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Zheng Y, Zheng L, Sun Y, Lin D, Wang B, Sun Q, Bian L. Surgical Clipping of Previously Coiled Recurrent Intracranial Aneurysms: A Single-Center Experience. Front Neurol 2021; 12:680375. [PMID: 34621232 PMCID: PMC8490643 DOI: 10.3389/fneur.2021.680375] [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: 03/14/2021] [Accepted: 08/12/2021] [Indexed: 11/17/2022] Open
Abstract
Objective: This study reviews our experiences in surgical clipping of previously coiled aneurysms, emphasizing on recurrence mechanism of intracranial aneurysms (IAs) and surgical techniques for different types of recurrent IAs. Method: We performed a retrospective study on 12 patients who underwent surgical clipping of aneurysms following endovascular treatment between January 2010 and October 2020. The indications for surgery, surgical techniques, and clinical outcomes were analyzed. Result: Twelve patients with previously coiled IAs were treated with clipping in this study, including nine females and three males. The reasons for the patients having clipping were as follows: early surgery (treatment failure in two patients, postoperative early rebleeding in one patient, and intraprocedural aneurysm rupture during embolization in one patient) and late surgery (aneurysm recurrence in five patients, SAH in one, mass effect in one, and aneurysm regrowth in one). All aneurysms were clipped directly, and coil removal was performed in four patients. One patient died (surgical mortality, 8.3%), 1 patient (8.3%) experienced permanent neurological morbidity, and the remaining 10 patients (83.4%) had good outcomes. Based on our clinical data and previous studies, we classified the recurrence mechanism of IAs into coil compaction, regrowth, coil migration, and coil loosening. Then, we elaborated the specific surgical planning and timing of surgery depending on the recurrence type of IAs. Conclusion: Surgical clipping can be a safe and effective treatment strategy for the management of recurrent coiled IAs, with acceptable morbidity and mortality in properly selected cases. Our classification of recurrent coiled aneurysms into four types helps to assess the optimal surgical approach and the associated risks in managing them.
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Affiliation(s)
- Yongtao Zheng
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Lili Zheng
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yuhao Sun
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Dong Lin
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Baofeng Wang
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qingfang Sun
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Liuguan Bian
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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Poupart O, Conti R, Schmocker A, Pancaldi L, Moser C, Nuss KM, Sakar MS, Dobrocky T, Grützmacher H, Mosimann PJ, Pioletti DP. Pulsatile Flow-Induced Fatigue-Resistant Photopolymerizable Hydrogels for the Treatment of Intracranial Aneurysms. Front Bioeng Biotechnol 2021; 8:619858. [PMID: 33553124 PMCID: PMC7855579 DOI: 10.3389/fbioe.2020.619858] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/22/2020] [Indexed: 11/13/2022] Open
Abstract
An alternative intracranial aneurysm embolic agent is emerging in the form of hydrogels due to their ability to be injected in liquid phase and solidify in situ. Hydrogels have the ability to fill an aneurysm sac more completely compared to solid implants such as those used in coil embolization. Recently, the feasibility to implement photopolymerizable poly(ethylene glycol) dimethacrylate (PEGDMA) hydrogels in vitro has been demonstrated for aneurysm application. Nonetheless, the physical and mechanical properties of such hydrogels require further characterization to evaluate their long-term integrity and stability to avoid implant compaction and aneurysm recurrence over time. To that end, molecular weight and polymer content of the hydrogels were tuned to match the elastic modulus and compliance of aneurysmal tissue while minimizing the swelling volume and pressure. The hydrogel precursor was injected and photopolymerized in an in vitro aneurysm model, designed by casting polydimethylsiloxane (PDMS) around 3D printed water-soluble sacrificial molds. The hydrogels were then exposed to a fatigue test under physiological pulsatile flow, inducing a combination of circumferential and shear stresses. The hydrogels withstood 5.5 million cycles and no significant weight loss of the implant was observed nor did the polymerized hydrogel protrude or migrate into the parent artery. Slight surface erosion defects of 2–10 μm in depth were observed after loading compared to 2 μm maximum for non-loaded hydrogels. These results show that our fine-tuned photopolymerized hydrogel is expected to withstand the physiological conditions of an in vivo implant study.
