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Inuzuka N, Shobayashi Y, Tateshima S, Sato Y, Ohba Y, Ekdahl KN, Nilsson B, Teramura Y. Stent coating containing a charged silane coupling agent that regulates protein adsorption to confer antithrombotic and cell-adhesion properties. Sci Rep 2024; 14:15178. [PMID: 38987553 PMCID: PMC11237119 DOI: 10.1038/s41598-024-65832-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 06/24/2024] [Indexed: 07/12/2024] Open
Abstract
The evolution of endovascular therapies, particularly in the field of intracranial aneurysm treatment, has been truly remarkable and is characterized by the development of various stents. However, ischemic complications related to thrombosis or downstream emboli pose a challenge for the broader clinical application of such stents. Despite advancements in surface modification technologies, an ideal coating that fulfills all the desired requirements, including anti-thrombogenicity and swift endothelialization, has not been available. To address these issues, we investigated a new coating comprising 3-aminopropyltriethoxysilane (APTES) with both anti-thrombogenic and cell-adhesion properties. We assessed the anti-thrombogenic property of the coating using an in vitro blood loop model by evaluating the platelet count and the level of the thrombin-antithrombin (TAT) complex, and investigating thrombus formation on the surface using scanning electron microscopy (SEM). We then assessed endothelial cell adhesion on the metal surfaces. In vitro blood tests revealed that, compared to a bare stent, the coating significantly inhibited platelet reduction and thrombus formation; more human serum albumin spontaneously adhered to the coated surface to block thrombogenic activation in the blood. Cell adhesion tests also indicated a significant increase in the number of cells adhering to the APTES-coated surfaces compared to the numbers adhering to either the bare stent or the stent coated with an anti-fouling phospholipid polymer. Finally, we performed an in vivo safety test by implanting coated stents into the internal thoracic arteries and ascending pharyngeal arteries of minipigs, and subsequently assessing the health status and vessel patency of the arteries by angiography over the course of 1 week. We found that there were no adverse effects on the pigs and the vascular lumens of their vessels were well maintained in the group with APTES-coated stents. Therefore, our new coating exhibited both high anti-thrombogenicity and cell-adhesion properties, which fulfill the requirements of an implantable stent.
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Affiliation(s)
- Naoki Inuzuka
- R&D Department, Japan Medical Device Startup Incubation Program, 3-7-2 Nihonbashihon-cho, Chuo-ku, Tokyo, 103-0023, Japan
- R&D Department, N.B. Medical Inc., 3-7-2 Nihonbashihon-cho, Chuo-ku, Tokyo, 103-0023, Japan
| | - Yasuhiro Shobayashi
- R&D Department, N.B. Medical Inc., 3-7-2 Nihonbashihon-cho, Chuo-ku, Tokyo, 103-0023, Japan
| | - Satoshi Tateshima
- Division of Interventional Neuroradiology, Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles (UCLA), Ronald Reagan UCLA Medical Center, 757 Westwood Plaza, Suite 2129, Los Angeles, CA, 90095, USA
| | - Yuya Sato
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Yoshio Ohba
- Cellular and Molecular Biotechnology Research Institute (CMB), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Kristina N Ekdahl
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Bo Nilsson
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden
| | - Yuji Teramura
- Cellular and Molecular Biotechnology Research Institute (CMB), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, 751 85, Uppsala, Sweden.
- Master's/Doctoral Program in Life Science Innovation (T-LSI), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
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Bilgin C, Senol YC, Kobeissi H, Orscelik A, Ghozy S, Oliver AA, Kadirvel R, Brinjikji W, Kallmes DF. Phenox HPC and Phenox flow modulation devices for the endovascular treatment of intracranial aneurysms: a systematic review and meta-analysis. J Neurointerv Surg 2024; 16:706-714. [PMID: 37536930 DOI: 10.1136/jnis-2023-020514] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 07/12/2023] [Indexed: 08/05/2023]
Abstract
BACKGROUND Surface-modified flow diverters are increasingly used in clinical settings. However, their safety profiles and additional benefits over non-coated devices still need to be explored. In this meta-analysis, we aimed to investigate and compare the clinical outcomes of the uncoated Phenox and coated Phenox HPC flow diverters. METHODS A systematic literature review was performed using PubMed, Scopus, Embase, and Web of Science databases. Collected data were pooled and corresponding 95% confidence intervals (CI) were calculated. Outcomes of interest included aneurysm occlusion (>6 months) and complication rates. Additionally, the safety outcomes of prophylactic single (SAPT) and dual antiplatelet treatment (DAPT) approaches were compared for patients treated with coated Phenox HPC flow diverters. RESULTS We included 17 studies with 1238 patients. The overall complete occlusion rates were 80% (95% CI 74.01% to 86.56%) for Phenox HPC and 71.3% (95% CI 59.71% to 85.20%) for non-coated Phenox flow diverters (p=0.24). Ischemic complication rates were 7.3% (95% CI 4.6% to 11.39%) with the Phenox HPC and 5.3% (95% CI 4.07% to 6.91%) with the Phenox (p=0.24). For patients treated with Phenox HPC, the SAPT (5.5%; 95% CI 2.83% to 10.85%) and DAPT (7.1%; 95% CI 1.23% to 41.45%) approaches resulted in comparable ischemic complication rates (p=0.79). The DAPT group (4.8%; 95% CI 1.46% to 16.24%) had higher hemorrhagic complication rates than the SAPT group (1.7%; 95% CI 0.52% to 6.09%), but the difference was not statistically significant for patients treated with Phenox HPC (p=0.25). CONCLUSIONS Our findings indicate that Phenox HPC is equally as safe and effective as non-coated Phenox devices. Additionally, our results suggest that prasugrel monotherapy might effectively prevent ischemic complications in patients treated with Phenox HPC flow diverters.
