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Fan Y, Lei J, Fei F, Liu J, Liu Y. A novel flow diverter device (Tubridge) for the treatment of intracranial aneurysms: a systematic review and meta-analysis. Neurosurg Rev 2023; 46:198. [PMID: 37561213 DOI: 10.1007/s10143-023-02100-6] [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: 06/05/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 08/11/2023]
Abstract
The flow diverter (FD) device has become a feasible and effective option for treating intracranial aneurysms. This study aimed to evaluate the efficacy and safety of Tubridge FD (TFD) in treating intracranial aneurysms and provide evidence for further research and clinical application. Electronic databases, including PubMed, Web of Science, Embase, and the Cochrane Library from inception to July 31, 2022, were searched. The eligible studies should include TFD investigations in treating intracranial aneurysms. Pooled technical success rate, complete occlusion rate, improvement rate, stable rate, symptom elimination rate, and adverse events rate were calculated with either the fixed-effects model or the random-effects model, depending on the results of tests for heterogeneity. Egger's tests were performed to assess the potential publication bias. A total of 7 studies (145 patients) were included in this study. The pooled technical success rate was 0.98, the complete occlusion rate was 0.79, the improvement rate was 0.21, and the stable rate was 0.05. One included study reported that the surgery-related mortality rate in the Tubridge group was higher than that in the control group (3.66% vs. 1.61%), while the surgery-related morbidity rate in the Tubridge group was 2.4% and that in the control group was 0. Findings of this meta-analysis indicate that TFD manifests promising and effective performance with acceptable adverse events in the treatment of intracranial aneurysms.
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Affiliation(s)
- Yingjun Fan
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jun Lei
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Fan Fei
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jun Liu
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yanhui Liu
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, 610041, China.
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Tong X, Han M, Wu Z, Feng X, Liu A. Effects of different stent size selection on pipeline embolization device treatment of intracranial aneurysms. Ther Adv Neurol Disord 2023; 16:17562864231151475. [PMID: 36776531 PMCID: PMC9909058 DOI: 10.1177/17562864231151475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 12/29/2022] [Indexed: 02/09/2023] Open
Abstract
Background Pipeline embolization device (PED) is becoming increasingly common in therapeutic practice. In idealized model studies, treatment effectiveness may vary with different stent sizes in the same vasculature. The true effect of stent size selection in the clinical setting remains unknown, however. Objective To determine the true effect of stent size selection in the clinical setting. Design It is a retrospective review. Methods A retrospective review was conducted on consecutive patients with aneurysms treated with a PED at our institution. The primary exposures were the difference between the diameter of the stent and the parent artery (DD) and the difference between the length of the stent and the aneurysm neck (DL). The outcomes were the clinical and angiographic results, perioperative complications, balloon application, and in-stent stenosis. The results were generated using univariable and multivariable logistic regression and restricted cubic spline (RCS) curves. Results A larger DD was significantly associated with incomplete occlusion [odds ratio (OR) = 2.37; 95% confidence interval (CI) = 1.43-3.98; p < 0.001], while a larger DL was significantly associated with balloon application (OR = 1.12; 95% CI = 1.02-1.23; p = 0.021) and in-stent stenosis (>25%) (OR = 1.07; 95% CI = 1.01-1.16; p = 0.042). The RCS curve indicated that the risk of incomplete occlusion increased as the DD became larger, the possibility of balloon application increased as the DL increased when the DL was >5.7 mm, and the risk of in-stent stenosis (>25%) increased as the DL increased. Conclusion In the clinical setting, stent selection was associated with treatment effectiveness and may add to the treatment burden. These occurrences should be considered for aneurysms treated with PED.
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Affiliation(s)
| | | | - Zhongxue Wu
- Neurointerventional Center, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital University, Beijing, China
| | - Xin Feng
- Neurosurgery Center, Department of Cerebrovascular Surgery, Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China,Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Guangzhou, China
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Pravdivtseva MS, Pravdivtsev AN, Peters S, Hensler J, Larsen N, Hövener JB, Jansen O, Wodarg F. The effect of the size of the new contour neurovascular device for altering intraaneurysmal flow. Interv Neuroradiol 2023:15910199221145985. [PMID: 36594503 DOI: 10.1177/15910199221145985] [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: 01/04/2023] Open
Abstract
BACKGROUND Recently, a novel intrasaccular device (contour neurovascular system, contour) was introduced to treat intracranial aneurysms. Contour is placed at thе aneurysm neck and reduces the intraaneurysmal blood inflow. Contour comes in a range of sizes to target different aneurysms. The efficiency of altering flow with contour and the effect of device size have not yet been investigated. Therefore, we studied the effect of the device size with patient-based aneurysm models using 2D digital subtraction angiography (DSA). METHODS Three patient-based aneurysm models with necks ranging from 2.7 to 9.7 mm were produced, providing standardized testing conditions. Contours with diameters of 5, 11, and 14 mm were implanted into the models, four of each size. 2D DSA images were acquired before and after implanting contour (15 frames/s, manual contrast injection). After injecting angiographic contrast agent, the DSA signal was recorded over time to calculate the contrast washout time (WOT), which is a measure of flow diversion efficiency. RESULTS All contour devices caused contrast agent stasis and increased WOT in aneurysm sac (p-value = 0.0005). The median relative WOT was largest for 5-mm contour (6.6 ± 3.2) and similar for 11-mm contour (3.4 ± 2.6) and 14-mm contour (3.2 ± 3.8). The implantation procedure might affect WOT values even for contours of the same size; the overall relative WOT ranged between 1.5 and 10.89. CONCLUSION The 5-mm contour showed the longest WOT value in our study, while no apparent difference between 11-mm contour and 14-mm contour was found.
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Affiliation(s)
- Mariya S Pravdivtseva
- Department of Radiology and Neuroradiology, Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), 54186University Medical Center Schleswig-Holstein (UKSH), Kiel University, Kiel, Germany
| | - Andrey N Pravdivtsev
- Department of Radiology and Neuroradiology, Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), 54186University Medical Center Schleswig-Holstein (UKSH), Kiel University, Kiel, Germany
| | - Sönke Peters
- Department of Radiology and Neuroradiology, 9179University Medical Center Schleswig-Holstein (UKSH), Kiel, Germany
| | - Johannes Hensler
- Department of Radiology and Neuroradiology, 9179University Medical Center Schleswig-Holstein (UKSH), Kiel, Germany
| | - Naomi Larsen
- Department of Radiology and Neuroradiology, 9179University Medical Center Schleswig-Holstein (UKSH), Kiel, Germany
| | - Jan-Bernd Hövener
- Department of Radiology and Neuroradiology, Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), 54186University Medical Center Schleswig-Holstein (UKSH), Kiel University, Kiel, Germany
| | - Olav Jansen
- Department of Radiology and Neuroradiology, 9179University Medical Center Schleswig-Holstein (UKSH), Kiel, Germany
| | - Fritz Wodarg
- Department of Radiology and Neuroradiology, 9179University Medical Center Schleswig-Holstein (UKSH), Kiel, Germany
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Tang H, Lu Z, Xue G, Li S, Xu F, Yan Y, Liu J, Zuo Q, Luo Y, Huang Q. The development and understanding of intracranial aneurysm based on rabbit model. Neuroradiology 2020; 62:1219-1230. [PMID: 32594185 DOI: 10.1007/s00234-020-02475-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/10/2020] [Indexed: 10/24/2022]
Abstract
In modern society, intracranial aneurysms have seriously affected people's life. To better study and treat intracranial aneurysm, animal models are ideal candidates to perform biological research and preclinical endovascular device testing. Rabbit aneurysm model is one of the most commonly used animal models, and the rabbit aneurysms share similarities in histology, morphology, and hemodynamic aspects with human intracranial aneurysms, which is an ideal model for intracranial aneurysm pre-clinical and basic research. In this review, we will summarize the main methods of establishing rabbit aneurysms model and will further discuss the current biological mechanisms of intracranial aneurysms based on rabbit model. Further improvements of rabbit aneurysm model and more deep studies based on this model are needed to provide new insights into studying and clinical treating intracranial aneurysm.
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Affiliation(s)
- Haishuang Tang
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China.,Naval Medical Center of PLA, Second Military Medical University, Shanghai, 200050, People's Republic of China
| | - Zhiwen Lu
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Gaici Xue
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Sisi Li
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Fengfeng Xu
- Naval Medical Center of PLA, Second Military Medical University, Shanghai, 200050, People's Republic of China
| | - Yazhou Yan
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Jianmin Liu
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Qiao Zuo
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Yin Luo
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China
| | - Qinghai Huang
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People's Republic of China.
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Chodzyǹski KJ, Uzureau P, Nuyens V, Rousseau A, Coussement G, Zouaoui Boudjeltia K. The impact of arterial flow complexity on flow diverter outcomes in aneurysms. Sci Rep 2020; 10:10337. [PMID: 32587308 PMCID: PMC7316819 DOI: 10.1038/s41598-020-67218-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/28/2020] [Indexed: 12/03/2022] Open
Abstract
The flow diverter is becoming a standard device for treating cerebral aneurysms. The aim of this in vitro study was to evaluate the impact of flow complexity on the effectiveness of flow diverter stents in a cerebral aneurysm model. The flow pattern of a carotid artery was decomposed into harmonics to generate four flow patterns with different pulsatility indexes ranging from 0.72 to 1.44. The effect of flow diverters on the aneurysm was investigated by injecting red dye or erythrocytes as markers. The recorded images were postprocessed to evaluate the maximum filling of the aneurysm cavity and the washout time. There were significant differences in the cut-off flows between the markers, linked to the flow complexity. Increasing the pulsatility index altered the performance of the flow diverter. The red dye was more sensitive to changes in flow than the red blood cell markers. The flow cut-off depended on the diverter design and the diverter deployment step was crucial for reproducibility of the results. These results strongly suggest that flow complexity should be considered when selecting a flow diverter.