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Affiliation(s)
- Oriane Poupart
- Laboratory of Biomechanical Orthopedics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Riccardo Conti
- Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Andreas Schmocker
- Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, Zurich, Switzerland.,Laboratory of Applied Photonics Devices, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, Bern, Switzerland
| | - Lucio Pancaldi
- Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Christophe Moser
- Laboratory of Applied Photonics Devices, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Katja M Nuss
- Musculoskeletal Research Unit, Department of Molecular Mechanisms of Disease, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Mahmut S Sakar
- Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Tomas Dobrocky
- Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, Bern, Switzerland
| | - Hansjörg Grützmacher
- Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Pascal J Mosimann
- Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, Bern, Switzerland.,Department of Diagnostic and Interventional Neuroradiology, Alfried Krupp Hospital, Essen, Germany
| | - Dominique P Pioletti
- Laboratory of Biomechanical Orthopedics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Liu W, Dai D, Ding YH, Liu Y, Temnyk K, Shen TW, Cardinal KO, Kallmes DF, Kadirvel R. Cellular responses to flow diverters in a tissue-engineered aneurysm model. J Neurointerv Surg 2020; 13:746-751. [PMID: 33158994 DOI: 10.1136/neurintsurg-2020-016593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Notwithstanding the widespread implementation of flow diverters (FDs) in the treatment of intracranial aneurysms, the exact mechanism of action of these devices remains elusive. We aimed to advance the understanding of cellular responses to FD implantation using a 3D tissue-engineered in vitro aneurysm model. METHODS Aneurysm-like blood vessel mimics (aBVMs) were constructed by electrospinning polycaprolactone nanofibers onto desired aneurysm-like geometries. aBVMs were seeded with human aortic smooth muscle cells (SMCs) followed by human aortic endothelial cells (ECs). FDs were then deployed in the parent vessel of aBVMs covering the aneurysm neck and were cultivated for 7, 14, or 28 days (n=3 for each time point). The EC and SMC coverage in the neck was measured semi-quantitatively. RESULTS At day 7, the device segment in contact with the parent vessel was partially endothelialized. Also, the majority of device struts, but not pores, at the parent vessel and neck interface were partially covered with ECs and SMCs, while device struts in the middle of the neck lacked cell coverage. At 14 days, histology verified a neointimal-like lining had formed, partially covering both the struts and pores in the center of the neck. At 28 days, the majority of the neck was covered with a translucent neointimal-like layer. A higher degree of cellular coverage was seen on the struts and pores at the neck at 28 days compared with both 7 and 14 days. CONCLUSION aBVMs can be a valuable alternative tool for evaluating the healing mechanisms of endovascular aneurysm devices.
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Affiliation(s)
- Wenjing Liu
- Radiology, Mayo Clinic, Rochester, Minnesota, USA.,Geriatrics, China Medical University First Hospital, Shenyang, China
| | - Daying Dai
- Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Yang Liu
- Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Kristen Temnyk
- Biomedical Engineering Department, Cal Poly, San Luis Obispo, California, USA
| | - Tiffany W Shen
- Biomedical Engineering Department, Cal Poly, San Luis Obispo, California, USA
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Kolumam Parameswaran P, Dai D, Ding YH, Gunderson T, Kallmes DF, Kadirvel R. Assessment of endothelialization of aneurysm wall over time in a rabbit model through CD31 scoring. J Neurointerv Surg 2017; 10:888-891. [PMID: 29288193 DOI: 10.1136/neurintsurg-2017-013381] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/30/2017] [Accepted: 12/01/2017] [Indexed: 01/27/2023]
Abstract
BACKGROUND Intracranial aneurysms represent a significant health concern and are poorly understood despite decades of research. Our study focused on understanding temporal patterns of endothelial cell distribution in different spatial locations within the aneurysm early after creation in a rabbit model. METHODS Elastase induced saccular aneurysms were created in rabbits and harvested on day 1 (n=3) and after 2 (n=5), 4 (n=4), 8 (n=5), and 12 (n=6) weeks. Sham operated controls (n=3) were harvested on the same day. Aneurysm and control tissue samples were subjected to en face whole mount CD31 staining for endothelial cells. Semiquantitative scoring was performed on the basis of endothelial coverage of the vessel wall (proximal, middle, and distal portions of the aneurysm dome). Mixed effects models were used to assess the effect of time and aneurysm section on endothelial coverage. RESULTS Aneurysmal segments were near completely de-endothelialized at 4 and 8 weeks but had re-endothelialized by 12 weeks. Compared with controls, aneurysms at all time points showed decreased endothelialization, but the difference was only significant compared with the 4 and 8 week groups. Both time (P=0.03) and aneurysm section (P=0.07) were significantly associated with the degree of endothelialization. Proximal locations showed increased endothelialization compared with distal locations (P=0.03). CONCLUSION In experimental aneurysms of rabbits, endothelial cells regress during the first month after creation, followed by ascending re-endothelialization that stays incomplete. These findings suggest that re-population of endothelial cells comes from resident cells in the adjacent parent artery and that deranged hemodynamics may affect full reconstitution of endothelial cells long term.