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Affiliation(s)
- Cem Bilgin
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Yigit Can Senol
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Hassan Kobeissi
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Atakan Orscelik
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Sherief Ghozy
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | - Waleed Brinjikji
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - David F Kallmes
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
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Fiehler J, Ortega-Gutierrez S, Anagnostakou V, Cortese J, Cekirge HS, Fiorella D, Hanel R, Kulcsar Z, Lamin S, Liu J, Lylyk P, Marden FA, Pereira VM, Psychogios MN, Rice H, Rouchaud A, Saatci I, Siddiqui AH, Spelle L, Yang P, Grams A, Gounis MJ. Evaluation of flow diverters for cerebral aneurysm therapy: recommendations for imaging analyses in clinical studies, endorsed by ESMINT, ESNR, OCIN, SILAN, SNIS, and WFITN. J Neurointerv Surg 2024:jnis-2023-021404. [PMID: 38830670 DOI: 10.1136/jnis-2023-021404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 04/02/2024] [Indexed: 06/05/2024]
Abstract
BACKGROUND Multiple studies and meta-analyses have described the technical and clinical outcomes in large cohorts of aneurysm patients treated with flow diverters (FDs). Variations in evaluation methodology complicate making comparisons among studies, hinder understanding of the device behavior, and pose an obstacle in the assessment of further advances in FD therapy. METHODS A multidisciplinary panel of neurointerventionalists, imaging experts, and neuroradiologists convened with the goal of establishing consensus recommendations for the standardization of image analyses in FD studies. RESULTS A standardized methodology is proposed for evaluating and reporting radiological outcomes of FD treatment of intracranial aneurysms. The recommendations include general imaging considerations for clinical studies and evaluations of longitudinal changes, such as neointimal lining and stenosis. They cover standards for classification of aneurysm location, morphology, measurements, as well as the assessment of aneurysm occlusion, wall apposition, and neck coverage. These reporting standards further define four specific braid deformation patterns: foreshortening, fish-mouthing, braid bump deformation, and braid collapse, collectively termed 'F2B2'. CONCLUSIONS When widely applied, standardization of methods of measuring and reporting outcomes will help to harmonize the assessment of treatment outcomes in clinical studies, help facilitate communication of results among specialists, and help enable research and development to focus on specific aspects of FD techniques and technology.