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Affiliation(s)
- Kamil Jerzy Chodzyǹski
- Laboratoire de Médecine Expérimentale (ULB222), CHU Charleroi, Université Libre de Bruxelles, 6110, Montigny le Tilleul, Belgium.
| | - Pierrick Uzureau
- Laboratoire de Médecine Expérimentale (ULB222), CHU Charleroi, Université Libre de Bruxelles, 6110, Montigny le Tilleul, Belgium
| | - Vincent Nuyens
- Laboratoire de Médecine Expérimentale (ULB222), CHU Charleroi, Université Libre de Bruxelles, 6110, Montigny le Tilleul, Belgium
| | - Alexandre Rousseau
- Laboratoire de Médecine Expérimentale (ULB222), CHU Charleroi, Université Libre de Bruxelles, 6110, Montigny le Tilleul, Belgium
| | | | - Karim Zouaoui Boudjeltia
- Laboratoire de Médecine Expérimentale (ULB222), CHU Charleroi, Université Libre de Bruxelles, 6110, Montigny le Tilleul, Belgium
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Aquarius R, de Korte A, Smits D, Gounis M, Verrijp K, Driessen L, Leenders W, de Vries J. The Importance of Wall Apposition in Flow Diverters. Neurosurgery 2020; 84:804-810. [PMID: 29659995 DOI: 10.1093/neuros/nyy092] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 02/27/2018] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND It is assumed that high pore densities in flow diverters (FDs) are beneficial for intracranial aneurysm (IA) healing. However, various animal studies are not conclusive on the issue, suggesting that other factors are in play. One important factor might be wall apposition. OBJECTIVE To (1) determine the relationship between FD pore density and aneurysm occlusion, and (2) determine the relationship between FD wall apposition and aneurysm occlusion. METHODS Saccular aneurysms were microsurgically created in the aorta of 36 Wistar rats. Twelve rats received a low pore density FD (10 pores/mm2), 12 rats received a high pore density FD (23 pores/mm2), and the remaining 12 rats served as a control group. Six animals from each group were sacrificed 1 and 3 mo after surgery. We determined aneurysm occlusion, the number of struts not in contact with the aorta wall, and the average distance from malapposed struts to aorta wall through histology. RESULTS No significant differences were found in aneurysm occlusion between the low pore density and high pore density groups (P > .05) after 1 and 3 mo of follow-up. The average number of malapposed struts was lower for the occluded aneurysm group (4.4 ± 1.9) compared to the nonoccluded aneurysm group (7.7 ± 2.6, P < .01). The average distance between malapposed struts and parent artery wall was lower for the occluded aneurysm group (33.9 μm ± 11.5 μm) than for the nonoccluded aneurysm group (48.7 μm ± 18.8 μm, P < .05). CONCLUSION Wall apposition is more important than pore density for aneurysm occlusion.
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Affiliation(s)
- René Aquarius
- Department of Neurosurgery, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Antonius de Korte
- Department of Neurosurgery, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Debby Smits
- Central Animal Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Matthew Gounis
- Department of Radiology, Division of Neuroimaging and Intervention and New England Center for Stroke Research University of Massachusetts Medical School, Worcester, Massachusetts
| | - Kiek Verrijp
- Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Léon Driessen
- Orthopaedic Research Laboratory Radboud University Medical Center, Nijmegen, The Netherlands
| | - William Leenders
- Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joost de Vries
- Department of Neurosurgery, Radboud University Medical Center, Nijmegen, The Netherlands
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Sadasivan C, Fiorella D. Preliminary in vitro angiographic comparison of the flow diversion behavior of Evolve and Pipeline devices. J Neurointerv Surg 2019; 12:616-620. [DOI: 10.1136/neurintsurg-2019-015455] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/29/2019] [Accepted: 10/31/2019] [Indexed: 11/04/2022]
Abstract
Background and purposeFlow diverters are increasingly used to treat a broad category of cerebral aneurysms. We conducted an in vitro study to angiographically compare the flow diversion effect of Surpass Evolve from Stryker Neurovascular with the Pipeline Shield Embolization Device from Medtronic Neurovascular.MethodsThree copies each of three carotid aneurysm geometries were manufactured from silicone. Evolve and Pipeline flow diverters were deployed in one copy of each geometry; the third copy was used as Control. High-speed angiography was acquired under pulsatile flow in each replica, contrast concentration-time curves within the aneurysms were recorded, and the curves were quantified with six parameters. The parameters were statistically evaluated to compare the flow diversion effect of both devices.ResultsThe Evolve showed greater flow diversion trends in almost all intra-geometry comparisons than the Pipeline. When aggregated over the three geometries, the Evolve was statistically significantly better than the Pipeline in four of the six parameters, and about the same or better (not statistically significant) than the Pipeline in the other two parameters.ConclusionsThe Evolve device demonstrated greater in vitro flow diversion effects than Pipeline. Comparative efficacy of the devices will need to be adjudicated based on clinical outcomes.
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Sadasivan C, Dholakia R, Peeling L, Gölitz P, Doerfler A, Lieber BB, Fiorella DJ, Woo HH. Angiographic assessment of the efficacy of flow diverter treatment for cerebral aneurysms. Interv Neuroradiol 2019; 25:655-663. [PMID: 31296064 DOI: 10.1177/1591019919860829] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The recent growth of neuro-endovascular treatment has rekindled interest in the use of angiographic techniques for flow assessment. Aneurysm treatment with flow diverters is particularly amenable to such analysis. We analyze contrast time-density curves - recorded within aneurysms before (pre) and immediately after (post) flow diverter implantation to estimate six-month treatment outcomes. METHODS Fifty-six patients with 65 aneurysms were treated with flow diverters at two institutions. A region of interest was drawn around the aneurysm perimeter in image sequences taken both pre and post angiography, and the temporal variation in grayscale intensity within the aneurysm (time-density curve) was recorded. Eleven parameters were quantified from each time-density curve. Aneurysm occlusion status was recorded six months post treatment. The change in parameters from pre to post treatment was statistically evaluated between aneurysm occluded and non-occluded groups. RESULTS Of the 11 parameters, eight were significantly different before and immediately after flow diversion. Considering the entire data set, none of the parameters was statistically different between the occluded and non-occluded groups. However, subgroup analyses showed that four variables were significantly different between the aneurysm occluded and non-occluded groups. The sensitivity of these variables to predict aneurysm occlusion at six months ranged from 60% to 89%, while the specificity ranged from 55% to 70%. CONCLUSIONS Device-induced intra-aneurysmal flow alterations quantified by simple aneurysmal time-density curves can potentially be used to predict long-term outcomes of flow diversion. Large multi-center studies will be required to confirm these findings. Patient-to-patient variability in coagulation may need to be incorporated for clinically relevant predictive values.
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Affiliation(s)
- Chander Sadasivan
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
| | - Ronak Dholakia
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
| | - Lissa Peeling
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
| | - Philipp Gölitz
- Department of Neuroradiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Arnd Doerfler
- Department of Neuroradiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Baruch B Lieber
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
| | - David J Fiorella
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
| | - Henry H Woo
- Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA
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Shen TW, Puccini B, Temnyk K, Herting S, Cardinal KO. Tissue-engineered aneurysm models for in vitro assessment of neurovascular devices. Neuroradiology 2019; 61:723-732. [DOI: 10.1007/s00234-019-02197-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 03/07/2019] [Indexed: 12/14/2022]
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10
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Fiorella D, Lylyk P, Szikora I, Kelly ME, Albuquerque FC, McDougall CG, Nelson PK. Curative cerebrovascular reconstruction with the Pipeline embolization device: the emergence of definitive endovascular therapy for intracranial aneurysms. J Neurointerv Surg 2018; 10:i9-i18. [DOI: 10.1136/jnis.2009.000083.rep] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 04/03/2009] [Indexed: 11/03/2022]
Abstract
Endovascular, endosaccular, coil embolization has emerged as an established therapy for both ruptured and unruptured cerebral aneurysms. However, many aneurysms are not cured using conventional endovascular techniques. Coil embolization often results in incomplete aneurysm occlusion or recanalization in the ensuing months after treatment. The Pipeline embolization device (PED; Chestnut Medical) represents a new generation endoluminal implant which is designed to treat aneurysms by reconstructing the diseased parent artery. Immediately after implantation, the PED functions to divert flow from the aneurysm, creating an environment conducive to thrombosis. With time, the PED is incorporated into the vessel wall as neointimal–endothelial overgrowth occurs along the construct. Ultimately, this process results in the durable complete exclusion of the aneurysm from the cerebrovasculature and a definitive endoluminal reconstruction of the diseased parent artery.
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Alkhalili K, Hannallah J, Cobb M, Chalouhi N, Philips JL, Echeverria AB, Jabbour P, Babiker MH, Frakes DH, Gonzalez LF. The Effect of Stents in Cerebral Aneurysms: A Review. Asian J Neurosurg 2018; 13:201-211. [PMID: 29682009 PMCID: PMC5898080 DOI: 10.4103/1793-5482.175639] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The etiology of up to 95% of cerebral aneurysms may be accounted for by hemodynamically-induced factors that create vascular injury. The purpose of this review is to describe key physical properties that stents have and how they affect cerebral aneurysms. We performed a two-step screening process. First, a structured search was performed using the PubMed database. The following search terms and keywords were used: “Hemodynamics,” “wall shear stress (WSS),” “velocity,” “viscosity,” “cerebral aneurysm,” “intracranial aneurysm,” “stent,” “flow diverter,” “stent porosity,” “stent geometry,” “stent configuration,” and “stent design.” Reports were considered if they included original data, discussed hemodynamic changes after stent-based treatment of cerebral aneurysms, examined the hemodynamic effects of stent deployment, and/or described the geometric characteristics of both stents and the aneurysms they were used to treat. The search strategy yielded a total of 122 articles, 61 were excluded after screening the titles and abstracts. Additional articles were then identified by cross-checking reference lists. The final collection of 97 articles demonstrates that the geometric characteristics and configurations of deployed stents influenced hemodynamic parameters such as aneurysmal WSS, inflow, and pressure. The geometric characteristics of the aneurysm and its position also had significant influences on intra-aneurysmal hemodynamics after treatment. In conclusion, changes in specific aneurysmal hemodynamic parameters that result from stenting relate to a number of factors including the geometric properties and configurations of deployed stents, the geometric properties of the aneurysm, and the pretreatment hemodynamics.
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Affiliation(s)
- Kenan Alkhalili
- Department of Surgery, University of Arizona, Tucson, Arizona, USA
| | - Jack Hannallah
- Department of Surgery, University of Arizona, Tucson, Arizona, USA
| | - Mary Cobb
- Division of Neurosurgery, Duke University, Durham, NC, USA
| | - Nohra Chalouhi
- Department of Neurosurgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Jessica L Philips
- Department of Neurosurgery, Thomas Jefferson University, Philadelphia, PA, USA
| | | | - Pascal Jabbour
- Department of Neurosurgery, Thomas Jefferson University, Philadelphia, PA, USA
| | | | - David H Frakes
- Division of Neurosurgery, Duke University, Durham, NC, USA
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Liu JM, Zhou Y, Li Y, Li T, Leng B, Zhang P, Liang G, Huang Q, Yang PF, Shi H, Zhang J, Wan J, He W, Liang C, Zhu G, Xu Y, Hong B, Yang X, Bai W, Tian Y, Zhang H, Li Z, Li Q, Zhao R, Fang Y, Zhao K. Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter: A Multicenter, Randomized, Controlled Clinical Trial (PARAT). AJNR Am J Neuroradiol 2018; 39:807-816. [PMID: 29599173 DOI: 10.3174/ajnr.a5619] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 02/26/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Although flow diverters have been reported with favorable clinical and angiographic outcomes in various literatures, randomized trials determining their true effectiveness and safety are still in lack. The Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter (PARAT) trial was designed to evaluate the safety and efficacy of the Tubridge flow diverter in the treatment of large or giant aneurysms in comparison with Enterprise stent-assisted coiling. MATERIALS AND METHODS This prospective, multicenter, randomized trial was conducted at 12 hospitals throughout China. Enrolled adults with unruptured large/giant intracranial aneurysms were randomly assigned (1:1) to receive either Enterprise stent-assisted coiling or Tubridge flow diverter implantation. The primary end point was complete occlusion at 6-month follow-up, while secondary end points included technical success, mortality, target vessel-related stroke, aneurysm bleeding, in-stent stenosis, parent artery occlusion, and the frequency of all adverse events. RESULTS Among 185 enrolled subjects, 41 withdrew before procedure initiation. Overall, 82 subjects underwent Tubridge implantation, and 62 subjects were primarily treated with stent-assisted coiling. The results of 6-month follow-up imaging included complete occlusion rates of 75.34% versus 24.53% for the Tubridge and stent-assisted coiling groups, respectively, with a calculated common odds ratio of 9.4 (95% confidence interval, 4.14-21.38; P < .001). There was a higher, nonsignificant frequency of complications for Tubridge subjects. Multivariate analysis showed a decreased stroke rate at the primary investigational site, with a marginal P value (P = .051). CONCLUSIONS This trial showed an obviously higher rate of large and giant aneurysm obliteration with the Tubridge FD over Enterprise stent-assisted coiling. However, this higher obliteration rate came at the cost of a nonsignificantly higher rate of complications. Investigational site comparisons suggested that a learning curve for flow-diverter implantation should be recognized and factored into trial designs.
