Surg 2024; 67:192-331. [PMID: 38307694 DOI: 10.1016/j.ejvs.2023.11.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 02/04/2024]
Abstract
OBJECTIVE The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy. METHODS The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence. RESULTS A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed. CONCLUSION The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.
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Black SM, Maclean C, Barrientos PH, Ritos K, Kazakidi A. Reconstruction and Validation of Arterial Geometries for Computational Fluid Dynamics Using Multiple Temporal Frames of 4D Flow-MRI Magnitude Images. Cardiovasc Eng Technol 2023; 14:655-676. [PMID: 37653353 PMCID: PMC10602980 DOI: 10.1007/s13239-023-00679-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/08/2023] [Indexed: 09/02/2023]
Abstract
PURPOSE Segmentation and reconstruction of arterial blood vessels is a fundamental step in the translation of computational fluid dynamics (CFD) to the clinical practice. Four-dimensional flow magnetic resonance imaging (4D Flow-MRI) can provide detailed information of blood flow but processing this information to elucidate the underlying anatomical structures is challenging. In this study, we present a novel approach to create high-contrast anatomical images from retrospective 4D Flow-MRI data. METHODS For healthy and clinical cases, the 3D instantaneous velocities at multiple cardiac time steps were superimposed directly onto the 4D Flow-MRI magnitude images and combined into a single composite frame. This new Composite Phase-Contrast Magnetic Resonance Angiogram (CPC-MRA) resulted in enhanced and uniform contrast within the lumen. These images were subsequently segmented and reconstructed to generate 3D arterial models for CFD. Using the time-dependent, 3D incompressible Reynolds-averaged Navier-Stokes equations, the transient aortic haemodynamics was computed within a rigid wall model of patient geometries. RESULTS Validation of these models against the gold standard CT-based approach showed no statistically significant inter-modality difference regarding vessel radius or curvature (p > 0.05), and a similar Dice Similarity Coefficient and Hausdorff Distance. CFD-derived near-wall hemodynamics indicated a significant inter-modality difference (p > 0.05), though these absolute errors were small. When compared to the in vivo data, CFD-derived velocities were qualitatively similar. CONCLUSION This proof-of-concept study demonstrated that functional 4D Flow-MRI information can be utilized to retrospectively generate anatomical information for CFD models in the absence of standard imaging datasets and intravenous contrast.
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Affiliation(s)
| | - Craig Maclean
- Research and Development, Terumo Aortic, Glasgow, UK
| | - Pauline Hall Barrientos
- Clinical Physics, Queen Elizabeth University Hospital, NHS Greater Glasgow & Clyde, Glasgow, UK
| | - Konstantinos Ritos
- Department of Mechanical and Aerospace Engineering, Glasgow, UK
- Department of Mechanical Engineering, University of Thessaly, Volos, Greece
| | - Asimina Kazakidi
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK.
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Shen J, Mastrodicasa D, Tse JR, Fleischmann D. Imaging Challenges in Chronic Dissection. Semin Roentgenol 2022; 57:345-356. [PMID: 36265986 PMCID: PMC10026356 DOI: 10.1053/j.ro.2022.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 06/22/2022] [Indexed: 11/11/2022]
Abstract
Chronic aortic dissection comprises a heterogeneous group of unrepaired and repaired disease requiring lifelong clinical and imaging surveillance. CT and MRI are the main imaging modalities for longitudinal surveillance, with growing interest in emerging imaging techniques for prognostic potential. Imaging difficulties span technical and diagnostic challenges, some of which are unique to the repaired aorta, with specific complications depending on the type of repair. This review describes existing and emerging imaging techniques, outlines the technical and diagnostic challenges encountered at CT and MRI, and highlights the diagnostic pitfalls of chronic aortic dissection.
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Affiliation(s)
- Jody Shen
- Department of Radiology, Stanford University School of Medicine, Palo Alto, CA.
| | | | - Justin R Tse
- Department of Radiology, Stanford University School of Medicine, Palo Alto, CA
| | - Dominik Fleischmann
- Department of Radiology, Stanford University School of Medicine, Palo Alto, CA
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Shen J, Mastrodicasa D, Al Bulushi Y, Lin MC, Tse JR, Watkins AC, Lee JT, Fleischmann D. Thoracic Endovascular Aortic Repair for Chronic Type B Aortic Dissection: Pre- and Postprocedural Imaging. Radiographics 2022; 42:1638-1653. [PMID: 36190862 DOI: 10.1148/rg.220028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Aortic dissection is a chronic disease that requires lifelong clinical and imaging surveillance, long after the acute event. Imaging has an important role in prognosis, timing of repair, device sizing, and monitoring for complications, especially in the endovascular therapy era. Important anatomic features at preprocedural imaging include the location of the primary intimal tear and aortic zonal and branch vessel involvement, which influence the treatment strategy. Challenges of repair in the chronic phase include a small true lumen in conjunction with a stiff intimal flap, complex anatomy, and retrograde perfusion from distal reentry tears. The role of thoracic endovascular aortic repair (TEVAR) remains controversial for treatment of chronic aortic dissection. Standard TEVAR is aimed at excluding the primary intimal tear to decrease false lumen perfusion, induce false lumen thrombosis, promote aortic remodeling, and prevent aortic growth. In addition to covering the primary intimal tear with an endograft, several adjunctive techniques have been developed to mitigate retrograde false lumen perfusion. These techniques are broadly categorized into false lumen obliteration and landing zone optimization strategies, such as the provisional extension to induce complete attachment (PETTICOAT), false lumen embolization, cheese-wire fenestration, and knickerbocker techniques. Familiarity with these techniques is important to recognize expected changes and complications at postintervention imaging. The authors detail imaging options, provide examples of simple and complex endovascular repairs of aortic dissections, and highlight complications that can be associated with various techniques. Online supplemental material is available for this article. ©RSNA, 2022.
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Affiliation(s)
- Jody Shen
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Domenico Mastrodicasa
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Yarab Al Bulushi
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Margaret C Lin
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Justin R Tse
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Amelia C Watkins
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Jason T Lee
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
| | - Dominik Fleischmann
- From the Departments of Radiology (J.S., D.M., Y.A.B., M.C.L., J.R.T., D.F.); Cardiothoracic Surgery (A.C.W.), and Vascular Surgery (J.T.L.), Stanford University School of Medicine, 453 Quarry Rd, Mail Code 5659, Palo Alto, CA 94304
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Vahabli E, Mann J, Heidari BS, Lawrence‐Brown M, Norman P, Jansen S, Pardo EDJ, Doyle B. The Technological Advancement to Engineer Next-Generation Stent-Grafts: Design, Material, and Fabrication Techniques. Adv Healthc Mater 2022; 11:e2200271. [PMID: 35481675 DOI: 10.1002/adhm.202200271] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 04/04/2022] [Indexed: 12/12/2022]
Abstract
Endovascular treatment of aortic disorders has gained wide acceptance due to reduced physiological burden to the patient compared to open surgery, and ongoing stent-graft evolution has made aortic repair an option for patients with more complex anatomies. To date, commercial stent-grafts are typically developed from established production techniques with simple design structures and limited material ranges. Despite the numerous updated versions of stent-grafts by manufacturers, the reoccurrence of device-related complications raises questions about whether the current manfacturing methods are technically able to eliminate these problems. The technology trend to produce efficient medical devices, including stent-grafts and all similar implants, should eventually change direction to advanced manufacturing techniques. It is expected that through recent advancements, especially the emergence of 4D-printing and smart materials, unprecedented features can be defined for cardiovascular medical implants, like shape change and remote battery-free self-monitoring. 4D-printing technology promises adaptive functionality, a highly desirable feature enabling printed cardiovascular implants to physically transform with time to perform a programmed task. This review provides a thorough assessment of the established technologies for existing stent-grafts and provides technical commentaries on known failure modes. They then discuss the future of advanced technologies and the efforts needed to produce next-generation endovascular implants.
