1.MR vessel wall imaging for predicting instability status of intracranial aneurysm
Xinmei MA ; Qichang FU ; Shanshan XIE ; Yong ZHANG ; Jingliang CHENG ; Sheng GUAN
Chinese Journal of Medical Imaging Technology 2025;41(1):15-19
Objective To observe the value of MR vessel wall imaging(VMI)for predicting instability status of intracranial aneurysm(IA).Methods MR angiography(MRA)and vascular wall imaging(VWI)data of 506 patients with single IA were retrospectively analyzed.Asymptomatic IA was included in stable status group(n=349),while those with enlargement during follow-up or threatened rupture symptoms were taken as instable status group(n=157).The patients were divided into training set(n=354)and validation set(n=152)at a ratio of 7:3.The least absolute shrinkage and selection operator(LASSO)and multivariate logistic regression were performed to screen risk factors associated with IA instability based on clinical data,MRA and VWI manifestations.Then model 1 was constructed based the above indexes,while model 2 was established based only on MRA manifestations of IA.The receiver operating characteristic curve was plotted,and the area under the curve(AUC)was calculated to evaluate the efficacy of each model for predicting IA instability.Results LASSO and multivariate logistic regression showed that female patient,age<50 years with history of cerebral infarction and IA wall enhancement on MRA were all independent predictors of IA instability status.The AUC of model 1 for predicting instability status of IA was 0.733 and 0.742 in training set and validation set,respectively,both higher than that of model 2(0.593 and 0.609,both P<0.05).Conclusion MR VWI was helpful for predicting IA instability status.
2.MR vessel wall imaging for predicting instability status of intracranial aneurysm
Xinmei MA ; Qichang FU ; Shanshan XIE ; Yong ZHANG ; Jingliang CHENG ; Sheng GUAN
Chinese Journal of Medical Imaging Technology 2025;41(1):15-19
Objective To observe the value of MR vessel wall imaging(VMI)for predicting instability status of intracranial aneurysm(IA).Methods MR angiography(MRA)and vascular wall imaging(VWI)data of 506 patients with single IA were retrospectively analyzed.Asymptomatic IA was included in stable status group(n=349),while those with enlargement during follow-up or threatened rupture symptoms were taken as instable status group(n=157).The patients were divided into training set(n=354)and validation set(n=152)at a ratio of 7:3.The least absolute shrinkage and selection operator(LASSO)and multivariate logistic regression were performed to screen risk factors associated with IA instability based on clinical data,MRA and VWI manifestations.Then model 1 was constructed based the above indexes,while model 2 was established based only on MRA manifestations of IA.The receiver operating characteristic curve was plotted,and the area under the curve(AUC)was calculated to evaluate the efficacy of each model for predicting IA instability.Results LASSO and multivariate logistic regression showed that female patient,age<50 years with history of cerebral infarction and IA wall enhancement on MRA were all independent predictors of IA instability status.The AUC of model 1 for predicting instability status of IA was 0.733 and 0.742 in training set and validation set,respectively,both higher than that of model 2(0.593 and 0.609,both P<0.05).Conclusion MR VWI was helpful for predicting IA instability status.