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Affiliation(s)
- Jens Fiehler
- Department of Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Santiago Ortega-Gutierrez
- Neurology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
- Neurosurgery and Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Vania Anagnostakou
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Jonathan Cortese
- Interventional Neuroradiology, Biĉetre Hospital, Le Kremlin Biĉetre, France
- UMR CNRS No. 7252, XLIM, Limoges, France
| | - H Saruhan Cekirge
- Radiology, Koru Health Group, Ankara, Turkey
- Private Office, Saruhan Cekirge, Ankara, Turkey
| | - David Fiorella
- Department of Neurosurgery, Stony Brook University, Stony Brook, New York, USA
| | - Ricardo Hanel
- Stroke & Cerebrovascular Center, Baptist Neurological Institute and Lyerly Neurosurgery, Jacksonville, Florida, USA
| | - Zsolt Kulcsar
- Neuroradiology, University Hospital Zurich, Zurich, Switzerland
| | - Saleh Lamin
- Interventional Neuroradiology and Radiology, Queen Elizabeth Hospital Birmingham, Birmingham, UK
- Neuroradiology, University Hospital Birmingham, Birmingham, UK
| | - Jianmin Liu
- Neurosurgery, Naval Medical University, Shanghai, China
| | - Pedro Lylyk
- Interventional Neuroradiology, Clinical Institute ENERI, Buenos Aires, Argentina
| | | | - Vitor M Pereira
- Department of Neurosurgery, Unity Health Toronto, Toronto, Ontario, Canada
| | - Marios-Nikos Psychogios
- Department of Neuroradiology, Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Hal Rice
- Department of Interventional Neuroradiology, Gold Coast University Hospital, Southport, Queensland, Australia
| | - Aymeric Rouchaud
- Interventional Neuroradiology, Centre Hospitalier Universitaire de Limoges, Limoges, France
- University of Limoges, CNRS, XLIM, UMR 7252, Limoges, France
| | - Isil Saatci
- Radiology, Koru Health Group, Ankara, Turkey
| | - Adnan H Siddiqui
- Neurosurgery and Radiology, and Canon Stroke and Vascular Research Center, University at Buffalo Jacobs School of Medicine and Biomedical Sciences, Buffalo, New York, USA
- Neurosurgery, Gates Vascular Institute, Buffalo, New York, USA
| | - Laurent Spelle
- Interventional Neuroradiology, NEURI Brain Vascular Center, Biĉetre Hospital, Le Kremlin Biĉetre, France
- Paris-Saclay University Faculty of Medicine, Le Kremlin Biĉetre, France
| | - Pengfei Yang
- Department of Neurosurgery, Naval Medical University Changhai Hospital, Shanghai, China
| | - Astrid Grams
- Department of Neuroradiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Matthew J Gounis
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
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Hohenstatt S, Saatci I, Jesser J, Çekirge HS, Koçer N, Islak C, Lücking H, DuPlessis J, Rautio R, Bendszus M, Vollherbst DF, Möhlenbruch MA. Prasugrel Single Antiplatelet Therapy versus Aspirin and Clopidogrel Dual Antiplatelet Therapy for Flow Diverter Treatment for Cerebral Aneurysms: A Retrospective Multicenter Study. AJNR Am J Neuroradiol 2024; 45:592-598. [PMID: 38453414 DOI: 10.3174/ajnr.a8163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/07/2024] [Indexed: 03/09/2024]
Abstract
BACKGROUND AND PURPOSE The optimal antiplatelet regimen after flow diverter treatment of cerebral aneurysms is still a matter of debate. A single antiplatelet therapy might be advantageous in determined clinical scenarios. This study evaluated the efficacy and safety of prasugrel single antiplatelet therapy versus aspirin and clopidogrel dual antiplatelet therapy. MATERIALS AND METHODS We performed a post hoc analysis of 4 retrospective multicenter studies including ruptured and unruptured aneurysms treated with flow diversion using either prasugrel single antiplatelet therapy or dual antiplatelet therapy. Primary end points were the occurrence of any kind of procedure- or device-related thromboembolic complications and complete aneurysm occlusion at the latest radiologic follow-up (mean, 18 months). Dichotomized comparisons of outcomes were performed between single antiplatelet therapy and dual antiplatelet therapy. Additionally, the influence of various patient- and aneurysm-related variables on the occurrence of thromboembolic complications was investigated using multivariable backward logistic regression. RESULTS A total of 222 patients with 251 aneurysms were included, 90 (40.5%) in the single antiplatelet therapy and 132 (59.5%) in the dual antiplatelet therapy group. The primary outcome-procedure- or device-related thromboembolic complications-occurred in 6 patients (6.6%) of the single antiplatelet therapy and in 12 patients (9.0%) of the dual antiplatelet therapy group (P = .62; OR, 0.712; 95% CI, 0.260-1.930). The primary treatment efficacy end point was reached in 82 patients (80.4%) of the single antiplatelet therapy and in 115 patients (78.2%) of the dual antiplatelet therapy group (P = .752; OR, 1.141; 95% CI, 0.599-2.101). Logistic regression showed that non-surface-modified flow diverters (P = .014) and fusiform aneurysm morphology (P = .004) significantly increased the probability of thromboembolic complications. CONCLUSIONS Prasugrel single antiplatelet therapy after flow diverter treatment may be as safe and effective as dual antiplatelet therapy and could, therefore, be a valid alternative in selected patients. Further prospective comparative studies are required to validate our findings.