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Affiliation(s)
- Ebrahim Vahabli
- Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth 6009 Australia
- School of Engineering The University of Western Australia Perth 6009 Australia
| | - James Mann
- Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth 6009 Australia
- School of Engineering The University of Western Australia Perth 6009 Australia
| | - Behzad Shiroud Heidari
- Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth 6009 Australia
- School of Engineering The University of Western Australia Perth 6009 Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies University of Western Australia Perth 6009 Australia
| | | | - Paul Norman
- Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth 6009 Australia
- Medical School The University of Western Australia Perth 6009 Australia
| | - Shirley Jansen
- Curtin Medical School Curtin University Perth WA 6102 Australia
- Department of Vascular and Endovascular Surgery Sir Charles Gairdner Hospital Perth WA 6009 Australia
- Heart and Vascular Research Institute Harry Perkins Medical Research Institute Perth WA 6009 Australia
| | - Elena de Juan Pardo
- School of Engineering The University of Western Australia Perth 6009 Australia
- School of Mechanical Medical and Process Engineering Queensland University of Technology Brisbane Queensland 4059 Australia
- T3mPLATE Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth WA 6009 Australia
| | - Barry Doyle
- Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and the UWA Centre for Medical Research The University of Western Australia Perth 6009 Australia
- School of Engineering The University of Western Australia Perth 6009 Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies University of Western Australia Perth 6009 Australia
- British Heart Foundation Centre for Cardiovascular Science The University of Edinburgh Edinburgh EH16 4TJ UK
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Gulati A, Kapoor H, Donuru A, Gala K, Parekh M. Aortic Fistulas: Pathophysiologic Features, Imaging Findings, and Diagnostic Pitfalls. Radiographics 2021; 41:1335-1351. [PMID: 34328814 DOI: 10.1148/rg.2021210004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fistulas between the aorta and surrounding organs are extremely rare but can be fatal if they are not identified and treated promptly. Most of these fistulas are associated with a history of trauma or vascular intervention. However, spontaneous aortic fistulas (AoFs) can develop in patients with weakened vasculature, which can be due to advanced atherosclerotic disease, collagen-vascular disease, vasculitides, and/or hematogenous infections. The clinical features of AoFs are often nonspecific, with patients presenting with bleeding manifestations, back or abdominal pain, fever, and shock. Confirmation with invasive endoscopy is often impractical in the acute setting. Imaging plays an important role in the management of AoFs, and multiphasic multidetector CT angiography is the initial imaging examination of choice. Obvious signs of AoF include intravenous contrast material extravasation into the fistulizing hollow organ, tract visualization, and aortic graft migration into the adjacent structure. However, nonspecific indirect signs such as loss of fat planes and ectopic foci of gas are seen more commonly. These indirect signs can be confused with other entities such as infection and postoperative changes. Management may involve complex and staged surgical procedures, depending on the patient's clinical status, site of the fistula, presence of infection, and anticipated tissue friability. As endovascular interventions become more common, radiologists will need to have a high index of suspicion for this entity in patients who have a history of aneurysms, vascular repair, or trauma and present with bleeding. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ©RSNA, 2021.
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Affiliation(s)
- Aishwarya Gulati
- From the Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, Philadelphia, PA 19107 (A.G., A.D., M.P.); Department of Radiology, University of Kentucky Medical Center, Lexington, Ky (H.K.); and Division of Interventional Radiology, Tata Memorial Hospital, Homi Bhabha University, Mumbai, India (K.G.)
| | - Harit Kapoor
- From the Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, Philadelphia, PA 19107 (A.G., A.D., M.P.); Department of Radiology, University of Kentucky Medical Center, Lexington, Ky (H.K.); and Division of Interventional Radiology, Tata Memorial Hospital, Homi Bhabha University, Mumbai, India (K.G.)
| | - Achala Donuru
- From the Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, Philadelphia, PA 19107 (A.G., A.D., M.P.); Department of Radiology, University of Kentucky Medical Center, Lexington, Ky (H.K.); and Division of Interventional Radiology, Tata Memorial Hospital, Homi Bhabha University, Mumbai, India (K.G.)
| | - Kunal Gala
- From the Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, Philadelphia, PA 19107 (A.G., A.D., M.P.); Department of Radiology, University of Kentucky Medical Center, Lexington, Ky (H.K.); and Division of Interventional Radiology, Tata Memorial Hospital, Homi Bhabha University, Mumbai, India (K.G.)
| | - Maansi Parekh
- From the Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, Philadelphia, PA 19107 (A.G., A.D., M.P.); Department of Radiology, University of Kentucky Medical Center, Lexington, Ky (H.K.); and Division of Interventional Radiology, Tata Memorial Hospital, Homi Bhabha University, Mumbai, India (K.G.)
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Contemporary imaging methods for the follow-up after endovascular abdominal aneurysm repair: a review. Wideochir Inne Tech Maloinwazyjne 2019; 14:1-11. [PMID: 30766622 PMCID: PMC6372875 DOI: 10.5114/wiitm.2018.78973] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 08/21/2018] [Indexed: 11/23/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is defined as a localized enlargement of the aortic cross-section where the diameter is greater than 3 cm or more than 50% larger than the diameter in a normal segment. The most important complication of AAA is rupture, which, if untreated, results in mortality rates of up to 90%. Conventional open surgical repair is associated with significant 30-day mortality. Endovascular aneurysm repair (EVAR) is a significantly less invasive procedure; it is related to a lower early mortality rate and a lower number of perioperative complications. Although EVAR is a minimally invasive technique, lifelong follow-up imaging is necessary due to possible late complications including endoleak, recurrent aneurysm formation, graft infection, migration, kinking and thrombosis. The total rate of complications after EVAR is estimated at approximately 30%, and the rate of complications that require intervention is 2–3%. Early detection and progression analysis of such situations is crucial for proper intervention.