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Affiliation(s)
| | - Daying Dai
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Yong-Hong Ding
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Tina Gunderson
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA
| | - David F Kallmes
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
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Nakazaki M, Nonaka T, Nomura T, Onda T, Yonemasu Y, Takahashi A, Hashimoto Y, Honda O, Oka S, Sasaki M, Daibo M, Honmou O. Cerebral aneurysm neck diameter is an independent predictor of progressive occlusion after stent-assisted coiling. Acta Neurochir (Wien) 2017; 159:1313-1319. [PMID: 28488070 DOI: 10.1007/s00701-017-3199-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 04/24/2017] [Indexed: 11/26/2022]
Abstract
BACKGROUND Some intracranial aneurysms treated by stent-assisted coiling (SAC) with incomplete occlusion undergo progressive occlusion (PO) during follow-up period. We analyzed the predictors for the occurrence of PO. METHODS Among 74 cerebral aneurysms treated by SAC using the Enterprise or Neuroform stents from 2010 to 2015, we included 43 aneurysms with occlusion grade of neck remnant (NR, n = 36) or residual aneurysm (RA, n = 7) at the post-procedure. We defined PO as improvement in occlusion grade from RA to NR, or from NR or RA to complete occlusion on angiographic follow-up imaging at 6 months after the procedure. We analyzed the independent predictors for PO using a multivariate logistic regression model and receiver operating characteristic (ROC) curve analysis. RESULTS Forty-three aneurysms were analyzed, with mean volume embolization ratio of 30.3 ± 6.7%. Twenty aneurysms (47%) achieved PO. Univariate analysis found that the median neck diameter of the aneurysms was smaller in aneurysms with PO than others. Multivariate logistic regression analysis also found that the odds ratio of neck diameter of the aneurysm for PO was 0.44 (95% CI, 0.19-0.82, p < 0.01). Moreover, ROC curve analysis for PO found that the optimal cut-off value of the neck diameter was 5.5 mm, with a sensitivity of 95%, specificity of 57% (p < 0.01). CONCLUSIONS Incompletely occluded aneurysms with a neck diameter of 5.5 mm or less might be more likely to develop PO within 6 months after SAC by using Enterprise or Neuroform stents.
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Affiliation(s)
- Masahito Nakazaki
- Department of Neural Regenerative Medicine, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, 060-8556, Japan.
| | - Tadashi Nonaka
- Department of Neuroendovascular Therapy, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Tatsufumi Nomura
- Department of Neuroendovascular Therapy, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Toshiyuki Onda
- Department of Neuroendovascular Therapy, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Yasuyuki Yonemasu
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Akira Takahashi
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Yuji Hashimoto
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Osamu Honda
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Shinichi Oka
- Department of Neural Regenerative Medicine, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, 060-8556, Japan
| | - Masanori Sasaki
- Department of Neural Regenerative Medicine, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, 060-8556, Japan
| | - Masahiko Daibo
- Department of Neurosurgery, Sapporo Shiroishi Memorial Hospital, Sapporo, Hokkaido, 003-0026, Japan
| | - Osamu Honmou
- Department of Neural Regenerative Medicine, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, 060-8556, Japan
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Brinjikji W, Amar AP, Delgado Almandoz JE, Diaz O, Jabbour P, Hanel R, Hui F, Kelly M, Layton KD, Miller JW, Levy E, Moran C, Suh DC, Woo H, Sellar R, Ho B, Evans A, Kallmes DF. GEL THE NEC: a prospective registry evaluating the safety, ease of use, and efficacy of the HydroSoft coil as a finishing device. J Neurointerv Surg 2017; 10:83-87. [DOI: 10.1136/neurintsurg-2016-012915] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/05/2017] [Accepted: 01/10/2017] [Indexed: 11/03/2022]
Abstract
Background and purposeThe HydroSoft coil was developed as a finishing coil, ideally to be placed along the aneurysm neck to enhance intracranial aneurysm healing. The GEL THE NEC (Gaining Efficacy Long Term: Hydrosoft, an Emerging, New, Embolic Coil) multicenter registry was developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We report angiographic and clinical results of this prospective registry.Materials and methodsGEL THE NEC was performed at 27 centers in five countries. Patients aged 21–90 years with a ruptured or unruptured aneurysm 3–15 mm in size were eligible for enrollment. The following variables were obtained: demographics/comorbidities, aneurysm geometry, adjunctive devices used, proportion of patients in whom HydroSoft coils were successfully placed, and long-term angiographic outcomes (graded by an independent core laboratory using the Modified Raymond Scale), and procedure-related adverse events. Predictors of good angiographic outcome were studied using χ2 and t-tests.ResultsA total of 599 patients with 599 aneurysms were included in this study. HydroSoft coils were successfully deployed in 577 (96.4%) patients. Procedure-related major morbidity and mortality were 0.5% (3/599) and 1.3% (8/599), respectively. The most common perioperative complications were iatrogenic vasospasm (30/599, 5.0%), thromboemboli (27/599, 4.5%), and aneurysm perforation (16/599, 2.7%). At last angiographic follow-up (mean 9.0±6.3 months), the complete occlusion rate was 63.2% (280/442) and near complete occlusion rate was 25.2% (107/442). The core laboratory read recanalization rate was 10.8% (46/425) and the retreatment rate was 3.4% (20/599).ConclusionsEndovascular treatment of intracranial aneurysms with HydroSoft coils resulted in complete/near complete occlusion rates of 88% and a major complication rate of 1.8%.Trial registration numberNCT01000675.