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Affiliation(s)
- Sophia Hohenstatt
- From the Department of Neuroradiology (S.H., J.J., M.B., D.F.V., M.A.M.), Heidelberg University Hospital, Heidelberg, Germany
| | - Işıl Saatci
- Interventional Neuroradiology Section (I.S., H.S.C.), Koru and Bayindir Private Hospitals, Ankara, Turkey
| | - Jessica Jesser
- From the Department of Neuroradiology (S.H., J.J., M.B., D.F.V., M.A.M.), Heidelberg University Hospital, Heidelberg, Germany
| | - H Saruhan Çekirge
- Interventional Neuroradiology Section (I.S., H.S.C.), Koru and Bayindir Private Hospitals, Ankara, Turkey
| | - Naci Koçer
- Department of Neuroradiology (N.K., CI.), Cerrahpasa Medical Faculty, Istanbul, Turkey
| | - Civan Islak
- Department of Neuroradiology (N.K., CI.), Cerrahpasa Medical Faculty, Istanbul, Turkey
| | - Hannes Lücking
- Department of Neuroradiology (H.L.), University of Erlangen-Nuremberg, Erlangen, Germany
| | - Johannes DuPlessis
- Department of Clinical Neurosciences (J.D.), Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Riitta Rautio
- Department of Interventional Radiology (R.R.), Turku University Hospital, Turku, Finland
| | - Martin Bendszus
- From the Department of Neuroradiology (S.H., J.J., M.B., D.F.V., M.A.M.), Heidelberg University Hospital, Heidelberg, Germany
| | - Dominik F Vollherbst
- From the Department of Neuroradiology (S.H., J.J., M.B., D.F.V., M.A.M.), Heidelberg University Hospital, Heidelberg, Germany
| | - Markus A Möhlenbruch
- From the Department of Neuroradiology (S.H., J.J., M.B., D.F.V., M.A.M.), Heidelberg University Hospital, Heidelberg, Germany
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Ma L, Hoz SS, Al-Bayati AR, Nogueira RG, Lang MJ, Gross BA. Flow Diverters with Surface Modification in Patients with Intracranial Aneurysms: A Systematic Review and Meta-Analysis. World Neurosurg 2024; 185:320-326.e17. [PMID: 38160909 DOI: 10.1016/j.wneu.2023.12.132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND Flow diverters with surface modification (FDSM) are increasingly being used in the treatment of intracranial aneurysms (ANs). We aimed to evaluate the effectiveness and safety across different devices and antiplatelet therapies using a systematic review and meta-analysis. METHODS A systematic review was performed to identify original studies of ≥10 patients with intracranial ANs treated with FDSM from database inception through August 2023. Primary effectiveness outcome was the rate of complete AN occlusion at follow-up ≥6 months. Safety outcomes included ischemic stroke, hemorrhage, and in-stent thrombosis, and were stratified by FDSM devices and antiplatelet therapies. Certainty of evidence was evaluated following the Grading of Recommendations, Assessment, Development, and Evaluations approach. RESULTS Twenty-seven studies were included, yielding 2161 patients with 2373 ANs. A total of 70.5% of the ANs were located on the internal carotid artery (ICA). Total 10.3% were acutely ruptured. The complete AN occlusion rate was 72.3% at follow-up ≥6 months. Sensitivity analysis in the ICA AN cohort yielded comparable occlusion rates between Pipeline Flex Embolization Device-Shield (80.4%) and Phenox-hydrophilic polymer-coated (77.5%, P = 0.54), but a lower 66.2% rate for Flow Redirection Endoluminal Device-X (P = 0.02). The rate of in-stent thrombosis and stenosis tended to be higher in Phenox-hydrophilic polymer-coated (3.4%) and Flow Redirection Endoluminal Device-X (4.3%) versus Pipeline Flex Embolization Device-Shield (0.8%, P = 0.05). CONCLUSIONS FDSM were safe with satisfactory effectiveness for intracranial ANs. More specific investigations are warranted to explore their performance in ANs beyond the ICA and optimal antiplatelet therapy.
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Affiliation(s)
- Li Ma
- Department of Neurological Surgery, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Samer S Hoz
- Department of Neurological Surgery, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Alhamza R Al-Bayati
- Department of Neurology, University of Pittsburgh Medical Center Stroke Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Raul G Nogueira
- Department of Neurology, University of Pittsburgh Medical Center Stroke Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Michael J Lang
- Department of Neurological Surgery, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Bradley A Gross
- Department of Neurological Surgery, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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Goertz L, Styczen H, Siebert E, Li Y, Schlamann M, Forsting M, Bohner G, Deuschl C, Kabbasch C. FRED X flow diverter for the treatment of intracranial aneurysms: Two-center experience and mini-review of the literature. Interv Neuroradiol 2024:15910199241246018. [PMID: 38651292 DOI: 10.1177/15910199241246018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
OBJECTIVE The flow re-direction endoluminal device (FRED) is a safe and effective treatment option for intracranial aneurysms. The novel FRED X features an antithrombotic surface coating ("X Technology") on an otherwise unmodified stent design. This two-center study evaluates the clinical safety and efficacy of FRED X and compares it to the literature. METHODS Consecutive patients treated between 2020 and 2023 were retrospectively reviewed for aneurysm characteristics, procedural details and complications, and angiographic outcomes. A mini-review of the literature for FRED X clinical trials was performed and results were pooled using a random effects model. RESULTS Thirty-four patients (mean age 56 years) were treated for 34 aneurysms. The mean aneurysm size was 7.7 ± 5.0 mm, 7 (21%) were ruptured, 6 (18%) were recurrent after previous treatment, 11 (32.3%) were located in the posterior circulation, and 4 (12.5%) had non-saccular morphology. All procedures were technically successful and no balloon angioplasty was required. There was 1 (2.9%) symptomatic complication (a transient ischemic attack) and no procedural morbidity or mortality. Technical asymptomatic events included 1 procedural stent occlusion that was reopened with thrombectomy and 3 cases of vasospasm. Complete and adequate occlusion rates were 68% (19/28) and 89% (25/28) at a mean follow-up time of 6 months, respectively. The results of this study are comparable to previous FRED X studies. CONCLUSIONS The results demonstrate a high feasibility and procedural safety of the FRED X with adequate mid-term occlusion rates. Long-term and comparative studies are needed to evaluate the full potential of the FRED X.