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Gurney-Champion OJ, Bruins Slot T, Lens E, van der Horst A, Klaassen R, van Laarhoven HWM, van Tienhoven G, van Hooft JE, Nederveen AJ, Bel A. Quantitative assessment of biliary stent artifacts on MR images: Potential implications for target delineation in radiotherapy. Med Phys 2017; 43:5603. [PMID: 27782717 DOI: 10.1118/1.4962476] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
PURPOSE Biliary stents may cause susceptibility artifacts, gradient-induced artifacts, and radio frequency (RF) induced artifacts on magnetic resonance images, which can hinder accurate target volume delineation in radiotherapy. In this study, the authors investigated and quantified the magnitude of these artifacts for stents of different materials. METHODS Eight biliary stents made of nitinol, platinum-cored nitinol, stainless steel, or polyethylene from seven vendors, with different lengths (57-98 mm) and diameters (3.0-11.7 mm), were placed in a phantom. To quantify the susceptibility artifacts sequence-independently, ΔB0-maps and T2∗-maps were acquired at 1.5 and 3 T. To study the effect of the gradient-induced artifacts at 3 T, signal decay in images obtained with maximum readout gradient-induced artifacts was compared to signal decay in reference scans. To quantify the RF induced artifacts at 3 T, B1-maps were acquired. Finally, ΔB0-maps and T2∗-maps were acquired at 3 T of two pancreatic cancer patients who had received platinum-cored nitinol biliary stents. RESULTS Outside the stent, susceptibility artifacts dominated the other artifacts. The stainless steel stent produced the largest susceptibility artifacts. The other stents caused decreased T2∗ up to 5.1 mm (1.5 T) and 8.5 mm (3 T) from the edge of the stent. For sequences with a higher bandwidth per voxel (1.5 T: BWvox > 275 Hz/voxel; 3 T: BWvox > 500 Hz/voxel), the B0-related susceptibility artifacts were negligible (<0.2 voxels). The polyethylene stent showed no artifacts. In vivo, the changes in B0 and T2∗ induced by the stent were larger than typical variations in B0 and T2∗ induced by anatomy when the stent was at an angle of 30° with the main magnetic field. CONCLUSIONS Susceptibility artifacts were dominating over the other artifacts. The magnitudes of the susceptibility artifacts were determined sequence-independently. This method allows to include additional safety margins that ensure target irradiation.
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Affiliation(s)
- Oliver J Gurney-Champion
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands and Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Thijs Bruins Slot
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Remy Klaassen
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands and Laboratory for Experimental Oncology and Radiobiology, Center for Experimental Molecular Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Hanneke W M van Laarhoven
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Jeanin E van Hooft
- Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Aart J Nederveen
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
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den Harder AM, Suchá D, van Hamersvelt RW, Budde RPJ, de Jong PA, Schilham AMR, Bos C, Breur JMPJ, Leiner T. Imaging of pediatric great vessel stents: Computed tomography or magnetic resonance imaging? PLoS One 2017; 12:e0171138. [PMID: 28141852 PMCID: PMC5283725 DOI: 10.1371/journal.pone.0171138] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/16/2017] [Indexed: 11/28/2022] Open
Abstract
Background Complications might occur after great vessel stent implantation in children. Therefore follow-up using imaging is warranted. Purpose To determine the optimal imaging modality for the assessment of stents used to treat great vessel obstructions in children. Material and methods Five different large vessel stents were evaluated in an in-vitro setting. All stents were expanded to the maximal vendor recommended diameter (20mm; n = 4 or 10mm; n = 1), placed in an anthropomorphic chest phantom and imaged with a 256-slice CT-scanner. MRI images were acquired at 1.5T using a multi-slice T2-weighted turbo spin echo, an RF-spoiled three-dimensional T1-weighted Fast Field Echo and a balanced turbo field echo 3D sequence. Two blinded observers assessed stent lumen visibility (measured diameter/true diameter *100%) in the center and at the outlets of the stent. Reproducibility of diameter measurements was evaluated using the intraclass correlation coefficient for reliability and 95% limits of agreement for agreement analysis. Results Median stent lumen visibility was 88 (IQR 86–90)% with CT for all stents at both the center and outlets. With MRI, the T2-weighted turbo spin echo sequence was preferred which resulted in 82 (78–84%) stent lumen visibility. Interobserver reliability and agreement was good for both CT (ICC 0.997, mean difference -0.51 [-1.07–0.05] mm) and MRI measurements (ICC 0.951, mean difference -0.05 [-2.52 –-2.41] mm). Conclusion Good in-stent lumen visibility was achievable in this in-vitro study with both CT and MRI in different great vessel stents. Overall reliability was good with clinical acceptable limits of agreement for both CT and MRI. However, common conditions such as in-stent stenosis and associated aneurysms were not tested in this in-vitro study, limiting the value of the in-vitro study.
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Affiliation(s)
- A. M. den Harder
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
- * E-mail:
| | - D. Suchá
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - R. W. van Hamersvelt
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - R. P. J. Budde
- Department of Radiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - P. A. de Jong
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - A. M. R. Schilham
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - C. Bos
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - J. M. P. J. Breur
- Department of Pediatric Cardiology, Utrecht University Medical Center, Utrecht, The Netherlands
| | - T. Leiner
- Department of Radiology, Utrecht University Medical Center, Utrecht, The Netherlands
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Habets J, Zandvoort HJA, Moll FL, Bartels LW, Vonken EPA, van Herwaarden JA, Leiner T. Magnetic Resonance Imaging with a Weak Albumin Binding Contrast Agent can Reveal Additional Endoleaks in Patients with an Enlarging Aneurysm after EVAR. Eur J Vasc Endovasc Surg 2015; 50:331-40. [PMID: 26036808 DOI: 10.1016/j.ejvs.2015.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 04/09/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVES/BACKGROUND To examine the additional diagnostic value of magnetic resonance imaging (MRI) after administration of a weak albumin binding contrast agent in post-endovascular aneurysm repair (EVAR) patients with aneurysm growth with no or uncertain endoleak after computed tomography angiography (CTA). METHODS This was a prospective diagnostic cross sectional study carried out between April 2011 and August 2013. MRI was performed in all patients with aneurysm growth≥5 mm after EVAR implantation and no or uncertain endoleak on CTA, or the inability, on CTA, to identify the source of a visible endoleak. All MRI scans were performed on a 1.5 T clinical MRI scanner after administration of a weak albumin binding contrast agent. The presence of endoleaks was assessed by visually comparing pre- and post-contrast T1-weighted images with fat suppression. Post-contrast images were acquired 5 and 15 minutes after contrast administration. RESULTS Twenty-nine patients (26 men; 90%) with a median age of 74 years (interquartile range [IQR] 67-76) were included. The median interval between EVAR and MRI was 39 months (IQR 20-50). The median increase in maximum aneurysm diameter during total follow up after EVAR was 11 mm (IQR 6-17). At CTA, 16 patients (55%) had no detectable endoleak, five patients (17%) had suspected but uncertain endoleak, and eight patients had a definite endoleak (28%). On the post-contrast MRI images, endoleak was observed in 24 patients (83%). In all patients with uncertain endoleak on CTA, endoleak was detected with MRI. For type II endoleaks, feeding vessels were detected in 22/23 patients (96%) and these were all, except one, lumbar arteries. CONCLUSION In patients with enlarging aneurysms of unknown origin after EVAR, MRI with a weak albumin binding contrast agent has additional value for both the detection and determination of the origin of the endoleak.
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Affiliation(s)
- J Habets
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Radiology, Gelre Hospitals, Apeldoorn, The Netherlands.
| | - H J A Zandvoort
- Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - F L Moll
- Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - L W Bartels
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - E P A Vonken
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - J A van Herwaarden
- Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - T Leiner
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
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Welman CJ, Harrison C, Low RS. Contrast-enhanced magnetic resonance angiography of the peripheral arteries: technique, tips, pitfalls and problems. J Med Imaging Radiat Oncol 2013; 57:125-40. [PMID: 23551769 DOI: 10.1111/1754-9485.12027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 10/02/2012] [Indexed: 11/30/2022]
Abstract
Contrast-enhanced magnetic resonance angiography is a reliable way to assess peripheral vascular disease. This article reviews the basic physics behind this technique and discusses our institution's experience with regard to the clinical role, recent advances in image acquisition and use of contrast agents. Problems that can affect image quality and interpretation are also highlighted.