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Rouchaud A, Brinjikji W, Dai D, Ding YH, Gunderson T, Schroeder D, Spelle L, Kallmes DF, Kadirvel R. Autologous adipose-derived mesenchymal stem cells improve healing of coiled experimental saccular aneurysms: an angiographic and histopathological study. J Neurointerv Surg 2017; 10:60-65. [PMID: 28077523 DOI: 10.1136/neurintsurg-2016-012867] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 01/06/2023]
Abstract
PURPOSE Long-term occlusion of coiled aneurysms frequently fails, probably because of poor intrasaccular healing and inadequate endothelialization across the aneurysm neck. The purpose of this study was to determine if attachment of autologous mesenchymal stem cells (MSCs) to platinum coils would improve the healing response in an elastase-induced aneurysm model in rabbits. MATERIALS AND METHODS With approval from the institutional animal care and use committee, aneurysms were created in rabbits and embolized with control platinum coils (Axium; Medtronic) (n=6) or coils seeded ex vivo with autologous adipose-tissue MSCs (n=7). Aneurysmal occlusion after embolization was evaluated at 1 month with angiography. Histological samples were analyzed by gross imaging and graded on the basis of neck and dome healing on H&E staining. Fibrosis was evaluated using a ratio of the total area presenting collagen. Endothelialization of the neck was quantitatively analyzed using CD31 immunohistochemistry. χ2 and Student's t-test were used to compare groups. RESULTS Healing score (11.5 vs 8.0, p=0.019), fibrosis ratio (10.3 vs 0.13, p=0.006) and endothelialization (902 262 μm2 vs 31 810 μm2, p=0.041) were significantly greater in the MSC group. The MSC group showed marked cellular proliferation and thrombus organization, with a continuous membrane bridging the neck of the aneurysm. Angiographic stable or progressive occlusion rate was significantly lower in the MSC group (0.00, 95% CI 0.00 to 0.41) compared with controls (0.67, 95% CI 0.22 to 0.96) (p=0.02). CONCLUSIONS Autologous MSCs attached to platinum coils significantly improve histological healing, as they result in improved neck endothelialization and collagen matrix formation within the aneurysm sac.
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Affiliation(s)
- Aymeric Rouchaud
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA.,Department of Interventional Neuroradiology, NEURI Center, Le Kremlin-Bicetre, France
| | | | - Daying Dai
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Yong-Hong Ding
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Tina Gunderson
- Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, USA
| | - Dana Schroeder
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Laurent Spelle
- Department of Interventional Neuroradiology, NEURI Center, Le Kremlin-Bicetre, France
| | - David F Kallmes
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
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Cekirge HS, Saatci I. A New Aneurysm Occlusion Classification after the Impact of Flow Modification. AJNR Am J Neuroradiol 2015; 37:19-24. [PMID: 26316566 DOI: 10.3174/ajnr.a4489] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/08/2015] [Indexed: 11/07/2022]
Abstract
A new classification is proposed for cerebral aneurysms treated with any endovascular technique, for example, coiling with or without adjunctive devices, flow diversion, intrasaccular flow modifiers, or any combination of the above. Raymond-Roy Occlusion Classification is expanded with novel subgroups such as class 1 represents complete occlusion and is subdivided if a branch is integrated to, or originated from, the aneurysm sac; class 2 represents neck filling; class 3 represents incomplete occlusion with aneurysm filling as in the previous classification; and class 4 describes the immediate postoperative status after extra- or intrasaccular flow modification treatment. A new concept, "stable remodeling," is included as class 5, which represents filling in the neck region that stays unchanged or reduced, as shown with at least 2 consecutive control angiographies, at least 6 months apart, for not <1 year, or the remodeled appearance of a dilated and/or tortuous vessel in continuation with the parent artery without sac filling.
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Affiliation(s)
- H S Cekirge
- From the Department of Radiology (H.S.C), Bayindir Hospital, Ankara, Turkey
| | - I Saatci
- Department of Radiology (I.S.), Yüksek Ihtisas University, Koru Hospital, Ankara, Turkey.
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