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Affiliation(s)
- Lukas Goertz
- Faculty of Medicine and University Hospital, Department of Radiology and Neuroradiology, University of Cologne, Cologne, Germany
| | - Hanna Styczen
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Eberhard Siebert
- Department of Neuroradiology, University Hospital Berlin (Charité), Berlin, Germany
| | - Yan Li
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Marc Schlamann
- Faculty of Medicine and University Hospital, Department of Radiology and Neuroradiology, University of Cologne, Cologne, Germany
| | - Michael Forsting
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Georg Bohner
- Department of Neuroradiology, University Hospital Berlin (Charité), Berlin, Germany
| | - Cornelius Deuschl
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Christoph Kabbasch
- Faculty of Medicine and University Hospital, Department of Radiology and Neuroradiology, University of Cologne, Cologne, Germany
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7
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Goertz L, Hohenstatt S, Vollherbst DF, Weyland CS, Nikoubashman O, Styczen H, Gronemann C, Weiss D, Kaschner M, Pflaeging M, Siebert E, Zopfs D, Kottlors J, Pennig L, Schlamann M, Bohner G, Liebig T, Turowski B, Dorn F, Deuschl C, Wiesmann M, Möhlenbruch MA, Kabbasch C. Safety and efficacy of coated flow diverters in the treatment of ruptured intracranial aneurysms: a retrospective multicenter study. J Neurointerv Surg 2024:jnis-2024-021516. [PMID: 38569886 DOI: 10.1136/jnis-2024-021516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/07/2024] [Indexed: 04/05/2024]
Abstract
BACKGROUND This multicenter study evaluated the safety and efficacy of coated flow diverters (cFDs) for the treatment of ruptured intracranial aneurysms. METHODS Consecutive patients treated with different cFDs for ruptured aneurysms under tirofiban at eight neurovascular centers between 2016 and 2023 were retrospectively analyzed. The majority of patients were loaded with dual antiplatelet therapy after the treatment. Aneurysm occlusion was determined using the O'Kelly-Marotta (OKM) grading scale. Primary outcome measures were major procedural complications and aneurysmal rebleeding during hospitalization. RESULTS The study included 60 aneurysms (posterior circulation: 28 (47%)) with a mean size of 5.8±4.7 mm. Aneurysm morphology was saccular in 28 (47%), blister-like in 12 (20%), dissecting in 13 (22%), and fusiform in 7 (12%). Technical success was 100% with a mean of 1.1 cFDs implanted per aneurysm. Adjunctive coiling was performed in 11 (18%) aneurysms. Immediate contrast retention was observed in 45 (75%) aneurysms. There was 1 (2%) major procedural complication (a major stroke, eventually leading to death) and no aneurysmal rebleeding. A good outcome (modified Rankin Scale 0-2) was achieved in 40 (67%) patients. At a mean follow-up of 6 months, 27/34 (79%) aneurysms were completely occluded (OKM D), 3/34 (9%) had an entry remnant (OKM C), and 4/34 (12%) had residual filling (OKM A or B). There was 1 (3%) severe in-stent stenosis during follow-up that was treated with balloon angioplasty. CONCLUSIONS Treatment of ruptured aneurysms with cFDs was reasonably safe and efficient and thus represents a valid treatment option, especially for complex cases.