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Affiliation(s)
- Christopher J Welman
- Department of Radiology, Fremantle Hospital and Health Service, Fremantle, Western Australia, Australia
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13
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Habets J, Zandvoort HJA, Reitsma JB, Bartels LW, Moll FL, Leiner T, van Herwaarden JA. Magnetic resonance imaging is more sensitive than computed tomography angiography for the detection of endoleaks after endovascular abdominal aortic aneurysm repair: a systematic review. Eur J Vasc Endovasc Surg 2013; 45:340-50. [PMID: 23403221 DOI: 10.1016/j.ejvs.2012.12.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 12/21/2012] [Indexed: 12/14/2022]
Abstract
OBJECTIVES The purpose of this systematic review was to examine whether magnetic resonance imaging (MRI) or computed tomography angiography (CTA) is more sensitive for the detection of endoleaks in patients with abdominal aortic aneurysm (AAA) after EVAR. DESIGN Systematic review. MATERIALS AND METHODS A systematic electronic search was performed. Articles were included when post-EVAR patients were evaluated by both MRI as index test and CTA as comparison. Methodological quality was assessed with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. Primary outcome was the proportion of patients in whom MRI detected additional endoleaks, which were not seen with CTA. RESULTS Eleven articles were included. The overall methodological quality of the articles was good. In total, 369 patients with 562 MRI and 562 CTA examinations were included. A total of 146 endoleaks were detected by CTA; MRI detected all but two of these endoleaks. With MRI 132 additional endoleaks were found. CONCLUSIONS MRI is more sensitive compared to CTA for the detection of post-EVAR endoleaks, especially for the detection of type II endoleaks. MRI should be considered in patients with continued AAA growth and negative or uncertain findings at CTA.
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Affiliation(s)
- J Habets
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, HP E01.132, 3508 GA Utrecht, The Netherlands.
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Cornelissen SA, Verhagen HJ, van Herwaarden JA, Vonken EJP, Moll FL, Bartels LW. Lack of thrombus organization in nonshrinking aneurysms years after endovascular abdominal aortic aneurysm repair. J Vasc Surg 2012; 56:938-42. [DOI: 10.1016/j.jvs.2012.03.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 02/27/2012] [Accepted: 03/04/2012] [Indexed: 10/28/2022]
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15
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Rengier F, Delles M, Unterhinninghofen R, Ley S, Partovi S, Dillmann R, Kauczor HU, von Tengg-Kobligk H. Impact of an aortic nitinol stent graft on flow measurements by time-resolved three-dimensional velocity-encoded MRI. Acad Radiol 2012; 19:274-80. [PMID: 22177284 DOI: 10.1016/j.acra.2011.10.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 10/18/2011] [Accepted: 10/24/2011] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES Three-dimensional (3D) velocity-encoded cine (VEC) magnetic resonance imaging (MRI) has the potential to quantify 3D hemodynamic aspects known from computational fluid dynamics and to be used to identify hemodynamic risk factors for complications of endovascular aortic repair. The purpose of this study was to investigate the impact of an aortic nickel-titanium (nitinol) stent graft on the accuracy of flow measurements by 3D VEC MRI. MATERIALS AND METHODS A pump generated pulsatile aortic flow in an elastic tube phantom mimicking the aorta. Stacked two-dimensional three-directional VEC MRI (stacked-2D-3dir-MRI), 3D three-directional VEC MRI (3D-3dir-MRI), and gold-standard 2D through-plane VEC MRI were applied before and after the insertion of an aortic nitinol stent graft. Six equidistant levels were analyzed twice by the same reader. The percentage difference of the measured flow rate from the gold standard was defined as the parameter of accuracy. RESULTS The overall accuracy of in-stent flow measurements related to the gold standard was -5.4% for stacked-2D-3dir-MRI and -4.1% for 3D-3dir-MRI, demonstrating significant overall underestimation compared to the gold standard (P = .016 and P = .013). However, flow measurements with the stent graft were significantly overestimated by 4.1% using stacked-2D-3dir-MRI (P < .001) and by 5.4% using 3D-3dir-MRI (P = .003) compared to identical measurements without the stent graft. In stacked-2D-3dir-MRI, this positive bias was significantly greater at the proximal and distal ends of the stent graft (P = .025). In 3D-3dir-MRI, measurements along the whole length of the stent graft were affected (P = .006). Intraobserver agreement was excellent, with intraclass correlation coefficients of 0.94 for stacked-2D-3dir-MRI (P < .001) and 0.90 for 3D-3dir-MRI (P < .001). CONCLUSIONS Flow measurements within an aortic nitinol stent graft by 3D VEC MRI are feasible, but stent grafts may cause a significant positive bias.
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Noninvasive Imaging After Stent-Assisted Coiling of Intracranial Aneurysms. J Comput Assist Tomogr 2011; 35:573-82. [DOI: 10.1097/rct.0b013e318224e528] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Cornelissen SA, van der Laan MJ, Vincken KL, Vonken EJPA, Viergever MA, Bakker CJ, Moll FL, Bartels LW. Use of Multispectral MRI to Monitor Aneurysm Sac Contents After Endovascular Abdominal Aortic Aneurysm Repair. J Endovasc Ther 2011; 18:274-9. [DOI: 10.1583/10-3271.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Varma G, Clough RE, Acher P, Sénégas J, Dahnke H, Keevil SF, Schaeffter T. Positive visualization of implanted devices with susceptibility gradient mapping using the original resolution. Magn Reson Med 2010; 65:1483-90. [DOI: 10.1002/mrm.22710] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Revised: 09/27/2010] [Accepted: 10/08/2010] [Indexed: 12/27/2022]
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Walker TG, Kalva SP, Yeddula K, Wicky S, Kundu S, Drescher P, d'Othee BJ, Rose SC, Cardella JF. Clinical Practice Guidelines for Endovascular Abdominal Aortic Aneurysm Repair: Written by the Standards of Practice Committee for the Society of Interventional Radiology and Endorsed by the Cardiovascular and Interventional Radiological Society of Europe and the Canadian Interventional Radiology Association. J Vasc Interv Radiol 2010; 21:1632-55. [DOI: 10.1016/j.jvir.2010.07.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 05/24/2010] [Accepted: 07/11/2010] [Indexed: 12/17/2022] Open
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In vitro validation of flow measurements in an aortic nitinol stent graft by velocity-encoded MRI. Eur J Radiol 2010; 80:163-7. [PMID: 20888719 DOI: 10.1016/j.ejrad.2010.08.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Accepted: 08/26/2010] [Indexed: 11/23/2022]
Abstract
PURPOSE To validate flow measurements within an aortic nickel-titanium (nitinol) stent graft using velocity-encoded cine magnetic resonance imaging (VEC MRI) and to assess intraobserver agreement of repeated flow measurements. MATERIALS AND METHODS An elastic tube phantom mimicking the descending aorta was developed with the possibility to insert an aortic nitinol stent graft. Different flow patterns (constant, sinusoidal and pulsatile aortic flow) were applied by a gear pump. A two-dimensional phase-contrast sequence was used to acquire VEC perpendicular cross-sections at six equidistant levels along the phantom. Each acquisition was performed twice with and without stent graft, and each dataset was analysed twice by the same reader. The percental difference of the measured flow volume to the gold standard (pump setting) was defined as the parameter for accuracy. Furthermore, the intraobserver agreement was assessed. RESULTS Mean accuracy of flow volume measurements was -0.45±1.63% without stent graft and -0.18±1.45% with stent graft. Slightly lower accuracy was obtained for aortic flow both without (-2.31%) and with (-1.29%) stent graft. Accuracy was neither influenced by the measurement position nor by repeated acquisitions. There was significant intraobserver agreement with an intraclass correlation coefficient of 0.87 (without stent graft, p<0.001) and 0.80 (with stent graft, p<0.001). The coefficient of variance was 0.25% without stent graft and 0.28% with stent graft. CONCLUSION This study demonstrated high accuracy and excellent intraobserver agreement of flow measurements within an aortic nitinol stent graft using VEC MRI. VEC MRI may give new insights into the haemodynamic consequences of endovascular aortic repair.