3.Flow diverter alone versus flow diverter combined with adjunctive spring coils in the treatment of intracranial large or giant aneurysms:comparison of the safety and efficacy
Mengsi AN ; Yajing MA ; Yuanzhi LI ; Wulin MA ; Sheng GUAN ; Xinbin GUO
Journal of Interventional Radiology 2025;34(12):1300-1305
Objective To compare the safety and efficacy of flow diverter with adjunctive spring coils(FAC)and simple flow diverter(FD)in the treatment of large or giant intracranial aneurysms.Methods The clinical data of 48 patients with large or giant intracranial aneurysm(55 intracranial aneurysms in total),who were treated at the First Affiliated Hospital of Zhengzhou University of China from January 2018 to September 2023,were retrospectively analyzed.According to the treatment method,the patients were divided into pure FD group and FAC group.The aneurysm occlusion rate and the incidence of procedure-related complications were compared between the two groups.Univariate and multivariate logistic regression analyses were used to identify risk factors for procedure-related complications.Results A total of 55 intracranial aneurysms detected in the 48 patients were included in this study.The median maximum diameter of aneurysms was 20.25 mm(16.45,24.62 mm).Among them,12 aneurysms were treated with FD alone,and 43 aneurysms were treated with FAC.The median follow-up time was 6.63 months(5.88,8.07 months).Compared with pure FD group,in FAC group the occlusion rate of aneurysms was significantly higher(86.1%vs.50.0%,P=0.023),while there was no statistically significant difference in the incidence of procedure-related complications between the two groups(18.18%vs.16.67%,P=1.000).Multivariate logistic regression analysis showed that the use of more than one stent(OR=6.63,95%CI=1.10-39.88,P=0.039)and the difference between the distal parent artery diameter and the stent diameter(Dd)(OR=7.00,95%CI=1.4-35.7,P=0.019)were the independent risk factors for procedure-related complications.The area under the receiver operating characteristic curve(AUC)of the receiver operating characteristic curve(ROC)for distal parent artery Dd was 0.854(95%CI=0.746-0.963).Conclusion For the treatment of large or giant intracranial aneurysms,FAC is clinically safe and effective.The mid-term follow-up aneurysm occlusion rate of FAC is higher than that of simple FD treatment.The use of more than one stent and the distal parent artery Dd are the independent risk factors for procedure-related complications in the treatment of large or giant intracranial aneurysms with FD.
4.Safety and efficacy of intrasaccular flow disruptor in intracranial aneurysms
Jifa LIU ; Yuanzhi LI ; Feng FAN ; Hang ZHANG ; Nan MA ; Zhen WANG ; Sheng GUAN
Chinese Journal of Neuromedicine 2025;24(3):230-234
Objective:To explore the safety and efficacy of intrasaccular flow disruptor in intracranial aneurysms, including wide-necked aneurysms.Methods:A retrospective analysis was performed; 102 patients with intracranial aneurysms treated with intrasaccular flow disruptor at Department of Neurointervention, First Affiliated Hospital of Zhengzhou University from August 2022 to November 2024 were enrolled; their clinical and imaging data were collected. The aneurysm characteristics and perioperative complications were summarized; aneurysm occlusion was evaluated by Woven EndoBridge occlusion scale (WOS) immediately after surgery and during the follow-up period.Results:Among the 102 aneurysms, 33 were anterior cerebral artery aneurysms, 40 were middle cerebral artery aneurysms, 17 were internal carotid artery aneurysms and 12 were basilar artery aneurysms; 73 aneurysms were regular intracranial saccular aneurysms and 29 were irregular saccular ones (17 of them with daughter sacs); 12 aneurysms were ruptured at acute phase. The surgical success rate was 100%: single intrasaccular flow disruptor was implanted into 95 patients, and stent-assisted or salvage treatments were given to 7 patients). Immediately after surgery, WOS grading A was noted in 5 patients, grading B in 7, grading C in 31, and grading D in 59. Two patients suffered severe perioperative complications and passed away: one patient died for ischemic complications that ensued after stent salvage treatment (parent artery being compressed by intrasaccular flow disruptor); the other patient died for hemorrhagic complications triggered by rupture of an initially unruptured aneurysm following intrasaccular flow disruptor implantation. Among them, 52 patients completed postoperative DSA follow-up, with a median follow-up of 205 (168, 292) days; WOS grading A was noted in 31 patients, grading B in 9, grading C in 8, and grading D in 4 at the last follow-up; the full occlusion rate was 92.3%, and no ischemic or hemorrhagic adverse events occurred.Conclusion:Intrasaccular flow disruptor shows high short-term safety and good efficacy in the treatment of intracranial aneurysms.