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Affiliation(s)
- Lukas Goertz
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | - Sophia Hohenstatt
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Dominik F Vollherbst
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | | | - Omid Nikoubashman
- Department of Neuroradiology, University Hospital Aachen, Aachen, Germany
| | - Hanna Styczen
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | | | - Daniel Weiss
- Department of Neuroradiology, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Marius Kaschner
- Department of Neuroradiology, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Muriel Pflaeging
- Department of Neuroradiology, University Hospital Munich (LMU), Munich, Germany
| | - Eberhard Siebert
- Department of Neuroradiology, University Hospital Berlin (Charité), Berlin, Germany
| | - David Zopfs
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | - Jonathan Kottlors
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | - Lenhard Pennig
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | - Marc Schlamann
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | - Georg Bohner
- Department of Neuroradiology, University Hospital Berlin (Charité), Berlin, Germany
| | - Thomas Liebig
- Department of Neuroradiology, University Hospital Munich (LMU), Munich, Germany
| | - Bernd Turowski
- Department of Neuroradiology, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Franziska Dorn
- Department of Neuroradiology, University Hospital Bonn, Bonn, Germany
| | - Cornelius Deuschl
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Martin Wiesmann
- Department of Neuroradiology, University Hospital Aachen, Aachen, Germany
| | - Markus A Möhlenbruch
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Christoph Kabbasch
- Department of Radiology and Neuroradiology, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
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Yoshida S, Kazekawa K, Kamatani K, Maruyama K, Takigawa K, Tashiro N, Hashiguchi Y, Yasaka M, Aikawa H, Go Y. Prediction of obliteration of unruptured cerebral aneurysm by residual aneurysm volume after flow diverter stent treatment. World Neurosurg X 2024; 22:100354. [PMID: 38469386 PMCID: PMC10926355 DOI: 10.1016/j.wnsx.2024.100354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/21/2024] [Indexed: 03/13/2024] Open
Abstract
Introduction There is no methodology to predict aneurysm occlusion using residual volume after flow diverter stent treatment. We retrospectively examined whether residual aneurysm volume at 6 months postoperatively can predict the degree of aneurysm obliteration at 1 year after flow diverter stent treatment. Materials and Methods This single institution study included 101 consecutive patients who underwent flow diverter stent treatment for unruptured cerebral aneurysm. Based on pre-treatment aneurysm volume, the percentage residual volume was calculated 6 months postoperatively. The volume of the aneurysm was determined using the volume calculation function of the cerebral angiography equipment. 1 year postoperatively, patients were classified into two groups: the good obliteration group (GG; O'KellyMarotta [OKM] grading scale: C and D) and the poor obliteration group (PG; OKM: A and B). Statistical analysis was performed to determine if there was a difference in residual aneurysm volume percentage at 6 months postoperatively between the two groups. Results A total of 20 patients were studied: 6 in the GG and 14 in the PG. Mean residual aneurysm volume at 6 months postoperatively in the GG was 33.1% (±34.7), while that in the PG was 80.6% (±24.8) (P=0.018). A residual aneurysm volume of ≥35.2% at 6 months postoperatively was significantly associated with poor aneurysm obliteration at 1 year postoperatively (AUC=0.88, P=0.008). Conclusions Residual aneurysm volume percentage at 6 months after flow diverter stent treatment might be able to predict the likelihood of aneurysm occlusion at 1 year postoperatively.
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Affiliation(s)
- Shinichiro Yoshida
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Kiyoshi Kazekawa
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Kaisei Kamatani
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Kousei Maruyama
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Kousuke Takigawa
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Noriaki Tashiro
- Depatment of Cerebrovascular Medicine, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Yoshiya Hashiguchi
- Depatment of Cerebrovascular Medicine, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Masahiro Yasaka
- Depatment of Cerebrovascular Medicine, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Hiroshi Aikawa
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
| | - Yoshinori Go
- Department of Neurosurgery, Fukuoka Neurosurgical Hospital, 5-3-1 Osa, Minamiku, Fukuoka, 811-1313, Japan
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Guimaraens L, Saldaña J, Vivas E, Cifuentes S, Balaguer E, Mon D, Macias-Gómez A, Ois A, Guisado-Alonso D, Cuadrado-Godia E, Jiménez-Balado J. Flow diverter stents for endovascular treatment of aneurysms: a comparative study of efficacy and safety between FREDX and FRED. J Neurointerv Surg 2024:jnis-2023-021103. [PMID: 38228386 DOI: 10.1136/jnis-2023-021103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 12/22/2023] [Indexed: 01/18/2024]
Abstract
BACKGROUND The FRED X flow diverter (FREDX), as the second generation in the FRED series, aims to improve the treatment of cerebral aneurysms. This study compares the efficacy and safety of FREDX with its predecessor, FRED. METHODS This prospective registry included patients treated with FRED and FREDX devices. Efficacy was assessed using digital subtraction angiography with 3D volumetric reconstruction at immediate and 1 year follow-ups. Safety was evaluated by recording complications, analyzed through univariate contrasts, generalized mixed models, and Bayesian network analyses. RESULTS We treated 287 patients with 385 aneurysms, with 77.9% receiving FRED and 22.1% FREDX. The median age was 55 years (IQR 47-65) and 78.4% were women. The FREDX group showed a higher prevalence of saccular-like aneurysms (70.6% vs 52.7%, P=0.012) and a higher rate of complete occlusion compared with FRED interventions (79.4% vs 59.3%, P=0.022). After adjusting for confounders, these differences represented a 3.04-fold increased likelihood (95% CI 1.44 to 6.41, P=0.003) of achieving complete occlusion at 1 year with FREDX interventions. Regarding safety, two (3.5%) complications (both non-symptomatic) were observed in the FREDX group and 23 (10.4%) in the FRED group (P=0.166). Bayesian network analysis suggested a trend towards fewer complications for FREDX, with a median reduction of 5.5% in the posterior distribution of the prevalence of complications compared with FRED interventions. CONCLUSIONS The FREDX device shows improved complete occlusion rates at 1 year compared with the FRED device while maintaining a favourable safety profile, indicating its potential advantage in the treatment of cerebral aneurysms.