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Detection of Occult Endoleaks After Endovascular Treatment of Abdominal Aortic Aneurysm Using Magnetic Resonance Imaging With a Blood Pool Contrast Agent. Invest Radiol 2010; 45:548-53. [DOI: 10.1097/rli.0b013e3181e992ac] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Volders D, Fourneau I, Daenens K, Houthoofd S, Maleux G, Nevelsteen A. Paraparesis after thoracic stent-graft relining for an unrecognized type III endoleak. Ann Vasc Surg 2010; 24:550.e5-9. [PMID: 20129755 DOI: 10.1016/j.avsg.2009.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 08/20/2009] [Accepted: 08/27/2009] [Indexed: 11/25/2022]
Abstract
BACKGROUND We examined the reasons for missing a type III endoleak on conventional imaging and the pathophysiology of paraparesis after relining this stent graft. METHODS AND RESULTS A 46-year-old man was treated with a thoracic stent graft for thoracic rupture of a chronic type B thoracoabdominal dissection with aneurysm formation. In a second intervention, retrograde revascularization of the visceral and renal arteries was performed in combination with insertion of an abdominal stent graft. After initial shrinkage of the aneurysmal sac, the thoracic aortic diameter started increasing again. Consecutive three-phase helical computed tomographic scans did not reveal any endoleak. Because of unbearable back pain, an open surgical exploration was performed. This showed a type III endoleak. Relining of the thoracic stent graft was performed, but paraparesis developed. CONCLUSION In patients with unexplained increase of the aneurysmal sac contrast-enhanced magnetic resonance imaging could help to illuminate the underlying endoleak. The collateral network concept can explain spinal cord injury by even minor hemodynamic changes.
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Affiliation(s)
- David Volders
- Department of Vascular Surgery, University Hospital Leuven, B-3000 Leuven, Belgium
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23
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Dynamics of the Aorta Before and After Endovascular Aneurysm Repair: A Systematic Review. Eur J Vasc Endovasc Surg 2009; 38:586-96. [DOI: 10.1016/j.ejvs.2009.06.018] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Accepted: 06/26/2009] [Indexed: 11/20/2022]
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Hope TA, Zarins CK, Herfkens RJ. Initial experience characterizing a type I endoleak from velocity profiles using time-resolved three-dimensional phase-contrast MRI. J Vasc Surg 2009; 49:1580-4. [DOI: 10.1016/j.jvs.2009.01.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 12/22/2008] [Accepted: 01/03/2009] [Indexed: 11/16/2022]
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Ratnayaka K, Faranesh AZ, Guttman MA, Kocaturk O, Saikus CE, Lederman RJ. Interventional cardiovascular magnetic resonance: still tantalizing. J Cardiovasc Magn Reson 2008; 10:62. [PMID: 19114017 PMCID: PMC2637847 DOI: 10.1186/1532-429x-10-62] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Accepted: 12/29/2008] [Indexed: 12/30/2022] Open
Abstract
The often touted advantages of MR guidance remain largely unrealized for cardiovascular interventional procedures in patients. Many procedures have been simulated in animal models. We argue these opportunities for clinical interventional MR will be met in the near future. This paper reviews technical and clinical considerations and offers advice on how to implement a clinical-grade interventional cardiovascular MR (iCMR) laboratory. We caution that this reflects our personal view of the "state of the art."
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Affiliation(s)
- Kanishka Ratnayaka
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
- Cardiology Division, Children's National Medical Center, Washington, DC, USA
| | - Anthony Z Faranesh
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Michael A Guttman
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Ozgur Kocaturk
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Christina E Saikus
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Robert J Lederman
- Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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Levine GN, Gomes AS, Arai AE, Bluemke DA, Flamm SD, Kanal E, Manning WJ, Martin ET, Smith JM, Wilke N, Shellock FS. Safety of magnetic resonance imaging in patients with cardiovascular devices: an American Heart Association scientific statement from the Committee on Diagnostic and Interventional Cardiac Catheterization, Council on Clinical Cardiology, and the Council on Cardiovascular Radiology and Intervention: endorsed by the American College of Cardiology Foundation, the North American Society for Cardiac Imaging, and the Society for Cardiovascular Magnetic Resonance. Circulation 2007; 116:2878-91. [PMID: 18025533 DOI: 10.1161/circulationaha.107.187256] [Citation(s) in RCA: 311] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Advances in magnetic resonance (MR) imaging over the past 2 decades have led to MR becoming an increasingly attractive imaging modality. With the growing number of patients treated with permanent implanted or temporary cardiovascular devices, it is becoming ever more important to clarify safety issues in regard to the performance of MR examinations in patients with these devices. Extensive, although not complete, ex vivo, animal, and clinical data are available from which to generate recommendations regarding the safe performance of MR examination in patients with cardiovascular devices, as well as to ascertain caveats and contraindications regarding MR examination for such patients. Safe MR imaging involves a careful initial patient screening, accurate determination of the permanent implanted or temporary cardiovascular device and its properties, a thoughtful analysis of the risks and benefits of performing the examination at that time, and, when indicated, appropriate physician management and supervision. This scientific statement is intended to summarize and clarify issues regarding the safety of MR imaging in patients with cardiovascular devices.
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Abstract
Rapid, noninvasive imaging approaches can provide novel diagnostic information and, when effectively interpreted and implemented in a therapeutic strategy, can simplify procedures. Endovascular therapy of thoracic and abdominal aortic disease represents a dramatic shift in treatment of thoracoabdominal aortic disease, but one that requires a change in the knowledge base regarding both the morphology and pathophysiology of aortic disease and the interaction with interventional devices. As a result, the demands on cross-sectional imaging have increased commensurately with the complexity of the therapeutic options, but advances in cross-sectional imaging have kept pace. Current computed tomography (CT) and magnetic resonance imaging (MRI) technologies provide detailed morphologic assessment, and are advancing rapidly into more sophisticated physiologic evaluation of aortic disease. These advances may more effectively triage patients to appropriate therapy, or exclude patients from unnecessary invasive procedures. The information gleaned from CT and MRI studies is critical for the vascular surgeon who wants to identify appropriate vascular territories for intervention, plan a detailed approach, and develop sophisticated surveillance strategies.
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MESH Headings
- Aorta/pathology
- Aorta/physiopathology
- Aorta/surgery
- Aortic Aneurysm, Abdominal/diagnosis
- Aortic Aneurysm, Abdominal/physiopathology
- Aortic Aneurysm, Abdominal/surgery
- Aortic Aneurysm, Thoracic/diagnosis
- Aortic Aneurysm, Thoracic/physiopathology
- Aortic Aneurysm, Thoracic/surgery
- Aortography/methods
- Compliance
- Contrast Media/adverse effects
- Coronary Angiography/methods
- Humans
- Imaging, Three-Dimensional
- Kidney Diseases/chemically induced
- Magnetic Resonance Angiography/adverse effects
- Magnetic Resonance Imaging, Interventional
- Patient Selection
- Radiation Injuries/etiology
- Radiographic Image Interpretation, Computer-Assisted
- Radiography, Interventional
- Tomography, X-Ray Computed/adverse effects
- Vascular Surgical Procedures
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Affiliation(s)
- Scott D Flamm
- Cardiovascular Imaging, Department of Radiology, Cleveland Clinic, Cleveland, OH 44195, USA.