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Affiliation(s)
- J-M Liu
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - Y Zhou
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - Y Li
- Department of Neurosurgery (Y.L., X.Y.), Tiantan Hospital, Beijing, China
| | - T Li
- Department of Interventional Radiology (T.L., W.B.), Henan Provincial People's Hospital, Henan Province, China
| | - B Leng
- Department of Neurosurgery (B.L., Y.T.), Huashan Hospital, Shanghai, China
| | - P Zhang
- Department of Neurosurgery (P.Z., H.Z.), Xuanwu Hospital, Beijing, China
| | - G Liang
- Department of Neurosurgery (G.L., Z.L.), General Hospital of Shenyang Military, Shenyang Province, China
| | - Q Huang
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - P-F Yang
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - H Shi
- Department of Neurosurgery (H.S.), First Clinical Hospital affiliated with Harbin Medical University, Heilongjiang Province, China
| | - J Zhang
- Department of Neurosurgery (J.Z.), Second Affiliated Hospital of Zhejiang University, Hangzhou Municipality, Zhejiang, China
| | - J Wan
- Department of Neurosurgery (J.W.), Renji Hospital, Shanghai, China
| | - W He
- Department of Neurosurgery (W.H.), Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - C Liang
- Department of Neurosurgery (C.L.), First Hospital of China Medical University, Shenyang Municipality, Liaoning, China
| | - G Zhu
- Department of Neurosurgery (G.Z.), Southwest Hospital, Chongqing Municipality, China
| | - Y Xu
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - B Hong
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - X Yang
- Department of Neurosurgery (Y.L., X.Y.), Tiantan Hospital, Beijing, China
| | - W Bai
- Department of Interventional Radiology (T.L., W.B.), Henan Provincial People's Hospital, Henan Province, China
| | - Y Tian
- Department of Neurosurgery (B.L., Y.T.), Huashan Hospital, Shanghai, China
| | - H Zhang
- Department of Neurosurgery (P.Z., H.Z.), Xuanwu Hospital, Beijing, China
| | - Z Li
- Department of Neurosurgery (G.L., Z.L.), General Hospital of Shenyang Military, Shenyang Province, China
| | - Q Li
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - R Zhao
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - Y Fang
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
| | - K Zhao
- From the Department of Neurosurgery, (J.-m.L., Y.Z., P.-f.Y., B.H., Y.X., Q.L., R.Z., Y.F., K.Z., Q.H.), Shanghai Changhai Hospital, Shanghai, China
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Giorgianni A, Pellegrino C, Minotto R, Mercuri A, Frattini L, Baruzzi F, Valvassori L. Flow-diverter stenting of post-traumatic bilateral anterior cerebral artery pseudoaneurysm: A case report. Interv Neuroradiol 2018; 21:23-8. [PMID: 25934771 DOI: 10.1177/1591019915575441] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The use of flow-diverter (FD) stents in recent years has positively changed the therapeutic approach to some vascular diseases, especially of certain types of aneurysms. This paper describes the case of a young patient after a major head trauma causing multiple skull fractures. The trauma occasioned two pseudoaneurysms from the A1 segment of the right anterior cerebral artery and from the A2 segment of the left anterior cerebral artery. Both lesions were treated with two Pipeline devices (ev3, Irvine, CA, USA) in two different sessions. The CT study and angiographic investigations performed in the following month showed a complete resolution of the post-traumatic pseudoaneurysmal lesions. Although the use of FD stents is described in the literature, particularly in the treatment of selected aneurysms, this paper shows good technical results in the use of these stents in cases of intracranial post-traumatic pseudoaneurysms with clinical improvement.
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Affiliation(s)
| | - Carlo Pellegrino
- Departement of Neuroradiology, Ospedale di Circolo, Varese, Italy
| | - Renzo Minotto
- Departement of Neuroradiology, Ospedale di Circolo, Varese, Italy
| | - Anna Mercuri
- Departement of Neuroradiology, Ospedale di Circolo, Varese, Italy
| | - Lara Frattini
- Departement of Anesthesiology, Ospedale di Circolo, Varese, Italy
| | - Fabio Baruzzi
- Departement of Neuroradiology, Ospedale di Circolo, Varese, Italy
| | - Luca Valvassori
- Departement of Neuroradiology, Ospedale Niguarda Ca' Granda, Milan, Italy
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14
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Dholakia RJ, Kappel AD, Pagano A, Woo HH, Lieber BB, Fiorella DJ, Sadasivan C. In vitro angiographic comparison of the flow-diversion performance of five neurovascular stents. Interv Neuroradiol 2017; 24:150-161. [PMID: 29239685 DOI: 10.1177/1591019917748317] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background and purpose Data differentiating flow diversion properties of commercially available low- and high-porosity stents are limited. This in vitro study applies angiographic analysis of intra-aneurysmal flow to compare the flow-diversion performance of five neurovascular devices in idealized sidewall and bifurcation aneurysm models. Methods Five commercial devices (Enterprise, Neuroform, LVIS, FRED, and Pipeline) were implanted in silicone sidewall and bifurcation aneurysm models under physiological average flow of blood analog fluid. High-speed angiographic images were acquired pre- and post-device implantation and contrast concentration-time curves within the aneurysm were recorded. The curves were quantified with five parameters to assess changes in contrast transport, and thus aneurysm hemodynamics, due to each device. Results Inter-device flow-diversion performance was more easily distinguished in the sidewall model than the bifurcation model. There were no obvious overall statistical trends in the bifurcation parameters but the Pipeline performed marginally better than the other devices. In the sidewall geometry, overall evidence suggests that the LVIS performed better than the Neuroform and Enterprise. The Pipeline and FRED devices were statistically superior to the three stents and Pipeline was superior to FRED in all sidewall parameters evaluated. Conclusions Based on this specific set of experiments, lower-porosity flow diverters perform significantly better in reducing intra-aneurysmal flow activity than higher-porosity stents in sidewall-type geometries. The LVIS device is potentially a better flow diverter than the Neuroform and Enterprise devices, while the Pipeline is potentially better than the FRED.
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Affiliation(s)
- Ronak J Dholakia
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - Ari D Kappel
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - Andrew Pagano
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - Henry H Woo
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - Baruch B Lieber
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - David J Fiorella
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
| | - Chander Sadasivan
- Department of Neurological Surgery, 12301 Stony Brook University , Stony Brook, NY, USA
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15
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Jou LD. In vitro digital subtraction angiographic evaluation of flow diverters in a patient-specific aneurysm. Interv Neuroradiol 2017; 23:260-266. [PMID: 28604187 DOI: 10.1177/1591019917694023] [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] [Indexed: 11/17/2022] Open
Abstract
Background The importance of both porosity and pore density of a flow diverter is well recognized in treatment of intracranial aneurysms; however, understanding of the effect of individual wire (wire number and size) is critical in improving device design and use. Methods A total of 10 multi-layered flow diverters with different wire numbers (32, 48, 56, and 72) and sizes (30, 35, and 40 µm) were implanted into identical patient-specific middle cerebral artery aneurysm models. Digital subtraction angiography was acquired at 30 f/s and X-ray signals at three selected regions of interest were compared to determine the amount of intra-aneurysmal flow. Results Flow reduction ranged from 19% for a high porosity (82%) and low pore density (5 pores/mm2) to nearly 80% for a low porosity (49%) and high pore density (36 pores/mm2). An increase in the wire number from 32 to 72 lowers intra-aneurysmal flow and redirects the flow jet; however, the effect of wire size is not observed. Conclusions In our in vitro angiographic study, flow jet is influenced by the wire number in a device qualitatively; quantitatively, intra-aneurysmal flow is affected by both the porosity and pore density. A 2.5 mm device performs better in flow diversion of a middle cerebral artery (MCA) aneurysm than a 3 mm device with the same wire size and wire number, but thicker wires do not lead to better flow diversion.
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Affiliation(s)
- Liang-Der Jou
- Department of Neurosurgery, Houston Methodist Hospital, Houston, TX, USA
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16
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Cebral JR, Mut F, Chung BJ, Spelle L, Moret J, van Nijnatten F, Ruijters D. Understanding Angiography-Based Aneurysm Flow Fields through Comparison with Computational Fluid Dynamics. AJNR Am J Neuroradiol 2017; 38:1180-1186. [PMID: 28385882 DOI: 10.3174/ajnr.a5158] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/25/2017] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Hemodynamics is thought to be an important factor for aneurysm progression and rupture. Our aim was to evaluate whether flow fields reconstructed from dynamic angiography data can be used to realistically represent the main flow structures in intracranial aneurysms. MATERIALS AND METHODS DSA-based flow reconstructions, obtained during interventional treatment, were compared qualitatively with flow fields obtained from patient-specific computational fluid dynamics models and quantitatively with projections of the computational fluid dynamics fields (by computing a directional similarity of the vector fields) in 15 cerebral aneurysms. RESULTS The average similarity between the DSA and the projected computational fluid dynamics flow fields was 78% in the parent artery, while it was only 30% in the aneurysm region. Qualitatively, both the DSA and projected computational fluid dynamics flow fields captured the location of the inflow jet, the main vortex structure, the intrasaccular flow split, and the main rotation direction in approximately 60% of the cases. CONCLUSIONS Several factors affect the reconstruction of 2D flow fields from dynamic angiography sequences. The most important factors are the 3-dimensionality of the intrasaccular flow patterns and inflow jets, the alignment of the main vortex structure with the line of sight, the overlapping of surrounding vessels, and possibly frame rate undersampling. Flow visualization with DSA from >1 projection is required for understanding of the 3D intrasaccular flow patterns. Although these DSA-based flow quantification techniques do not capture swirling or secondary flows in the parent artery, they still provide a good representation of the mean axial flow and the corresponding flow rate.