5.Efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms: a multicenter retrospective study
Xiaowen ZHANG ; Jing LI ; Xifeng LI ; Chuanzhi DUAN ; Aihua LIU ; Huaizhang SHI ; Haowen XU ; Nan MA ; Zhiqiang YAO ; Feng FAN ; Chao LIU ; Jinyi LI ; Hailong ZHONG ; Mengyan FAN ; Jiaxin WAN ; Rijin LIN ; Huixiang LIU ; Jiamei ZHANG ; Xin ZHANG ; Sheng GUAN
Chinese Journal of Neuromedicine 2025;24(1):16-22
Objective:To evaluate the efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms.Methods:One hundred and seventeen patients with wide-necked intracranial aneurysms treated with intrasaccular flow disruptor were collected from Department of Neurointervention (First Affiliated Hospital of Zhengzhou University), Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University), Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital, Southern Medical University), and Department of Neurosurgery (First Affiliated Hospital of Harbin Medical University) from August 2022 to March 2024. Raymond-Roy Occlusion Classification (RROC) was employed to evaluate aneurysm embolization immediately after procedure; cranial CT or MRI within 48 hours of embolization were performed to identify any new intracranial hemorrhage, subarachnoid hemorrhage, or new symptomatic cerebral infarction related to the intracranial aneurysms. Modified Rankin Scale (mRS) was used to assess the neurological function at discharge. Imaging follow-up and outpatient follow-up were performed at 6 months after embolization to evaluate the aneurysm occlusion degree and complications.Results:A total of 117 intrasaccular flow disruptors were implanted in 117 patients, with a technical success rate of 100%; 115 patients (98.3%) enjoyed successful one-time release of their disruptors, and 2 patients (1.7%) required retrieval and redirection of the disruptors before second successful attempt. Flow disruptor plus stent was performed in 13 patients (11.1%). Immediately after procedure, RROC grading I was noted in 3 patients, grading II in 51 patients and grading III in 63 patients. Cranial CT or MRI within 48 hours of embolization indicated no new intracranial hemorrhage, subarachnoid hemorrhage, or symptomatic cerebral infarction related to the intracranial aneurysms. All patients had mRS score of 0 at discharge. Eighty-three patients completed a 6-month follow-up (RROC grading I in 41 patients, grading II in 33 patients and grading III in 9 patients), without ischemic or hemorrhagic adverse events.Conclusion:The results of this study preliminarily suggest that intrasaccular flow disruptor is effective and safe in wide-necked intracranial aneurysms.
6.Impact of flow diverter malapposition at the aneurysm neck on clinical outcomes and complications of intracranial aneurysms
Jie YANG ; Shuhai LONG ; Shuailong SHI ; Yukun HOU ; Ji MA ; Ye WANG ; Sheng GUAN ; Tengfei LI
Chinese Journal of Neuromedicine 2025;24(6):599-608
Objective:To investigate the impact of flow diverter (FD) malapposition at the aneurysm neck on clinical outcomes and complications of intracranial aneurysms, and identify the influencing factors for intraoperative FD malapposition.Methods:A retrospective study was performed; 153 patients with unruptured saccular aneurysms at the C4-C7 segments of the internal carotid artery accepted single FD implantation at Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from June 2022 to March 2024 were chosen. Intraoperative high-resolution C-arm CT was utilized to assess FD apposition at the aneurysm neck. (1) Based on FD apposition at the aneurysm neck as shown, these 153 patients were divided into a malapposition group ( n=23, including 16 patients with malapposition being identified as residual malapposition after intraoperative corrective measures such as microwire massage and 7 patients with malapposition being newly detected in this study) and a complete apposition group ( n=130). Perioperative and follow-up complications were recorded. Clinical outcomes were assessed using modified Rankin Scale (mRS) at the final follow-up (mRS score of 0-2 as favorable outcome), and angiographic outcomes were evaluated by DSA at the final follow-up. Differences in clinical and angiographic outcomes and complication rate were compared between the malapposition group and complete apposition group. (2) Based on FD apposition at the aneurysm neck as shown, these 153 patients were divided into an intraoperative malapposition group ( n=74, including 67 patients with malapposition being detected during surgery and 7 patients with malapposition being newly detected in this study) and an intraoperative complete apposition group ( n=79). Univariate analysis was performed to compare the clinical variables between the intraoperative malapposition