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28
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Schwope RB, Alper HJ, Talenfeld AD, Cohen EI, Lookstein RA. MR angiography for patient surveillance after endovascular repair of abdominal aortic aneurysms. AJR Am J Roentgenol 2007; 188:W334-40. [PMID: 17377001 DOI: 10.2214/ajr.06.0584] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The objective of this article is to demonstrate how new imaging sequences and techniques allow characterization of postoperative complications after endovascular surgery and offer the physician more information for planning treatment than ever before. CONCLUSION MR angiography is an excellent technique for the surveillance of patients after endovascular repair of abdominal aortic aneurysms because it is highly sensitive for the detection of postoperative complications. A thorough knowledge of the physical properties of the endovascular components is essential to choose the appropriate patients for this form of surveillance.
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Affiliation(s)
- Ryan B Schwope
- Department of Interventional Radiology, Mount Sinai Medical Center, One Gustave L. Levy Pl., Box 1234, New York, NY 10029, USA
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Teutelink A, Muhs BE, Vincken KL, Bartels LW, Cornelissen SA, van Herwaarden JA, Prokop M, Moll FL, Verhagen HJM. Use of dynamic computed tomography to evaluate pre- and postoperative aortic changes in AAA patients undergoing endovascular aneurysm repair. J Endovasc Ther 2007; 14:44-9. [PMID: 17291151 DOI: 10.1583/06-1976.1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To utilize dynamic computed tomographic angiography (CTA) on pre- and postoperative endovascular aneurysm repair (EVAR) patients to characterize cardiac-induced aortic motion within the aneurysm neck, an essential EVAR sealing zone. METHODS Electrocardiographically-gated CTA datasets were acquired utilizing a 64-slice Philips Brilliance CT scanner on 15 consecutive pre- and postoperative AAA patients. Axial pulsatility measurements were taken at 2 clinically relevant levels within the aneurysm neck: 2 cm above the highest renal artery and 1 cm below the lowest renal artery. Changes in aortic area and diameter were determined. RESULTS Significant aortic pulsatility exists within the aneurysm neck during the cardiac cycle. Preoperative aortic area increased significantly, with a maximum increase of up to 12.5%. The presence of an endograft did not affect aortic pulsatility (p=NS). Postoperative area also changed significantly during a heart cycle, with a maximum increase of up to 14.5%. Diameter measurements demonstrated an identical pattern, with significant pre- and postoperative intracardiac pulsatility within and above the aneurysm neck (p<0.05). An increase in maximum diameter change up to 15% was evident. CONCLUSION Patients undergoing EVAR experience aortic diameter changes within and above the aneurysm neck. The presence of an endograft does not abrogate this response to intracardiac pressure changes. Static CT imaging may not adequately identify patients with large aortic pulsatility, potentially resulting in endograft undersizing, stent-graft migration, intermittent type I endoleaks, and poor patient outcomes. The current standard regime of 10% to 15% oversizing based on static CT may be inadequate for some patients.
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Affiliation(s)
- Arno Teutelink
- Departments of Vascular Surgery, University Medical Center, Utrecht, The Netherlands
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Hiramoto JS, Reilly LM, Schneider DB, Skorobogaty H, Rapp J, Chuter TAM. The effect of magnetic resonance imaging on stainless-steel Z-stent–based abdominal aortic prosthesis. J Vasc Surg 2007; 45:472-4. [PMID: 17254740 DOI: 10.1016/j.jvs.2006.11.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2006] [Accepted: 11/08/2006] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To assess the effects of magnetic resonance imaging (MRI) on stainless-steel Z-stent-based abdominal aortic prostheses. METHODS From June 1996 to December 2005, 550 patients underwent endovascular repair of an infrarenal abdominal aortic aneurysm at a single academic institution by using a stainless-steel Z-stent-based abdominal aortic prosthesis. Routine patient follow-up included computed tomography scans and abdominal plain films at 1, 6, and 12 months after surgery and yearly thereafter. Although patients were specifically instructed not to undergo MRI, retrospective review identified 22 patients (4%) who underwent MRI after stent-graft implantation. RESULTS Seventeen of 22 patients consented to have their records reviewed as part of this study and underwent MRI at a mean interval of 669 days (range, 3-2179 days) after stent-graft implantation. Eleven patients underwent implantation of Zenith bifurcated stent grafts, and six had custom-made uni-iliac stent grafts. These patients underwent a total of 20 MRI studies-10 of the brain/neck and 10 of the abdomen, pelvis, or spine. In all cases, the magnetic field strength was 1.5 T or less. No patient experienced any symptoms of abdominal or back pain during or after the MRI. Comparison of the pre- and post-MRI computed tomography scans (available in 15 of 17 patients) and abdominal radiographs showed no change in stent-graft structure, position, or function in any of these patients and no increase in abdominal aortic aneurysm diameter in any patient at an average of 899 days after MRI. CONCLUSIONS On the basis of this limited experience, MRI has no discernible effect on the structure, position, or function of stainless-steel Z-stent-based abdominal aortic prostheses.
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Affiliation(s)
- Jade S Hiramoto
- Division of Vascular Surgery, University of California-San Francisco, San Francisco, CA 94143, USA.
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van Herwaarden JA, Muhs BE, Vincken KL, van Prehn J, Teutelink A, Bartels LW, Moll FL, Verhagen HJM. Aortic compliance following EVAR and the influence of different endografts: determination using dynamic MRA. J Endovasc Ther 2006; 13:406-14. [PMID: 16784330 DOI: 10.1583/06-1848.1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To utilize dynamic magnetic resonance angiography (MRA) to characterize aortic stiffness (beta) and elastic modulus (Ep) as indexes of wall compliance during the cardiac cycle and determine any influence of different endograft designs or the presence of endoleaks on these indexes. METHODS Eleven consecutive patients (11 men; median age 74 years, range 63-78) with abdominal aortic aneurysm (AAA) selected for endovascular repair were scanned pre- and postoperatively. Aortic area and diameter changes during the cardiac cycle were determined using dynamic MRA at 4 levels: 3 cm above the renal arteries, between the renal arteries, 1 cm below the renal arteries, and at the level of maximum aneurysm sac diameter. Ep and beta were calculated. Data are presented as median (range); p<0.05 was considered significant. RESULTS Preoperatively, Ep and beta were significantly higher at the level of the aneurysm sac compared to all other levels (p<0.05). Following EVAR, stiffness increased at this level (p<0.05). After implantation, patients with an Excluder endograft demonstrated Ep and beta measurements at the aneurysm neck that were 94% and 60% higher, respectively, compared to those with a Talent (p<0.05) endograft. The presence of an endoleak had no effect on Ep or beta. CONCLUSION This study introduces the feasibility of dynamic MRA imaging-based calculations of aortic elastic modulus and stiffness. AAA patients demonstrate increased Ep and beta at the level of the aneurysm sac. EVAR results in increased aneurysm sac Ep and beta. Stent-graft design seems to alter Ep and beta within the aneurysm neck, which may have consequences for endograft durability. The presence of an endoleak does not seem to have an effect on Ep or beta.