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Affiliation(s)
- Leopoldo Guimaraens
- J.J. Merland Department of Therapeutic Neuroangiography, Hospital del Mar and Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Jesus Saldaña
- J.J. Merland Department of Therapeutic Neuroangiography, Hospital del Mar and Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Elio Vivas
- J.J. Merland Department of Therapeutic Neuroangiography, Hospital del Mar and Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Sebastián Cifuentes
- J.J. Merland Department of Therapeutic Neuroangiography, Hospital del Mar and Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Ernest Balaguer
- Department of Neurology, Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Dunia Mon
- Department of Neurology, Hospital Universitari General de Catalunya, Barcelona, Spain
| | - Adrià Macias-Gómez
- Department of Neurology, Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Angel Ois
- Department of Neurology, Hospital del Mar Medical Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
| | - Daniel Guisado-Alonso
- Department of Neurology, Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Elisa Cuadrado-Godia
- Department of Neurology, Hospital del Mar Medical Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
| | - Joan Jiménez-Balado
- Department of Neurology, Hospital del Mar Medical Research Institute, Barcelona, Spain
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White TG, Santhumayor BA, Turpin J, Shah K, Toscano D, Teron I, Link T, Patsalides A, Woo HH. Flow diverter surface modifications for aneurysm treatment: A review of the mechanisms and data behind existing technologies. Interv Neuroradiol 2023:15910199231207550. [PMID: 37899636 DOI: 10.1177/15910199231207550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023] Open
Abstract
Flow diversion (FD) has become a mainstay treatment for large wide-necked aneurysms. Despite excellent safety and efficacy, the risk of thromboembolic complications necessitates the use of dual antiplatelet therapy (DAPT). The use of DAPT makes hemorrhagic complications of stenting carry high morbidity and mortality. Additionally, DAPT usage carries a risk of "nuisance" complications that do not directly impact intracranial circulation but need to be managed nonetheless. To circumvent this issue, the most recent generation of flow diverters have undergone surface modification with various compounds to confer blood compatibility to limit clotting and thrombosis. While these newer generation flow diverters are marketed to enhance ease of deployment, the goal is to eventually facilitate single antiplatelet use with flow diverter treatment. This generation of FDs have potential to expand indications beyond unruptured wide-necked aneurysms to include ruptured intracranial aneurysms without the necessity of DAPT. Currently, no comprehensive review details the molecular mechanisms and pre-clinical and clinical data on these modifications. We seek to fill this gap in the literature by consolidating information on the coating technology for four major FDs currently in clinical use-PipelineTM Flex and Vantage Shield TechnologyTM, FREDTMX, p48/64 hydrophilic coating, and Acandis Dervio® 2heal-to serve as a reference guide in neurointerventional aneurysm treatment. Although the Balt silkTM was one of the first FDs, it is uncoated, thus we will not cover this device in our review. A literature review was performed to obtain information on each coating technology for the major flow diverters currently on the market using international databases (PUBMED, Embase, Medline, Google Scholar). The search criteria used the keywords for each coating technology of interest "phosphorylcholine," "poly 2-methoxyethyl acrylate," "hydrophilic polymer coating," and "fibrin-heparin" Keywords related to the device names "Pipeline Shield," "Pipeline Shield with Flex Technology," "FRED," "FREDX," "p64," "p64-HPC," "Derivo 2heal" were also used. Studies that detailed the mechanism of action of the coating, any pre-clinical studies with surface-modified intravascular devices, and any clinical retrospective series, prospective series, or randomized clinical trials with surface-modified devices for aneurysm treatment were included.