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Affiliation(s)
- J R Cebral
- From the Bioengineering Department (J.R.C., F.M., B.J.C.), Volgenau School of Engineering, George Mason University, Fairfax, Virginia
| | - F Mut
- From the Bioengineering Department (J.R.C., F.M., B.J.C.), Volgenau School of Engineering, George Mason University, Fairfax, Virginia
| | - B J Chung
- From the Bioengineering Department (J.R.C., F.M., B.J.C.), Volgenau School of Engineering, George Mason University, Fairfax, Virginia
| | - L Spelle
- Faculté de Médecine Paris-Sud (L.S.), Le Kremlin-Bicetre, France
| | - J Moret
- Interventional Neuroradiology (J.M.), Beaujon University Hospital, Clichy, France
| | - F van Nijnatten
- Image Guided Therapy Innovation (F.v.N., D.R.), Philips Healthcare, Best, the Netherlands
| | - D Ruijters
- Image Guided Therapy Innovation (F.v.N., D.R.), Philips Healthcare, Best, the Netherlands
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17
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Aquarius R, Smits D, Gounis MJ, Leenders WPJ, de Vries J. Flow diverter implantation in a rat model of sidewall aneurysm: a feasibility study. J Neurointerv Surg 2017; 10:88-92. [DOI: 10.1136/neurintsurg-2016-012878] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 11/04/2022]
Abstract
BackgroundMore challenging animal models are needed to elucidate the efficacy of flow diverter (FD) designs and the mechanisms behind observed complications. The purpose of this study is to demonstrate the feasibility of implanting a FD in a sidewall aneurysm rat model.MethodsAn end-to-side anastomosis was created in the abdominal aorta of 36 rats using a decellularized donor pouch. A FD was subsequently implanted.ResultsAfter up to 3 months of follow-up, we observed that rats displayed normal growth and behavior. Mortality within the groups was low (2 rats, 5.6%). All aneurysms thrombosed after FD implantation and showed progressive soft tissue replacement of the thrombus during follow-up. The abdominal aortas remained patent.ConclusionsThis model can be used to test the effects of FDs in future studies.
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18
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Dholakia R, Sadasivan C, Fiorella DJ, Woo HH, Lieber BB. Hemodynamics of Flow Diverters. J Biomech Eng 2017; 139:2569375. [DOI: 10.1115/1.4034932] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Indexed: 01/17/2023]
Abstract
Cerebral aneurysms are pathological focal evaginations of the arterial wall at and around the junctions of the circle of Willis. Their tenuous walls predispose aneurysms to leak or rupture leading to hemorrhagic strokes with high morbidity and mortality rates. The endovascular treatment of cerebral aneurysms currently includes the implantation of fine-mesh stents, called flow diverters, within the parent artery bearing the aneurysm. By mitigating flow velocities within the aneurysmal sac, the devices preferentially induce thrombus formation in the aneurysm within hours to days. In response to the foreign implant, an endothelialized arterial layer covers the luminal surface of the device over a period of days to months. Organization of the intraneurysmal thrombus leads to resorption and shrinkage of the aneurysm wall and contents, eventually leading to beneficial remodeling of the pathological site to a near-physiological state. The devices' primary function of reducing flow activity within aneurysms is corollary to their mesh structure. Complete specification of the device mesh structure, or alternately device permeability, necessarily involves the quantification of two variables commonly used to characterize porous media—mesh porosity and mesh pore density. We evaluated the flow alteration induced by five commercial neurovascular devices of varying porosity and pore density (stents: Neuroform, Enterprise, and LVIS; flow diverters: Pipeline and FRED) in an idealized sidewall aneurysm model. As can be expected in such a model, all devices substantially reduced intraneurysmal kinetic energy as compared to the nonstented case with the coarse-mesh stents inducing a 65–80% reduction whereas the fine-mesh flow diverters induced a near-complete flow stagnation (∼98% reduction). We also note a trend toward greater device efficacy (lower intraneurysmal flow) with decreasing device porosity and increasing device pore density. Several such flow studies have been and are being conducted in idealized as well as patient-derived geometries with the overarching goals of improving device design, facilitating treatment planning (what is the optimal device for a specific aneurysm), and predicting treatment outcome (will a specific aneurysm treated with a specific device successfully occlude over the long term). While the results are generally encouraging, there is poor standardization of study variables between different research groups, and any consensus will only be reached after standardized studies are conducted on collectively large datasets. Biochemical variables may have to be incorporated into these studies to maximize predictive values.
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Affiliation(s)
- Ronak Dholakia
- Department of Neurological Surgery, Stony Brook University Medical Center, Stony Brook, NY 11794
| | - Chander Sadasivan
- Department of Neurological Surgery, Stony Brook University Medical Center, Stony Brook, NY 11794
| | - David J. Fiorella
- Department of Neurological Surgery, Stony Brook University Medical Center, Stony Brook, NY 11794
| | - Henry H. Woo
- Department of Neurological Surgery, Stony Brook University Medical Center, Stony Brook, NY 11794
| | - Baruch B. Lieber
- Professor Department of Neurological Surgery, Stony Brook University Medical Center, HSC T12, Room 080, 100 Nicolls Road, Stony Brook, NY 11794-8122 e-mail:
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19
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Gascou G, Ferrara R, Ambard D, Sanchez M, Lobotesis K, Jourdan F, Costalat V. The pressure reduction coefficient: A new parameter to assess aneurysmal blood stasis induced by flow diverters/disruptors. Interv Neuroradiol 2016; 23:41-46. [PMID: 27913801 DOI: 10.1177/1591019916673219] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background and purpose Pore density (PD), surface metal coverage (SMC) and the number of wires are all different parameters which can influence the efficacy of a flow disruptor/diverter. Nevertheless, the relative importance of a parameter to induce intra-aneurysmal blood stasis is still poorly evaluated. Therefore, comparison between devices based on a unique value is not reliable. The aim of this study was to propose a new bench top parameter (the pressure reduction coefficient (PRC; ξ)) in order to assess the global haemodynamic effect of each flow diverter/disruptor to slow flow. Methods Eight devices were tested in vitro during three different flow conditions. For the eight devices, the PRC was computed at different volumetric flow rates to characterise flow reduction. Comparison was made with SMC, PD and the number of wires. Results The PRC obtained for flow disruptors was on average 1.5 times more efficient in reducing flow compared to flow diverters. PD (mm2) ranged from 24 to 38 for flow diverters and did not independently correlate with the PRC. The SMC of flow diverters ranged from 25% to 70%, and ranged from 20% to 100% for flow disruptors, without independent correlation to the PRC. The number of wires ranged from 48 to 96 for the flow diverters and did not correlate independently to the PRC. Conclusion There were no direct correlations between individual device characteristics and the PRC, suggesting a multifaceted and interrelating association of the overall design of each implant. Hence, the PRC could be used as a simple, reliable parameter to assess the overall capacity of flow disruptors/diverters to induce intra-aneurysmal blood stasis.
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Affiliation(s)
- Gregory Gascou
- 1 Department of Neuroradiology, CHU Gui de Chauliac, Montpellier, France
| | - Riccardo Ferrara
- 2 Laboratoire de mécanique et de génie civil, Universite de Montpellier, Montpellier, France
| | - Dominique Ambard
- 2 Laboratoire de mécanique et de génie civil, Universite de Montpellier, Montpellier, France
| | - Mathieu Sanchez
- 2 Laboratoire de mécanique et de génie civil, Universite de Montpellier, Montpellier, France
| | - Kyriakos Lobotesis
- 3 Charing Cross Hospital, Imperial College Hospitals, NHS Trust, London, UK
| | - Franck Jourdan
- 2 Laboratoire de mécanique et de génie civil, Universite de Montpellier, Montpellier, France
| | - Vincent Costalat
- 1 Department of Neuroradiology, CHU Gui de Chauliac, Montpellier, France
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20
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Jou LD, Desai VR, Britz GW. In vitro investigation of contrast flow jet timing in patient-specific intracranial aneurysms. Quant Imaging Med Surg 2016; 6:134-43. [PMID: 27190765 DOI: 10.21037/qims.2016.03.06] [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] [Indexed: 11/06/2022]
Abstract
BACKGROUND The direction and magnitude of intra-aneurysmal flow jet are significant risk factors of subarachnoid hemorrhage, and the change of flow jet during an endovascular procedure has been used for prediction of aneurysm occlusion or whether an additional flow diverter (FD) is warranted. However, evaluation of flow jets is often unreliable due to a large variation of flow jet on the digital subtraction angiograms, and this flow pattern variation may result in incorrect clinical diagnosis Therefore, factors contributing to the variation in flow jet are examined at an in vitro setting, and the findings can help us to understand the nature of flow jet and devise a better plan to quantify the aneurysmal hemodynamics accurately. METHODS Intra-aneurysmal flows in three patient-specific aneurysms between 11 and 25 mm were investigated in vitro, and a FD was deployed in each aneurysm model. X-ray imaging of these models were performed at injection rates between 0.2 and 2 mL/s. Pulsatile blood pump and aneurysm model were imaged together to determine the timing of flow jet. RESULTS The contrast bolus arrives at the aneurysm early at high contrast injection rates. The flow patterns with slow injection rates exhibit strong inertia that is associated with the systole flow. Flow jets arrive at the aneurysms at the peak systole when the bolus is injected at 0.2 mL/s. The contrast-to-signal ratio is the highest at the injection rate of 0.5 mL/s. Effect of flow diversion can only be assessed at an injection rate greater than 0.5 mL/s. CONCLUSIONS Intra-aneurysmal flow jet is highly dependent on the injection rate of the contrast agent. For the internal carotid artery (ICA) aneurysms, the systolic flows can be visualized at slow injection rates (<0.5 mL/s), while the diastolic flow jets are visible at higher injection rates (>1 mL/s). Dependence of flow jet on the contrast injection rate has serious clinical implications and needs to be considered during diagnostic procedures; a protocol with a consistent injection rate is highly recommended.
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Affiliation(s)
- Liang-der Jou
- Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas 77030, USA
| | - Virendra R Desai
- Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas 77030, USA
| | - Garvin W Britz
- Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas 77030, USA
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Chalouhi N, Daou B, Kung D, Zanaty M, Phillips JL, Tjoumakaris S, Starke RM, Hasan D, Polifka A, Salas S, Rosenwasser RH, Jabbour PM. Fate of the Ophthalmic Artery After Treatment With the Pipeline Embolization Device. Neurosurgery 2016; 77:581-4; discussion 584. [PMID: 26191974 DOI: 10.1227/neu.0000000000000887] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Flow diverters have emerged as a major tool in the treatment of cerebral aneurysms. A crucial issue with the use of flow diverters is the patency of side branches covered by the device, most importantly the ophthalmic artery (OA). OBJECTIVE To assess the patency of the OA after coverage with the pipeline embolization device (PED). METHODS All patients who had a PED covering the OA and in whom angiographic follow-up was available were included in the study. The patency of the OA at follow-up was systematically evaluated by 2 authors who were not involved in the procedure. RESULTS Of 95 treated patients, the OA was covered by 1 PED in 81 patients (85%) and by 2 PEDs in 14 patients (15%). Mean angiographic follow-up was 7.5 months, ranging from 3 to 24 months. At the latest follow-up, the OA remained patent in 85 patients (89%), showed diminished flow in 4 patients (4%), and was occluded in 6 patients (7%). Only 1 patient had clinical symptoms related to OA occlusion. In multivariable analysis, larger aneurysm size predicted OA occlusion (P = .04). There was also a strong trend for younger age (P = .06) and coverage by more than 1 device (P = .07). CONCLUSION Treatment of internal carotid artery aneurysms with the PED preserves the patency of the OA in most cases. The occlusion of the OA in the few cases where it occurs is usually a clinically irrelevant event. Minimizing the number of PEDs across the OA is crucial to preserve its patency.