group and intraoperative complete apposition group; multivariate Logistic regression was further employed to identify the independent influencing factors for FD malapposition at the aneurysm neck. Results:(1) Four patients (all from the malapposition group) developed perioperative acute in-stent thrombosis. Nine patients experienced ischemic or hemorrhagic stroke during the follow-up, including 6 from the malapposition group and 3 from the complete apposition group; the complication rate in the malapposition group (6/23, 26.1%) was significantly higher than that in the complete apposition group (3/130, 2.3%) during the follow-up ( P<0.05). At the final follow-up, 2 patients (both from the malapposition group) had poor clinical outcome, while the remaining 151 patients had favorable outcome. Proportion of patients with favorable outcome between the two groups was statistically different (91.3%[21/23] vs. 100.0%[130/130], P<0.05). Delayed occlusion was detected in 46 patients (12 from the malapposition group and 34 from the complete apposition group) at the final angiographic follow-up. FD restenosis/re-occlusion was noted in 10 patients, including 6 from the malapposition group and 4 from the complete apposition group. Significant difference in delayed occlusion rate (52.2%[12/23] vs. 26.2%[34/130]) and long-term in-stent stenosis/occlusion rate (26.1%[6/23] vs. 3.1%[4/130]) was observed between the two groups ( P<0.05). (2) Significant difference in aneurysm neck diameter, FD angulation, parent artery stenosis, parent artery diameter ratio>1.2, and presence of branching vessels at the FD implantation site was noted between the intraoperative complete apposition group and intraoperative malapposition group ( P<0.05). Multivariate Logistic regression indicated that aneurysm neck diameter ( OR=1.431, 95% CI: 1.096-1.868, P=0.008), parent artery diameter ratio>1.2 ( OR=2.199, 95% CI: 1.083-4.463, P=0.029), and FD angulation ( OR=1.019, 95% CI: 1.002-1.036, P=0.027) were independent influencing factors for FD malapposition at the aneurysm neck. Conclusion:In FD implantation for intracranial aneurysms, FD malapposition at the aneurysm neck adversely affects delayed occlusion rate and complication rate; aneurysms with wider aneurysm neck diameter, parent artery diameter ratio>1.2, and greater FD angulation are trend to have FD malapposition at the aneurysm neck.
7.Safety and efficacy of intrasaccular flow disruptor in intracranial aneurysms
Jifa LIU ; Yuanzhi LI ; Feng FAN ; Hang ZHANG ; Nan MA ; Zhen WANG ; Sheng GUAN
Chinese Journal of Neuromedicine 2025;24(3):230-234
Objective:To explore the safety and efficacy of intrasaccular flow disruptor in intracranial aneurysms, including wide-necked aneurysms.Methods:A retrospective analysis was performed; 102 patients with intracranial aneurysms treated with intrasaccular flow disruptor at Department of Neurointervention, First Affiliated Hospital of Zhengzhou University from August 2022 to November 2024 were enrolled; their clinical and imaging data were collected. The aneurysm characteristics and perioperative complications were summarized; aneurysm occlusion was evaluated by Woven EndoBridge occlusion scale (WOS) immediately after surgery and during the follow-up period.Results:Among the 102 aneurysms, 33 were anterior cerebral artery aneurysms, 40 were middle cerebral artery aneurysms, 17 were internal carotid artery aneurysms and 12 were basilar artery aneurysms; 73 aneurysms were regular intracranial saccular aneurysms and 29 were irregular saccular ones (17 of them with daughter sacs); 12 aneurysms were ruptured at acute phase. The surgical success rate was 100%: single intrasaccular flow disruptor was implanted into 95 patients, and stent-assisted or salvage treatments were given to 7 patients). Immediately after surgery, WOS grading A was noted in 5 patients, grading B in 7, grading C in 31, and grading D in 59. Two patients suffered severe perioperative complications and passed away: one patient died for ischemic complications that ensued after stent salvage treatment (parent artery being compressed by intrasaccular flow disruptor); the other patient died for hemorrhagic complications triggered by rupture of an initially unruptured aneurysm following intrasaccular flow disruptor implantation. Among them, 52 patients completed postoperative DSA follow-up, with a median follow-up of 205 (168, 292) days; WOS grading A was noted in 31 patients, grading B in 9, grading C in 8, and grading D in 4 at the last follow-up; the full occlusion rate was 92.3%, and no ischemic or hemorrhagic adverse events occurred.Conclusion:Intrasaccular flow disruptor shows high short-term safety and good efficacy in the treatment of intracranial aneurysms.