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Affiliation(s)
- Timothy G White
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Brandon A Santhumayor
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Justin Turpin
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Kevin Shah
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Daniel Toscano
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Ina Teron
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Thomas Link
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Athos Patsalides
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
| | - Henry H Woo
- Department of Neurosurgery, North Shore University Hospital, Donald and Barbara Zucker School of Medicine, Manhasset, NY, USA
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Zoppo CT, Mocco J, Manning NW, Bogdanov AA, Gounis MJ. Surface modification of neurovascular stents: from bench to patient. J Neurointerv Surg 2023:jnis-2023-020620. [PMID: 37793794 DOI: 10.1136/jnis-2023-020620] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 09/19/2023] [Indexed: 10/06/2023]
Abstract
Flow-diverting stents (FDs) for the treatment of cerebrovascular aneurysms are revolutionary. However, these devices require systemic dual antiplatelet therapy (DAPT) to reduce thromboembolic complications. Given the risk of ischemic complications as well as morbidity and contraindications associated with DAPT, demonstrating safety and efficacy for FDs either without DAPT or reducing the duration of DAPT is a priority. The former may be achieved by surface modifications that decrease device thrombogenicity, and the latter by using coatings that expedite endothelial growth. Biomimetics, commonly achieved by grafting hydrophilic and non-interacting polymers to surfaces, can mask the device surface with nature-derived coatings from circulating factors that normally activate coagulation and inflammation. One strategy is to mimic the surfaces of innocuous circulatory system components. Phosphorylcholine and glycan coatings are naturally inspired and present on the surface of all eukaryotic cell membranes. Another strategy involves linking synthetic biocompatible polymer brushes to the surface of a device that disrupts normal interaction with circulating proteins and cells. Finally, drug immobilization can also impart antithrombotic effects that counteract normal foreign body reactions in the circulatory system without systemic effects. Heparin coatings have been explored since the 1960s and used on a variety of blood contacting surfaces. This concept is now being explored for neurovascular devices. Coatings that improve endothelialization are not as clinically mature as anti-thrombogenic coatings. Coronary stents have used an anti-CD34 antibody coating to capture circulating endothelial progenitor cells on the surface, potentially accelerating endothelial integration. Similarly, coatings with CD31 analogs are being explored for neurovascular implants.
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Affiliation(s)
- Christopher T Zoppo
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - J Mocco
- Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nathan W Manning
- The MIRI Centre, Ingham Institute for Applied Medical Science, Sydney, New South Wales, Australia
- Department of Interventional Radiology, Liverpool Hospital, Sydney, New South Wales, Australia
| | - Alexei A Bogdanov
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Matthew J Gounis
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
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Goertz L, Zopfs D, Schönfeld M, Zaeske C, Pennig L, Brinker G, Schlamann M, Kabbasch C. First clinical experience with the Derivo 2heal embolization device for the treatment of intracranial aneurysms. Interv Neuroradiol 2023:15910199231193577. [PMID: 37574801 DOI: 10.1177/15910199231193577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023] Open
Abstract
OBJECTIVE The development of new flow-diverting devices with antithrombotic coatings may result in an improved safety profile, particularly a reduction in ischaemic stroke rates. The aim of this study was to evaluate our initial experience with the recently introduced coated Derivo® 2heal® Embolization Device (Acandis, Pforzheim, Germany). METHODS This is a retrospective, single-centre analysis of patients with intracranial aneurysms undergoing Derivo® 2heal® Embolization Device treatment. Patient and aneurysm characteristics, procedural parameters, complications, and degree of initial and short-term aneurysm occlusion were evaluated on an intention-to-treat basis. RESULTS A total of 16 unruptured aneurysms in 9 patients were treated with the Derivo® 2heal® Embolization Device in 10 treatment sessions. In one case the Derivo® 2heal® Embolization Device could not be deployed due to severe friction in the microcatheter. In all successful cases, one Derivo® 2heal® Embolization Device was sufficient to treat the target aneurysm and no additional coiling was performed. In-stent balloon angioplasty was performed in one procedure (10%) to improve vessel wall apposition. Twelve arterial side branches were covered in 9 procedures and all were patent at the end of the procedure. There were no clinical complications and no thromboembolic events during treatment. At the end of the procedure, contrast retention was observed in 13/16 (81%) aneurysms and at short-term follow-up, 6/9 (67%) were completely occluded. CONCLUSIONS The preliminary results of the new Derivo® 2heal® Embolization Device appear promising and warrant further evaluation by multicentre studies with long-term follow-up.
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Affiliation(s)
- Lukas Goertz
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - David Zopfs
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Michael Schönfeld
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Charlotte Zaeske
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Lenhard Pennig
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Gerrit Brinker
- Faculty of Medicine and University Hospital, Center for Neurosurgery, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Marc Schlamann
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
| | - Christoph Kabbasch
- Department of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Kerpener Strasse 62, Cologne, Germany
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