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Affiliation(s)
- Nohra Chalouhi
- *Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania; ‡Department of Neurosurgery, University of Iowa, Iowa City, Iowa
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Ma J, You Z, Peach T, Byrne J, Rizkallah RR. A new flow diverter stent for direct treatment of intracranial aneurysm. J Biomech 2015; 48:4206-13. [DOI: 10.1016/j.jbiomech.2015.10.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/10/2015] [Accepted: 10/18/2015] [Indexed: 11/29/2022]
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Gentric JC, Salazkin I, Gevry G, Raymond J, Darsaut T. Compaction of flow diverters improves occlusion of experimental wide-necked aneurysms. J Neurointerv Surg 2015; 8:1072-7. [PMID: 26453605 DOI: 10.1136/neurintsurg-2015-012016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/17/2015] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Flow diverters (FDs) are increasingly used in the treatment of wide-necked aneurysms. OBJECTIVE To examine the hypothesis that intentional FD compaction might improve aneurysm occlusion rates. METHODS Bilateral wide-necked carotid aneurysms were created in 12 dogs. Endovascular treatment was performed 1 month later, using Pipeline embolization devices deployed with compaction across the aneurysm neck (n=12). Group 1a consisted of aneurysms treated with a single compacted FD (n=8), while group 1b aneurysms required two compacted FDs (n=4). Control aneurysms were treated with a single non-compacted FD (group 3; n=6), or not treated (group 4; n=4). Angiographic results were compared at 3 months. Pathology specimens were photographed and the neointimal coverage of devices scored using an ordinal grading system. RESULTS Twenty-two of 24 aneurysms were patent at 1 month. Deployment with compaction was successful in eight cases (group 1a aneurysms). The compaction maneuver led to immediate FD prolapse into the aneurysm in four cases, rescued by deploying a second, telescoping FD (forming group 1b aneurysms). One compacted device later migrated distally, leaving the aneurysm untreated. Angiographic results differed significantly between groups (p=0.0002). At 3 months, aneurysms successfully treated with a single compacted FD were more often occluded at 3 months (7/7) than aneurysms flow-diverted without compaction (2/6; p=0.021). All aneurysms treated with two compacted FDs were occluded, while all untreated aneurysms remained patent. There were no parent vessel stenoses. CONCLUSIONS Compaction of FDs can improve angiographic occlusion of experimental wide-necked aneurysms.
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Affiliation(s)
- Jean-Christophe Gentric
- Department of Radiology, Centre Hospitalier de l'Université de Montréal (CHUM), Notre-Dame Hospital, Montreal, Quebec, Canada Groupe d'étude de la Thrombose en Bretagne Occidentale (GETBO, EA 3878), Brest, France
| | - Igor Salazkin
- Laboratory of Interventional Neuroradiology, Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada
| | - Guylaine Gevry
- Laboratory of Interventional Neuroradiology, Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada
| | - Jean Raymond
- Department of Radiology, Centre Hospitalier de l'Université de Montréal (CHUM), Notre-Dame Hospital, Montreal, Quebec, Canada Laboratory of Interventional Neuroradiology, Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada
| | - Tim Darsaut
- Division of Neurosurgery, Department of Surgery, University of Alberta Hospital, Mackenzie Health Sciences Centre, Edmonton, Alberta, Canada
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Chalouhi N, Polifka A, Daou B, Kung D, Barros G, Tjoumakaris S, Gonzalez LF, Starke RM, Hasan D, Judy B, Rosenwasser RH, Jabbour P. In-Pipeline Stenosis. Neurosurgery 2015. [DOI: 10.1227/neu.0000000000000908] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND:
The Pipeline Embolization Device is a widely utilized flow diverter in the treatment of intracranial aneurysms.
OBJECTIVE:
To assess the incidence, clinical significance, predictors, and outcomes of in-Pipeline stenosis (IPS).
METHODS:
Angiographic studies in 139 patients treated between 2011 and 2013 were independently reviewed by 2 authors for the presence of IPS. Multivariable logistic regression analysis was conducted to determine predictors of IPS.
RESULTS:
A total of 21 (15.8%) patients demonstrated some degree of IPS during the follow-up period at a mean time point of 6.7 months (range, 3–24 months). The stenosis was mild (<50%) in 11 patients, moderate (50%-75%) in 5, and severe (>75%) in 6. None were symptomatic or required further intervention. Sixteen of these 22 patients (73%) had IPS detected within 6 months. IPS was noted in 7.6% (1/13) of patients with posterior circulation aneurysms vs 16.7% (21/126) of those with anterior circulation aneurysms (P = .03). The rate of IPS was 60% (3/5) in patients who did not receive aspirin vs only 14.2% (19/134) in those who received aspirin (P = .02). In multivariable analysis, no aspirin therapy (odds ratio, 10.0; 95% confidence interval, 1.4–67.7; P = .02) and internal carotid artery aneurysm location (odds ratio, 3.1; 95% confidence interval, 1.1–8.8; P = .03) were strong independent predictors of IPS.
CONCLUSION:
IPS is a common, early, and mostly benign complication. Patients with internal carotid artery aneurysms are more likely to develop IPS. Aspirin plays a key role in preventing IPS. The results of this study further support the safety of flow diverters.
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Affiliation(s)
- Nohra Chalouhi
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Adam Polifka
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Badih Daou
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - David Kung
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Guilherme Barros
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Stavropula Tjoumakaris
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - L. Fernando Gonzalez
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Robert M. Starke
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - David Hasan
- Department of Neurosurgery, University of Iowa, Iowa City, Iowa
| | - Brendan Judy
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Robert H. Rosenwasser
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
| | - Pascal Jabbour
- Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania
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Ohta M, Anzai H, Miura Y, Nakayama T. Parametric study of porous media as substitutes for flow-diverter stent. BIOMATERIALS AND BIOMECHANICS IN BIOENGINEERING 2015. [DOI: 10.12989/bme.2015.2.2.111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Gascou G, Lobotesis K, Brunel H, Machi P, Riquelme C, Eker O, Bonafé A, Costalat V. Extra-aneurysmal flow modification following pipeline embolization device implantation: focus on regional branches, perforators, and the parent vessel. AJNR Am J Neuroradiol 2014; 36:725-31. [PMID: 25523592 DOI: 10.3174/ajnr.a4191] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/19/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Flow-diverter technology has proved to be a safe and effective treatment for intracranial aneurysm based on the concept of flow diversion allowing parent artery and collateral preservation and aneurysm healing. We investigated the patency of covered side branches and flow modification within the parent artery following placement of the Pipeline Embolization Device in the treatment of intracranial aneurysms. MATERIALS AND METHODS Sixty-six aneurysms in 59 patients were treated with 96 Pipeline Embolization Devices. We retrospectively reviewed imaging and clinical results during the postoperative period at 6 and 12 months to assess flow modification through the parent artery and side branches. Reperfusion syndrome was assessed by MR imaging and clinical evaluation. RESULTS Slow flow was observed in 13 of 68 (19.1%) side branches covered by the Pipeline Embolization Device. It was reported in all cases of anterior cerebral artery coverage, in 3/5 cases of M2-MCA coverage, and in 5/34 (14.7%) cases of ophthalmic artery coverage. One territorial infarction was observed in a case of M2-MCA coverage, without arterial occlusion. One case of deep Sylvian infarct was reported in a case of coverage of MCA perforators. Two ophthalmic arteries (5.9%) were occluded, and 11 side branches (16.2%) were narrowed at 12 months' follow-up; patients remained asymptomatic. Parent vessel flow modification was responsible for 2 cases (3.4%) of reperfusion syndrome. Overall permanent morbidity and mortality rates were 5.2% and 6.9%, respectively. We did not report any permanent deficit or death in case of slow flow observed within side branches. CONCLUSIONS After Pipeline Embolization Device placement, reperfusion syndrome was observed in 3.4%, and territorial infarction, in 3.4%. Delayed occlusion of ophthalmic arteries and delayed narrowing of arteries covered by the Pipeline Embolization Device were observed in 5.9% and 16.2%, respectively. No permanent morbidity or death was related to side branch coverage at midterm follow-up.
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Affiliation(s)
- G Gascou
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
| | - K Lobotesis
- Department of Imaging (K.L.), Imperial College Healthcare NHS Trust, Charing Cross Hospital, United Kingdom
| | - H Brunel
- Department of Neuroradiology (H.B.), CHU La Timone, Marseille, France
| | - P Machi
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
| | - C Riquelme
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
| | - O Eker
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
| | - A Bonafé
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
| | - V Costalat
- From the Department of Neuroradiology (G.G., P.M., C.R., O.E., A.B., V.C.), CHU Gui de Chauliac, Montpellier, France
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Hodis S, Ding YH, Dai D, Lingineni R, Mut F, Cebral J, Kallmes D, Kadirvel R. Relationship between aneurysm occlusion and flow diverting device oversizing in a rabbit model. J Neurointerv Surg 2014; 8:94-8. [PMID: 25387731 DOI: 10.1136/neurintsurg-2014-011487] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 10/24/2014] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND PURPOSE Implanted, actual flow diverter pore density is thought to be strongly influenced by proper matching between the device size and parent artery diameter. The objective of this study was to characterize the correlation between device sizing, metal coverage, and the resultant occlusion of aneurysms following flow diverter treatment in a rabbit model. METHODS Rabbit saccular aneurysms were treated with flow diverters (iso-sized to proximal parent artery, 0.5 mm oversized, or 1.0 mm oversized, respectively, n=6 for each group). Eight weeks after implantation, the angiographic degree of aneurysm occlusion was graded (complete, near-complete, or incomplete). The ostium of the explanted aneurysm covered with the flow diverter struts was photographed. Based on gross anatomic findings, the metal coverage and pore density at the ostium of the aneurysm were calculated and correlated with the degree of aneurysm occlusion. RESULTS Angiographic results showed there were no statistically significant differences in aneurysm geometry and occlusion among groups. The mean parent artery diameter to flow diverter diameter ratio was higher in the 1.0 mm oversized group than in the other groups. Neither the percentage metal coverage nor the pore density showed statistically significant differences among groups. Aneurysm occlusion was inversely correlated with the ostium diameter, irrespective of the size of the device implanted. CONCLUSIONS Device sizing alone does not predict resultant pore density or metal coverage following flow diverter implantation in the rabbit aneurysm model. Aneurysm occlusion was not impacted by either metal coverage or pore density, but was inversely correlated with the diameter of the ostium.