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Eggebrecht H, Heusch G, Erbel R, Ladd ME, Quick HH. Real-time vascular interventional magnetic resonance imaging. Basic Res Cardiol 2006; 102:1-8. [PMID: 17006635 DOI: 10.1007/s00395-006-0624-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Accepted: 08/14/2006] [Indexed: 11/26/2022]
Abstract
Endovascular stent-graft placement is emerging as a promising alternative to medical and surgical treatment of patients with diseases of the descending thoracic and abdominal aorta. Precise placement of the stentgraft, which is currently performed under x-ray control, remains, however, challenging as there are several shortcomings to fluoroscopic guidance beyond that related to the harmful effect of radiation exposure and nephrotoxic contrast media. While transesophageal echocardiography and intravascular ultrasound have been used as adjunct imaging modalities during endovascular stent-graft procedures to overcome the limitations of angiography, these techniques have not mitigated the need for fluoroscopy. Magnetic resonance imaging (MRI) guidance of vascular interventional procedures offers several potential advantages over fluoroscopy-guided techniques, including image acquisition in any desired orientation, superior 3D soft-tissue contrast with simultaneous visualization of the interventional device, absence of ionizing radiation, and avoidance of nephrotoxic contrast media. Magnetic resonance imaging is often used for pre-operative diagnosis of aortic disease and can provide all relevant information for the planning of endovascular stent-graft procedures as well as for accurate and immediate post-interventional evaluation. However, visualization of interventional instruments by MRI has proven to be the chief obstacle. This article will review current approaches that have been developed for depicting vascular instruments by MRI and will also discuss the first experimental experiences with MRI-guided endovascular stent-graft placement in a swine model of aortic dissection.
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Affiliation(s)
- Holger Eggebrecht
- Klinik für Kardiologie, Westdeutsches Herzzentrum Essen, Klinikum der Universität Duisburg-Essen, Essen, Germany.
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van Herwaarden JA, Bartels LW, Muhs BE, Vincken KL, Lindeboom MYA, Teutelink A, Moll FL, Verhagen HJM. Dynamic magnetic resonance angiography of the aneurysm neck: Conformational changes during the cardiac cycle with possible consequences for endograft sizing and future design. J Vasc Surg 2006; 44:22-8. [PMID: 16828422 DOI: 10.1016/j.jvs.2006.03.028] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 03/03/2006] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Proper proximal fixation and stent-graft sealing within the aneurysm neck are critical for endovascular aneurysm repair (EVAR) durability. Computed tomography angiography (CTA) is the gold standard for preoperative sizing of endograft diameters, but the accuracy of these measurements is uncertain because they rely on static images of a dynamic process. The aortic configuration and diameter may change during the cardiac cycle. We studied these phenomena using dynamic electrocardiograph-triggered magnetic resonance angiography (MRA). METHODS Eleven consecutive EVAR patients were included. Dynamic MRA was used to perform preoperative and postoperative measurements. Changes were measured in transverse aortic sections 10 mm below the lowest renal artery (level A), at the level of the renal arteries (level B), and 3 cm above the lowest renal artery (level C). Data were analyzed using image segmentation software. Aortic area and diameter changes along 256 axes were determined. RESULTS Dynamic MRA demonstrated significant aortic area changes during the cardiac cycle before and after EVAR at all three measured levels. Pre-EVAR aortic area significantly increased per cardiac cycle: 8.4% at level A; 9.3% at level B; and 13.3% at level C (P < .001 for all levels). Post-EVAR aortic area increased 9.7% at level A, 9.6% at level B, and 15.8% at level C per cardiac cycle (P < .001 for all levels). Significant diameter changes during cardiac cycles were also observed at all three levels. Pre-EVAR mean diameter changed up to 8.9% (P < .001) compared with post-EVAR aortic changes of up to 11.5% (P < .001). EVAR had no effect on change in aortic area and diameter. Dynamic MRA also demonstrated that pulsatile aortic distension was not equal in all axes, but rather occurred as an asymmetrical expansion and contraction. CONCLUSION In patients with (atherosclerotic) aneurysm disease, the aortic dimensions at the level of and proximal to the aneurysm neck change during the cardiac cycle. This phenomenon is preserved after EVAR. Therefore, maximum diameter using dynamic MRA may not be similar to the maximum diameter with static CTA in all patients, and a standard regimen of 10% to 15% oversizing of an endograft based on static CTA images may be inadequate for some patients. Further studies using dynamic MRA to evaluate effects of different endografts are anticipated, with possible consequences for endograft designs.
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Affiliation(s)
- Joost A van Herwaarden
- Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
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Guidoin R, Zhang Z, Douville Y, Bonny JM, Renou JP, Baslé MF, Zarins CK, Legrand AP, Guzman R. MRI virtual biopsies: analysis of an explanted endovascular device and perspectives for the future. ACTA ACUST UNITED AC 2006; 34:241-61. [PMID: 16537177 DOI: 10.1080/10731190600581825] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Information that can be obtained by magnetic resonance imaging (MRI) of explanted endovascular devices must be validated as this method is non-destructive. Histology of such a device together with its encroached tissues can be elegantly performed after polymethymethacrylate (PMMA) embedding, but this approach requires destruction of the specimen. The issue is therefore to determine if the MRI is sufficient to fully validate an explanted device based upon the characterization of an explanted specimen. An AneuRx device deployed percutaneously 25 months earlier in a 75-year-old patient was removed en bloc at autopsy together with the surrounding aneurysmal sac and segments of the upstream and downstream arteries. Macroscopic pictures were taken and a slice of the cross-section was processed for histology after polymethylmethacrylate (PMMA) embedding. For the magnetic resonance imaging investigation, the device was inserted in a Biospec 4.7 T MRI system with a 20 mm diameter birdcage resonator used for both emission and reception. A Spin-Echo (SE) was used to acquire both T1 proton density (PD) and T2 weighted images. A gradient-echo (GE) sampling of a free induction decay (GESFID) was used to generate multiple GE images using a single excitation pulse so that four images at different TE were obtained in the same acquisition. The selected explanted device was outstandingly well-healed compared to most devices harvested from humans. No inflammatory process was observed in contact or at distance of the materials. In MRI T1 images display no specific contrast and were homogeneous in the different tissues. The contrast was improved on proton density weighed images. On the T2 weighed images, the different areas were well identified. The diffusion images displayed in the surrounding B region had the greatest diffusion coefficient and the greatest anisotropy. The MRI analysis of the explanted AneuRx device illustrates the possibilities of this technique to characterize the interaction of the endovascular graft with the surrounding tissues. MRI is a breakthrough to investigate explanted medical devices but it also can be advantageously used in vivo to obtain virtual biopsies, because real biopsies to determine the 3 Bs (biocompatibility, biofunctionality and bioresilience) cannot be carried out as they could obviously initiate infection and degradation of the foreign materials.
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Affiliation(s)
- R Guidoin
- Department of Surgery, Laval University and Quebec Biomaterials Institute, St. François d'Assise Hospital, Quebec, Canada.
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Abstract
Frequent and sustained surveillance continues to be mandated for all patients who undergo endovascular repair of the aneurysmal aorta in order to minimize the small but attendant risk of aneurysm rupture. The primary motivation for surveillance includes evaluation of residual aneurysm sac size and presence of endoleak, as well as potential adverse device specific events, such as endograft migration, module disconnection, or component fatigue and failure. The current standard of care and future surveillance modalities after endovascular repair of both abdominal aortic and thoracic aortic aneurysms will be reviewed.