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Affiliation(s)
- Simona Hodis
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Yong-Hong Ding
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Daying Dai
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Ravi Lingineni
- Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA
| | - Fernando Mut
- Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA
| | - Juan Cebral
- Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA
| | - David Kallmes
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
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Chung B, Mut F, Kadirvel R, Lingineni R, Kallmes DF, Cebral JR. Hemodynamic analysis of fast and slow aneurysm occlusions by flow diversion in rabbits. J Neurointerv Surg 2014; 7:931-5. [PMID: 25332410 DOI: 10.1136/neurintsurg-2014-011412] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 09/22/2014] [Indexed: 11/03/2022]
Abstract
PURPOSE To assess hemodynamic differences between aneurysms that occlude rapidly and those occluding in delayed fashion after flow diversion in rabbits. METHODS Thirty-six elastase-induced aneurysms in rabbits were treated with flow diverting devices. Aneurysm occlusion was assessed angiographically immediately before they were sacrificed at 1 (n=6), 2 (n=4), 4 (n=8) or 8 weeks (n=18) after treatment. The aneurysms were classified into a fast occlusion group if they were completely or near completely occluded at 4 weeks or earlier and a slow occlusion group if they remained incompletely occluded at 8 weeks. The immediate post-treatment flow conditions in aneurysms of each group were quantified using subject-specific computational fluid dynamics and statistically compared. RESULTS Nine aneurysms were classified into the fast occlusion group and six into the slow occlusion group. Aneurysms in the fast occlusion group were on average significantly smaller (fast=0.9 cm, slow=1.393 cm, p=0.024) and had smaller ostia (fast=0.144 cm2, slow=0.365 cm2, p=0.015) than aneurysms in the slow occlusion group. They also had a lower mean post-treatment inflow rate (fast=0.047 mL/s, slow=0.155 mL/s, p=0.0239), kinetic energy (fast=0.519 erg, slow=1.283 erg, p=0.0468), and velocity (fast=0.221 cm/s, slow=0.506 cm/s, p=0.0582). However, the differences in the latter two variables were only marginally significant. CONCLUSIONS Hemodynamic conditions after flow diversion treatment of cerebral aneurysms in rabbits are associated with the subsequent aneurysm occlusion time. Specifically, smaller inflow rate, kinetic energy, and velocity seem to promote faster occlusions, especially in smaller and small-necked aneurysms. These results are consistent with previous studies based on clinical series.
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Affiliation(s)
- Bongjae Chung
- Department of Bioengineering, Volgenau School of Engineering, George Mason University, 4400 University Drive, MSN 2A1, Fairfax, VA 22030, USA
| | - Fernando Mut
- Department of Bioengineering, Volgenau School of Engineering, George Mason University, 4400 University Drive, MSN 2A1, Fairfax, VA 22030, USA
| | | | - Ravi Lingineni
- Department of Health Sciences and Research, Mayo Clinic, Rochester, Minnesota, USA
| | - David F Kallmes
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Juan R Cebral
- Department of Bioengineering, Volgenau School of Engineering, George Mason University, 4400 University Drive, MSN 2A1, Fairfax, VA 22030, USA
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Gölitz P, Struffert T, Rösch J, Ganslandt O, Knossalla F, Doerfler A. Cerebral aneurysm treatment using flow-diverting stents: in-vivo visualization of flow alterations by parametric colour coding to predict aneurysmal occlusion: preliminary results. Eur Radiol 2014; 25:428-35. [DOI: 10.1007/s00330-014-3411-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 07/07/2014] [Accepted: 08/25/2014] [Indexed: 11/29/2022]
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Cebral JR, Mut F, Raschi M, Ding YH, Kadirvel R, Kallmes D. Strategy for analysis of flow diverting devices based on multi-modality image-based modeling. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2014; 30:951-968. [PMID: 24719392 PMCID: PMC4188720 DOI: 10.1002/cnm.2638] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 06/03/2023]
Abstract
Quantification and characterization of the hemodynamic environment created after flow diversion treatment of cerebral aneurysms is important to understand the effects of flow diverters and their interactions with the biology of the aneurysm wall and the thrombosis process that takes place subsequently. This paper describes the construction of multi-modality image-based subject-specific CFD models of experimentally created aneurysms in rabbits and subsequently treated with flow diverters. Briefly, anatomical models were constructed from 3D rotational angiography images, flow conditions were derived from Doppler ultrasound measurements, stent models were created and virtually deployed, and the results were compared with in vivo digital subtraction angiography and Doppler ultrasound images. The models were capable of reproducing in vivo observations, including velocity waveforms measured in the parent artery, peak velocity values measured in the aneurysm, and flow structures observed with digital subtraction angiography before and after deployment of flow diverters. The results indicate that regions of aneurysm occlusion after flow diversion coincide with slow and smooth flow patterns, whereas regions still permeable at the time of animal sacrifice were observed in parts of the aneurysm exposed to larger flow activity, that is, higher velocities, more swirling, and more complex flow structures.
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Affiliation(s)
- Juan R. Cebral
- Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA
| | - Fernando Mut
- Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA
| | - Marcelo Raschi
- Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA
| | - Yong-Hong Ding
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | | | - David Kallmes
- Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
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31
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Benz T, Kowarschik M, Endres J, Redel T, Demirci S, Navab N. A Fourier-based approach to the angiographic assessment of flow diverter efficacy in the treatment of cerebral aneurysms. IEEE TRANSACTIONS ON MEDICAL IMAGING 2014; 33:1788-1802. [PMID: 24801649 DOI: 10.1109/tmi.2014.2320602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Flow diversion is an emerging endovascular treatment option for cerebral aneurysms. Quantitative assessment of hemodynamic changes induced by flow diversion can aid clinical decision making in the treatment of cerebral aneurysms. In this article, besides summarizing past key research efforts, we propose a novel metric for the angiographic assessment of flow diverter deployments in the treatment of cerebral aneurysms. By analyzing the frequency spectra of signals derived from digital subtraction angiography (DSA) series, the metric aims to quantify the prevalence of frequency components that correspond to the patient-specific heart rate. Indicating the decoupling of aneurysms from healthy blood circulation, our proposed metric could advance clinical guidelines for treatment success prediction. The very promising results of a retrospective feasibility study on 26 DSA series warrant future efforts to study the validity of the proposed metric within a clinical setting.
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Zanaty M, Chalouhi N, Starke RM, Barros G, Saigh MP, Schwartz EW, Ajiboye N, Tjoumakaris SI, Hasan D, Rosenwasser RH, Jabbour P. Flow Diversion Versus Conventional Treatment for Carotid Cavernous Aneurysms. Stroke 2014; 45:2656-61. [DOI: 10.1161/strokeaha.114.006247] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Mario Zanaty
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Nohra Chalouhi
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Robert M. Starke
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Guilherme Barros
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Mark Philip Saigh
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Eric Winthrop Schwartz
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Norman Ajiboye
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Stavropoula I. Tjoumakaris
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - David Hasan
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Robert H. Rosenwasser
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | - Pascal Jabbour
- From the Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA (M.Z., N.C., G.B., M.P.S., E.W.S., N.A., S.I.T., R.H.R., P.J.); Department of Neurosurgery, University of Virginia, Charlottesville (R.M.S.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
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Ghosh N, Sun Y, Bhanu B, Ashwal S, Obenaus A. Automated detection of brain abnormalities in neonatal hypoxia ischemic injury from MR images. Med Image Anal 2014; 18:1059-69. [PMID: 25000294 DOI: 10.1016/j.media.2014.05.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 04/23/2014] [Accepted: 05/10/2014] [Indexed: 11/30/2022]
Abstract
We compared the efficacy of three automated brain injury detection methods, namely symmetry-integrated region growing (SIRG), hierarchical region splitting (HRS) and modified watershed segmentation (MWS) in human and animal magnetic resonance imaging (MRI) datasets for the detection of hypoxic ischemic injuries (HIIs). Diffusion weighted imaging (DWI, 1.5T) data from neonatal arterial ischemic stroke (AIS) patients, as well as T2-weighted imaging (T2WI, 11.7T, 4.7T) at seven different time-points (1, 4, 7, 10, 17, 24 and 31 days post HII) in rat-pup model of hypoxic ischemic injury were used to assess the temporal efficacy of our computational approaches. Sensitivity, specificity, and similarity were used as performance metrics based on manual ('gold standard') injury detection to quantify comparisons. When compared to the manual gold standard, automated injury location results from SIRG performed the best in 62% of the data, while 29% for HRS and 9% for MWS. Injury severity detection revealed that SIRG performed the best in 67% cases while 33% for HRS. Prior information is required by HRS and MWS, but not by SIRG. However, SIRG is sensitive to parameter-tuning, while HRS and MWS are not. Among these methods, SIRG performs the best in detecting lesion volumes; HRS is the most robust, while MWS lags behind in both respects.
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Affiliation(s)
- Nirmalya Ghosh
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA
| | - Yu Sun
- Center for Research in Intelligent Systems (CRIS), University of California, Riverside, CA 92521, USA
| | - Bir Bhanu
- Center for Research in Intelligent Systems (CRIS), University of California, Riverside, CA 92521, USA
| | - Stephen Ashwal
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA
| | - Andre Obenaus
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, CA 92354, USA; Cell, Molecular and Developmental Biology Program and Department of Neuroscience, University of California, 1140 Bachelor Hall, Riverside, CA 92521, USA.
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Zhou Y, Yang PF, Fang YB, Xu Y, Hong B, Zhao WY, Li Q, Zhao R, Huang QH, Liu JM. Parent artery reconstruction for large or giant cerebral aneurysms using a Tubridge flow diverter (PARAT): study protocol for a multicenter, randomized, controlled clinical trial. BMC Neurol 2014; 14:97. [PMID: 24885396 PMCID: PMC4016793 DOI: 10.1186/1471-2377-14-97] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 04/11/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The treatment of large (10-25 mm) or giant (≥25 mm) cerebral aneurysms remains technically challenging, with a much higher complication and recanalization rate than that is observed for smaller aneurysms. The use of a flow diverter seems to facilitate the treatment of this special entity. In a previous single-center prospective study approved by the Ethics Committee and China Food and Drug Administration (CFDA), we obtained promising results, showing remarkable safety and effectiveness for the Tubridge flow diverter. Nevertheless, the previous study may have been limited by biases due to its single-center design and limited number of subjects. Furthermore, although various articles have reported durable results from treating aneurysms using flow diverters, increasing questions have arisen about this form of treatment. Thus, prospective, multiple-center, randomized trials containing more subjects are needed. METHODS/DESIGN This study is a multicenter, randomized, controlled clinical trial comparing clinical outcomes for patients with unruptured large/giant intracranial aneurysms treated with either conventional stent-assisted coiling or flow diverter implantation. A total of 124 patients who fulfill the inclusion and exclusion criteria will be randomized into either a treatment group or a control group in the ratio of 1:1. The treatment group will receive Tubridge implantation alone or combined with bared coils, and the control group will be treated with stent-assisted coiling (bare coils). The primary endpoint will be the complete occlusion rate at 6-month follow-up. Secondary endpoints include the immediate technique success rate, overall mortality, adverse events (ischemic stroke or intracranial bleeding) within 30 days, 90 days and 1 year post-operation, and the rate of intra-stent stenosis and thrombosis 6 months post-operation. DISCUSSION This prospective trial may provide more information on the safety and efficacy of the Tubridge flow diverter and may potentially change the strategy for treatment of large or giant aneurysms. TRIAL REGISTRATION The trial is registered on the Chinese Clinical Trial Registry: ChiCTR-TRC-13003127.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Qing-Hai Huang
- Department of Neurosurgery, Changhai Hospital, Second Military Medical University, 168 Changhai Road, Shanghai 200433, P,R, China.
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Mut F, Raschi M, Scrivano E, Bleise C, Chudyk J, Ceratto R, Lylyk P, Cebral JR. Association between hemodynamic conditions and occlusion times after flow diversion in cerebral aneurysms. J Neurointerv Surg 2014; 7:286-90. [DOI: 10.1136/neurintsurg-2013-011080] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Larrabide I, Geers AJ, Morales HG, Aguilar ML, Rüfenacht DA. Effect of aneurysm and ICA morphology on hemodynamics before and after flow diverter treatment. J Neurointerv Surg 2014; 7:272-80. [DOI: 10.1136/neurintsurg-2014-011171] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Pereira VM, Ouared R, Brina O, Bonnefous O, Satwiaski J, Aerts H, Ruijters D, van Nijnatten F, Perren F, Bijlenga P, Schaller K, Lovblad KO. Quantification of internal carotid artery flow with digital subtraction angiography: validation of an optical flow approach with Doppler ultrasound. AJNR Am J Neuroradiol 2014; 35:156-63. [PMID: 23928145 PMCID: PMC7966491 DOI: 10.3174/ajnr.a3662] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 03/28/2013] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Digital subtraction angiography is the reference standard technique to evaluate intracranial vascular anatomy and used on the endovascular treatment of vascular diseases. A dedicated optical flow-based algorithm was applied to DSA to measure arterial flow. The first quantification results of internal carotid artery flow validated with Doppler sonography are reported. MATERIALS AND METHODS We included 22 consecutive patients who underwent endovascular procedures. To assess the sensitivity of the algorithm to contrast agent-blood mixing dynamics, we acquired high-frame DSA series (60 images/s) with different injection rates: 1.5 mL/s (n = 19), 2.0 mL/s (n = 18), and 3.0 mL/s (n = 13). 3D rotational angiography was used to extract the centerline of the vessel and the arterial section necessary for volume flow calculation. Optical flow was used to measure flow velocities in straight parts of the ICAs; these data were further compared with Doppler sonography data. DSA mean flow rates were linearly regressed on Doppler sonography measurements, and regression slope coefficient bias from value 1 was analyzed within the 95% confidence interval. RESULTS DSA mean flow rates measured with the optical flow approach significantly matched Doppler sonography measurements (slope regression coefficient, b = 0.83 ± 0.19, P = .05) for injection rate = 2.0 mL/s and circulating volumetric blood flow <6 mL/s. For injection rate = 1.5 mL/s, volumetric blood flow <3 mL/s correlated well with Doppler sonography (b = 0.67 ± 0.33, P = .05). Injection rate = 3.0 mL/s failed to provide DSA-optical flow measurements correlating with Doppler sonography because of the lack of measurable pulsatility. CONCLUSIONS A new model-free optical flow technique was tested reliably on the ICA. DSA-based blood flow velocity measurements were essentially validated with Doppler sonography whenever the conditions of measurable pulsatility were achieved (injection rates = 1.5 and 2.0 mL/s).
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Giorgianni A, Pellegrino C, Minotto R, Mercuri A, Frattini L, Baruzzi F, Valvassori L. Flow-Diverter Stenting of Post-Traumatic Bilateral Anterior Cerebral Artery Pseudoaneurysm. Interv Neuroradiol 2014. [DOI: 10.15274/inr-2014-10100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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De Vries J, Boogaarts J, Van Norden A, Wakhloo AK. New Generation of Flow Diverter (Surpass) for Unruptured Intracranial Aneurysms. Stroke 2013; 44:1567-77. [PMID: 23686973 DOI: 10.1161/strokeaha.111.000434] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
In patients harboring intracranial aneurysms, the major goal in treatment is to prevent bleeding. A new generation of an endoluminal device (Surpass Flow Diverter [Surpass]) was developed to reconstruct parent artery and occlude the aneurysm. We present our clinical and angiographic single-center experience.
Methods—
Patients with a wide range of complex unruptured aneurysms were treated with the Surpass placed in the parent artery and bridging the aneurysm. Clinical and angiographic follow-up were performed at 6 months. Data were prospectively collected.
Results—
Thirty seven patients (mean age, 56 years; range, 32–79), harboring 49 unruptured aneurysms were treated at our center. All except 1 patient were treated with a single device. Successful delivery of the device was achieved in all patients. All 35 nonbifurcation aneurysm necks were covered completely, whereas 14 bifurcation aneurysms were only partially covered. There was no major periprocedural morbidity or mortality. During follow-up, 4 patients (10.4%) experienced transient neurological deficit. One patient (3%) developed a minor stroke at 4-month follow-up with persistent neurological deficit. Twelve patients had neurological symptoms related to their aneurysm and 7 showed improvement of these symptoms during follow-up. At 6-month follow-up, 29 of 31 aneurysms studied that had complete neck coverage showed a complete occlusion (94%) including 1 case with a 95% to 100% occlusion, whereas 5 of the 10 bifurcation aneurysms were occluded.
Conclusions—
Our study shows high safety and efficacy profile of a new generation endoluminal device in treatment of complex intracranial aneurysms. Long-term studies of treated bifurcation aneurysms are needed.
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Affiliation(s)
- Joost De Vries
- From the Departments of Neurosurgery (J.D.V., J.B.) and Neurology (A.V.N.), Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands; and Department of Radiology (A.K.W.), University of Massachusetts Medical School, Worcester, MA
| | - Jeroen Boogaarts
- From the Departments of Neurosurgery (J.D.V., J.B.) and Neurology (A.V.N.), Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands; and Department of Radiology (A.K.W.), University of Massachusetts Medical School, Worcester, MA
| | - Anouk Van Norden
- From the Departments of Neurosurgery (J.D.V., J.B.) and Neurology (A.V.N.), Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands; and Department of Radiology (A.K.W.), University of Massachusetts Medical School, Worcester, MA
| | - Ajay K. Wakhloo
- From the Departments of Neurosurgery (J.D.V., J.B.) and Neurology (A.V.N.), Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands; and Department of Radiology (A.K.W.), University of Massachusetts Medical School, Worcester, MA
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Trager AL, Sadasivan C, Lieber BB. Comparison of the in vitro hemodynamic performance of new flow diverters for bypass of brain aneurysms. J Biomech Eng 2013; 134:084505. [PMID: 22938365 DOI: 10.1115/1.4006454] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
One possible treatment for cerebral aneurysms is a porous tubular structure, similar to a stent, called a flow diverter. A flow diverter can be placed across the neck of a cerebral aneurysm to induce the cessation of flow and initiate the formation of an intra-aneurysmal thrombus. This excludes the aneurysm from the parent artery and returns the flow of blood to normal. Previous flow diverting devices have been analyzed to determine optimal characteristics, such as braiding angle and wire diameter. From this information, a new optimized device was designed to achieve equivalent hemodynamic performance to the previous best device, but with better longitudinal flexibility to preserve physiological arterial configuration. The new device was tested in vitro in an elastomeric replica of the rabbit elastase induced aneurysm model and is now in the process of being tested in vivo. Particle image velocimetry was utilized to determine the velocity field in the plane of symmetry of the model under pulsatile flow conditions. Device hemodynamic performance indices such as the hydrodynamic circulation were evaluated from the velocity fields. Comparison of these indices with the previous best device and a control shows that the significant design changes of the device did not change its hemodynamic attributes (p > 0.05).
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Affiliation(s)
- Asher L Trager
- Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA
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Chitale R, Gonzalez LF, Randazzo C, Dumont AS, Tjoumakaris S, Rosenwasser R, Chalouhi N, Gordon D, Jabbour P. Single center experience with pipeline stent: feasibility, technique, and complications. Neurosurgery 2013; 71:679-91; discussion 691. [PMID: 22653389 DOI: 10.1227/neu.0b013e318260fe86] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Endovascular coil embolization is an established method of treatment for intracranial aneurysms. The pipeline embolization device (PED) is a low-porosity endovascular stent designed to reconstruct the parent artery and decrease blood flow into the aneurysm. OBJECTIVE To report a series of 36 patients treated with the PED. METHODS Thirty-six patients underwent PED placement for aneurysm at the Jefferson Hospital for Neuroscience from October 2010 to November 2011. Clinical charts were reviewed. RESULTS Thirty-six patients with 42 aneurysms were treated (3 male; 33 female; ages, 34-82; mean age, 60.1 years). Forty-one aneurysms were located in the anterior circulation, whereas one was located at the vertebrobasilar junction. PED placement was successful in all patients and resulted in stasis within all treated aneurysms. Symptomatic postoperative complications were witnessed in 13.9% (n = 5) of patients. These complications included intracerebral hemorrhage (n = 4), dissection (n = 1), symptomatic stroke (n = 2), and death (n = 1). CONCLUSION Treatment of simple or complex intracranial aneurysms with PEDs alone or in conjunction with coil embolization is technically feasible, and the deployment technique requires a high degree of endovascular skills. Major perioperative adverse events must be studied. Respect for the indications of the procedure is crucial to justify the risk.
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Affiliation(s)
- Rohan Chitale
- Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA
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Lanzino G, Crobeddu E, Cloft HJ, Hanel R, Kallmes DF. Efficacy and safety of flow diversion for paraclinoid aneurysms: a matched-pair analysis compared with standard endovascular approaches. AJNR Am J Neuroradiol 2012; 33:2158-61. [PMID: 22790243 DOI: 10.3174/ajnr.a3207] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Flow diversion is a new strategy for the treatment of complex paraclinoid aneurysms. However, flow diverters have, to date, not been tested in direct comparison with other available treatments. We present a matched-pair comparison of paraclinoid aneurysms treated with the PED versus other endovascular techniques. MATERIALS AND METHODS Twenty-one eligible patients with 22 paraclinoid aneurysms treated with the PED at our institution were matched with historic controls with aneurysms of similar size and location. RESULTS There were no statistically significant differences between the 2 groups in terms of aneurysm size, location, risk factors, or comorbidities. Mean dome size was 13.9 ± 6.7 mm in the control group and 14.9 ± 6.3 mm in the PED group (P = .52). Balloon and stent assistance were used in 31.8% and 9.1% of controls, respectively, while carotid sacrifice was used in 36.4% of the controls. There was a significant difference in the rate of complete occlusion favoring PED at radiologic follow-up (P = .03). CONCLUSIONS Flow diverters achieve a much higher rate of complete angiographic obliteration compared with other standard endovascular techniques in the treatment of internal carotid artery aneurysms. In this series, this higher angiographic obliteration rate did not occur at the expense of an increased rate of complications. Careful long-term follow-up is of the utmost importance to definitively validate flow diversion as a superior therapeutic strategy for proximal internal carotid artery aneurysms.
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Affiliation(s)
- G Lanzino
- Departments of Neurosurgery, Mayo Clinic, Rochester, MN 55905, USA.