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Affiliation(s)
- Ross Milner
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Emory University School of Medicine, Atlanta, GA, USA.
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van der Laan MJ, Bartels LW, Viergever MA, Blankensteijn JD. Computed tomography versus magnetic resonance imaging of endoleaks after EVAR. Eur J Vasc Endovasc Surg 2006; 32:361-5. [PMID: 16630731 DOI: 10.1016/j.ejvs.2006.02.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Accepted: 02/14/2006] [Indexed: 10/24/2022]
Abstract
AIM The aim of study was to compare the sensitivity of MRI and CTA for endoleak detection and classification after EVAR. PATIENTS & METHODS Twenty-eight patients, between 2 days and 65 months after EVAR, were evaluated with both CT and MRI. Twenty-five patients had an Ancure graft and the other three had an Excluder. The MRI protocol for endoleak evaluation included: a T1-weighted spin echo, a high-resolution 3D CE-MRA, and a post-contrast T1-weighted spin echo. In total 40 ml Gadolinium was administered. The CT protocol consisted of a blank survey followed by a spiral CT angiography (CTA) using 140 ml of Ultravist. An experienced, blinded observer evaluated all CTs and MRIs. RESULTS Using MRI and MRA techniques significantly more endoleaks (23/35) were detected than with CTA (11/35) (p=0.01, Chi-Square). CT could not determine the type of endoleak in 3 of the 11 endoleaks detected and was uncertain in one. MRI was uncertain about the type in 14 of the 23 endoleaks detected. All endoleaks visible on CT were visible by MRI as well. CONCLUSIONS MRI techniques are more sensitive for the detection of endoleak after endovascular AAA repair than CT.
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Affiliation(s)
- M J van der Laan
- Department of Vascular Surgery, University Medical Center, Utrecht, The Netherlands.
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van den Berg HR, Leijdekkers VJ, Vahl A. Aortic Stent-Graft Infection Following Septic Complications of a Kidney Stone. Cardiovasc Intervent Radiol 2006; 29:443-5. [PMID: 16502167 DOI: 10.1007/s00270-005-0028-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A 73-year-old man was treated because of a renal pelvis blowout of the left kidney for which he received a nephrostomy catheter without antibiotic prophylaxis. Almost a year previously this patient had undergone endovascular repair of a symptomatic infrarenal abdominal aorta aneurysm. Four weeks after the diagnosis and treatment of the ruptured renal pelvis, a new computed tomography scan and ultrasound-guided fine needle aspiration confirmed the diagnosis of infected aortic stent-graft. An extra-anatomic axillo-uniiliac bypass and graft excision was performed. Two weeks after discharge the patient returned to the hospital with an occlusion of his left renal artery and died of renal failure. This is the first time an infected aortic stent-graft after a renal pelvis blowout has been reported. Although infections of aortic stent-grafts occur rarely, one should be aware of the possibility in aortic stent-graft patients undergoing abdominal procedures without antibiotic prophylaxis.
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Affiliation(s)
- H Rogier van den Berg
- Department of Vascular Surgery, Onze Lieve Vrouwe Gasthuis, Amsterdam, HA, The Netherlands.
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Eggebrecht H, Zenge M, Ladd ME, Erbel R, Quick HH. In Vitro Evaluation of Current Thoracic Aortic Stent-Grafts for Real-time MR-Guided Placement. J Endovasc Ther 2006; 13:62-71. [PMID: 16445325 DOI: 10.1583/05-1707.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To systematically evaluate the magnetic resonance imaging (MRI) characteristics of current thoracic aortic stent-graft devices before, during, and after in vitro deployment as a step toward real-time MRI-guided stent placement. METHODS Six stent-graft devices used for thoracic aortic repair were examined in a dedicated phantom model using a 1.5-T MRI scanner. First, the delivery systems with the mounted stent-graft were examined using real-time fast imaging with steady-state precession (TrueFISP) with Cartesian and radial k-space filling. TrueFISP imaging was subsequently used for real-time monitoring of stent-graft expansion. The deployed stent-grafts were then examined in a water bath containing gadolinium (1:40) with high-resolution T1-weighted 3D fast low-angle shot (FLASH) sequences. The images were analyzed for artifacts, radiofrequency caging effects, and device visualization quality. RESULTS Three delivery systems with mounted stent-grafts did not contain ferromagnetic elements and were well visualized. Imaging with radial k-space filling showed fewer artifacts than Cartesian imaging. Movement of the delivery system and stent-graft expansion of these devices were successfully demonstrated at a rate of up to 6 frames per second. Evaluation of the expanded stent-grafts revealed only minor susceptibility artifacts without relevant signal attenuation in the stent-graft lumen for 5 nitinol-based stent-grafts. Only a stainless steel-based stent-graft was associated with severe artifacts, thwarting visualization of its lumen or surroundings. CONCLUSION The present study shows that 3 nitinol-based thoracic stent-graft devices are potentially suited for real-time MRI-guided placement with respect to both the delivery system and the stent-graft itself. These observations provide the basis for the evaluation of MRI-guided stent-graft placement in vivo.
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Affiliation(s)
- Holger Eggebrecht
- Department of Cardiology, West German Heart Center Essen, University of Duisburg-Essen, Germany.
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Adams GJ, Baltazar U, Karmonik C, Bordelon C, Lin PH, Bush RL, Lumsden AB, Morrisett JD. Comparison of 15 different stents in superficial femoral arteries by high resolution MRI ex vivo and in vivo. J Magn Reson Imaging 2005; 22:125-35. [PMID: 15971171 DOI: 10.1002/jmri.20359] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
PURPOSE To evaluate the MRI compatibility of 15 different commercially available, new generation, U.S. Food and Drug Administration (FDA)-approved stents suitable for deployment in superficial femoral arteries (SFAs), and to identify the ones that permit MRI to visualize the wall and lumen of stented arteries with sufficient spatial and contrast resolution to quantify restenosis after stent placement. MATERIALS AND METHODS A total of 13 nitinol stents and two stainless-steel stents were placed in excised cadaveric SFAs and imaged by MRI at 1.5 T ex vivo. The images were evaluated qualitatively for the presence of artifacts and for the effects of the stent on image contrast, and quantitatively for the effect on signal-to-noise ratio (SNR) of the lumen of the artery inside the stent compared to the SNR of the fluid outside the artery. A nitinol stent was placed in the SFA of a 60-year-old man and imaged at 1.5 T in vivo. RESULTS Both the vessel wall and the lumen could be visualized in cadaveric SFAs containing either the Absolute nitinol stent, the Dynalink nitinol stent, or the aSpire nitinol-covered stent. Their inside stent/outside stent SNR was 0.7, 0.8, and 0.8, respectively. The other 10 nitinol stents tested obscured the lumen but did not cause major image shape artifacts. Both stainless-steel stents tested, the WallGraft and WallStent, completely obscured the lumen and caused significant distortion of the image shapes. When the Dynalink stent was inserted into a highly stenosed SFA in vivo, the image showed a dark expanded eccentric lumen, circumscribed by a medium intensity band containing the stent. CONCLUSION MRI can be used to visualize both the lumen and wall of SFAs containing selected nitinol stents ex vivo and in vivo. These results suggest that MRI can be used to monitor restenosis in stents placed in the femoral arterial bed.
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Affiliation(s)
- Gareth J Adams
- Structural and Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, Texas 77030, USA
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