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Tse MMY, Yan B, Dowling RJ, Mitchell PJ. Current status of pipeline embolization device in the treatment of intracranial aneurysms: a review. World Neurosurg 2012; 80:829-35. [PMID: 23041067 DOI: 10.1016/j.wneu.2012.09.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 08/14/2012] [Accepted: 09/27/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Pipeline embolization device (PED) implantation is a novel endovascular treatment option for the treatment of intracranial aneurysms. It is emerging as a useful alternative to coiling and to open surgery, and its use is increasing worldwide. We performed a literature review to examine its efficacy, technical challenges, and safety. METHODS PubMed database was used to identify all articles relating to PED. RESULTS The review outlines the indications for PED, its technical aspects, complications, and clinical outcomes. CONCLUSIONS PED offers an alternative to endovascular coiling for aneurysms with complex morphology. The indication for its use has evolved from the limited scope of treatment of giant aneurysms with wide necks to the inclusion of smaller aneurysms. The procedural safety profile of PED is comparable with or possibly superior to balloon-remodeling or stent-assisted coil embolization in specific circumstances. However, questions remain regarding the incidence of post-procedural subarachnoid hemorrhage. Ongoing monitoring and meticulous documentation of PED postimplantation safety is strongly recommended.
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Affiliation(s)
- Mona M Y Tse
- Neurointervention Service, Department of Radiology, Royal Melbourne Hospital, Melbourne, Victoria, Australia.
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Larrabide I, Aguilar ML, Morales HG, Geers AJ, Kulcsár Z, Rüfenacht D, Frangi AF. Intra-aneurysmal pressure and flow changes induced by flow diverters: relation to aneurysm size and shape. AJNR Am J Neuroradiol 2012; 34:816-22. [PMID: 23019173 DOI: 10.3174/ajnr.a3288] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Effects of blood flow modification by flow diverters are observed to lead often to aneurysm thrombosis and reverse remodeling. For this process, to further understand the potential roles of intra-aneurysmal blood pressure changes and aneurysm morphologies, 23 patients were studied by numeric simulation. MATERIALS AND METHODS 3D imaging of aneurysms of different sizes and shapes, all located at the supraclinoid segment of the ICA (n=23), was prepared for CFD simulations. Hemodynamic variables were calculated for conditions before and after virtual FD implantation, reconstituting a vessel wall scaffold across the aneurysm neck. WSS, velocity, residence time, turnover time, and intra-aneurysmal pressure were assessed statistically. RESULTS After placement of FDs, significant reductions inside the aneurysm were observed for most hemodynamic variables (P<.01) except mean intra-aneurysmal pressures. For minimum/maximum intra-aneurysmal pressure values, small but significant changes were found; however, they were considered too small to be of relevance. CONCLUSIONS Calculations in 23 cases did not reveal significant intra-aneurysmal mean or peak pressure changes, indicating a minor role of pressure changes in the rare event of secondary ruptures after FD use. Other hemodynamic variables (WSS and velocity) exhibited more significant changes, indicating their role in intra-aneurysmal thrombus formation. Size-dependent, significantly higher reduction in WSS (P=.069) and velocity (P=.013) was observed in small aneurysms compared with larger ones. When it came to shape, there were significantly higher reductions in WSS (P=.055) and velocity (P=.065) and a significantly higher increase in turnover time in fusiform aneurysms compared with saccular aneurysms.
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Affiliation(s)
- I Larrabide
- Networking Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine, Barcelona, Spain.
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Measurement of quantifiable parameters by time-density curves in the elastase-induced aneurysm model: first results in the comparison of a flow diverter and a conventional aneurysm stent. Eur Radiol 2012; 23:521-7. [PMID: 22895618 DOI: 10.1007/s00330-012-2611-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 07/01/2012] [Accepted: 07/13/2012] [Indexed: 10/28/2022]
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Simple measurement of aneurysm residual after treatment: the SMART scale for evaluation of intracranial aneurysms treated with flow diverters. Acta Neurochir (Wien) 2012; 154:21-6; discussion 26. [PMID: 22002552 DOI: 10.1007/s00701-011-1177-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 09/20/2011] [Indexed: 10/16/2022]
Abstract
BACKGROUND Primary endovascular reconstruction with flow diversion represents a fundamental paradigm shift in the technique of endovascular aneurysm treatment. Unlike coil embolization, often there remains residual post-procedural filling within the aneurysm with flow diverters, the curative reconstruction presumably occurring over a period of weeks. Thus, conventional grading scales for post-procedural aneurysm occlusion and recanalization are inadequate. The aim of this paper is to propose a new angiographic grading scale that addresses this fundamentally new treatment option. METHOD A five-point grading scale describes the location of residual flow within the aneurysm in the venous phase [grade 1: patent aneurysm with diffuse inflow; grade 2: residual filling of the aneurysm dome (saccular) or wall (fusiform); grade 3: only residual neck (saccular) or only intra-aneurysmal filling with former boundaries covered (fusiform); grade 4: complete occlusion]. FINDINGS Grade 0 represents any aneurysm, regardless of occlusion rate with early phase, coherent inflow jet. Intra-aneurysmal flow stagnation is categorized into: (a) none, (b) capillary phase, and (c) venous phase. Prevailing parent vessel hemodynamics with in-stent stenosis (ISS) are divided into none (ISS0), mild (ISS1), moderate (ISS2), severe (ISS3), and total (ISS4) occlusion. The proposed grading scales allow assessment of the hemodynamic consequences of stent placement on endosaccular in-flow, stasis, and location of stasis as well as parent vessel hemodynamics. CONCLUSIONS Further studies need to show the applicability and possible predictive value of this new grading scale on the efficacy of the stent in promoting intra-aneurysmal flow stagnation, thus creating the potential to harmonize the results of future papers. This may help to optimize treatment and future device design.
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Effects of metal coverage rate of flow diversion device on neointimal growth at side branch ostium and stented artery: an animal experiment in rabbit abdominal aorta. Neuroradiology 2011; 54:849-55. [PMID: 22170078 DOI: 10.1007/s00234-011-0984-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2011] [Accepted: 11/21/2011] [Indexed: 10/14/2022]
Abstract
INTRODUCTION To access the effect of actual metal coverage rate (MCR) on neointimal growth at covered side branch ostium and stented artery after implantation of a flow diversion device. METHODS Flow diverters (FDs) were implanted into abdominal aortas of 20 New Zealand rabbits. Four weeks and three months after FD implantation, the patency of side branches covered by the devices was assessed by angiography. The animals were sacrificed after angiography at 3 months postsurgery. The local actual MCR was measured under microscope and calculated. The extent of neointimal coverage at the ostia of branches and the neointima within the stent were examined by histology and scanning electron microscopy. RESULTS No side branch occlusion was noted, either immediately after implantation or at follow-ups. At 3 months after implantation, the intimal coverage of branch ostia caused by a 30-40% MCR was not significantly different from that caused by an MCR ≤ 30% (p = 0.792), but it was significantly lower than that caused by an MCR ≥ 40% (p = 0.021). Neointimal thickness in the stented abdominal aorta was positively correlated to MCR (r = 0.523, p = 0.001). The neointima was composed predominantly of smooth muscle cells and collagen fibers. CONCLUSION The actual MCR exhibited remarkable differences once FD was implanted in vivo. Significantly more intimal coverage at the side branch ostia could be induced when MCR was ≥40%. The neointimal thickness within the stent was positively correlated to device MCR.
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Correlation of aneurysm occlusion with actual metal coverage at neck after implantation of flow-diverting stent in rabbit models. Neuroradiology 2011; 54:607-13. [DOI: 10.1007/s00234-011-0922-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Accepted: 07/15/2011] [Indexed: 10/17/2022]
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Abstract
The introduction of flow diverters for treatment of intracranial aneurysms represents a major paradigm shift in the treatment of these lesions. The theoretical hallmark of flow diverters is the treatment of the diseased segment harboring the aneurysm instead of treating the aneurysm itself. Flow diverters are designed to induce disruption of flow near the aneurysm neck while preserving flow into parent vessel and adjacent branches. After flow diversion, intra-aneurysmal thrombosis occurs, followed by shrinkage of the aneurysmal sac as the thrombus organizes and retracts. Preliminary clinical series document effective treatment of wide-neck and/or large and giant aneurysms with acceptable complication rates. However, several questions remain unanswered related to the incidence and mechanisms of aneurysm rupture after treatment with flow diverters, fate of small perforating vessels, and long-term patency rates.
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Affiliation(s)
- Pietro I. D'Urso
- From the Department of Neurosurgery (P.I.D., G.L.) and Department of Radiology (H.J.C., D.F.K.), Mayo Clinic, Rochester, MN
| | - Giuseppe Lanzino
- From the Department of Neurosurgery (P.I.D., G.L.) and Department of Radiology (H.J.C., D.F.K.), Mayo Clinic, Rochester, MN
| | - Harry J. Cloft
- From the Department of Neurosurgery (P.I.D., G.L.) and Department of Radiology (H.J.C., D.F.K.), Mayo Clinic, Rochester, MN
| | - David F. Kallmes
- From the Department of Neurosurgery (P.I.D., G.L.) and Department of Radiology (H.J.C., D.F.K.), Mayo Clinic, Rochester, MN
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Ionita CN, Natarajan SK, Wang W, Hopkins LN, Levy EI, Siddiqui AH, Bednarek DR, Rudin S. Evaluation of a second-generation self-expanding variable-porosity flow diverter in a rabbit elastase aneurysm model. AJNR Am J Neuroradiol 2011; 32:1399-407. [PMID: 21757527 DOI: 10.3174/ajnr.a2548] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The self-expanding V-POD is a second-generation flow-diverting device with a low-porosity PTFE patch on a self-expanding microstent. The authors evaluated this device for the treatment of elastase-induced aneurysms in rabbits. MATERIALS AND METHODS Three V-POD types (A, circumferential patch closed-cell stent [n = 9]; B, asymmetric patch closed-cell stent [n = 7]; and C, asymmetric patch open-cell stent [n = 4]) were evaluated by using angiography, conebeam micro-CT, histology, and SEM. Aneurysm flow modifications were expressed in terms of immediate poststent/prestent ratios of maximum CA volume entering the aneurysm dome tracked on procedural angiograms. Flow modifications were correlated with 4 weeks' follow-up angiographic, micro-CT, histologic, and SEM results. RESULTS Mechanical stent-deployment difficulties in 4 aneurysms (1 type A; 3 type B) led to suboptimal results and exclusion from analysis. Of the remaining 16 aneurysms, 4-week post-treatment angiograms showed no aneurysm filling in 10 (63%), 3 (∼19%) had no filling with a small remnant neck, and 3 (∼19%) had <0.25 filling. Successfully treated aneurysms (n = 16) demonstrated an immediate poststent/prestent CA maximum volume ratio of 0.13 ± 0.18% (0.0%-0.5%). Favorable contrast-flow modification on immediate angiography after deployment correlated significantly with aneurysm occlusion on follow-up angiography, micro-CT, and histology. The occlusion percentage derived from micro-CT was 96 ± 6.8%. Histology indicated advanced healing (grade ≥3) in the aneurysm dome in 13 of 16 cases. SEM revealed 15 of 16 stents in an advanced state of endothelialization. CONCLUSIONS This study showed the feasibility and effectiveness of V-POD for aneurysm healing in a rabbit elastase model.
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Affiliation(s)
- C N Ionita
- Department of Radiology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA
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