8.Efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms: a multicenter retrospective study
Xiaowen ZHANG ; Jing LI ; Xifeng LI ; Chuanzhi DUAN ; Aihua LIU ; Huaizhang SHI ; Haowen XU ; Nan MA ; Zhiqiang YAO ; Feng FAN ; Chao LIU ; Jinyi LI ; Hailong ZHONG ; Mengyan FAN ; Jiaxin WAN ; Rijin LIN ; Huixiang LIU ; Jiamei ZHANG ; Xin ZHANG ; Sheng GUAN
Chinese Journal of Neuromedicine 2025;24(1):16-22
Objective:To evaluate the efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms.Methods:One hundred and seventeen patients with wide-necked intracranial aneurysms treated with intrasaccular flow disruptor were collected from Department of Neurointervention (First Affiliated Hospital of Zhengzhou University), Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University), Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital, Southern Medical University), and Department of Neurosurgery (First Affiliated Hospital of Harbin Medical University) from August 2022 to March 2024. Raymond-Roy Occlusion Classification (RROC) was employed to evaluate aneurysm embolization immediately after procedure; cranial CT or MRI within 48 hours of embolization were performed to identify any new intracranial hemorrhage, subarachnoid hemorrhage, or new symptomatic cerebral infarction related to the intracranial aneurysms. Modified Rankin Scale (mRS) was used to assess the neurological function at discharge. Imaging follow-up and outpatient follow-up were performed at 6 months after embolization to evaluate the aneurysm occlusion degree and complications.Results:A total of 117 intrasaccular flow disruptors were implanted in 117 patients, with a technical success rate of 100%; 115 patients (98.3%) enjoyed successful one-time release of their disruptors, and 2 patients (1.7%) required retrieval and redirection of the disruptors before second successful attempt. Flow disruptor plus stent was performed in 13 patients (11.1%). Immediately after procedure, RROC grading I was noted in 3 patients, grading II in 51 patients and grading III in 63 patients. Cranial CT or MRI within 48 hours of embolization indicated no new intracranial hemorrhage, subarachnoid hemorrhage, or symptomatic cerebral infarction related to the intracranial aneurysms. All patients had mRS score of 0 at discharge. Eighty-three patients completed a 6-month follow-up (RROC grading I in 41 patients, grading II in 33 patients and grading III in 9 patients), without ischemic or hemorrhagic adverse events.Conclusion:The results of this study preliminarily suggest that intrasaccular flow disruptor is effective and safe in wide-necked intracranial aneurysms.
9.Impact of flow diverter malapposition at the aneurysm neck on clinical outcomes and complications of intracranial aneurysms
Jie YANG ; Shuhai LONG ; Shuailong SHI ; Yukun HOU ; Ji MA ; Ye WANG ; Sheng GUAN ; Tengfei LI
Chinese Journal of Neuromedicine 2025;24(6):599-608
Objective:To investigate the impact of flow diverter (FD) malapposition at the aneurysm neck on clinical outcomes and complications of intracranial aneurysms, and identify the influencing factors for intraoperative FD malapposition.Methods:A retrospective study was performed; 153 patients with unruptured saccular aneurysms at the C4-C7 segments of the internal carotid artery accepted single FD implantation at Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from June 2022 to March 2024 were chosen. Intraoperative high-resolution C-arm CT was utilized to assess FD apposition at the aneurysm neck. (1) Based on FD apposition at the aneurysm neck as shown, these 153 patients were divided into a malapposition group ( n=23, including 16 patients with malapposition being identified as residual malapposition after intraoperative corrective measures such as microwire massage and 7 patients with malapposition being newly detected in this study) and a complete apposition group ( n=130). Perioperative and follow-up complications were recorded. Clinical outcomes were assessed using modified Rankin Scale (mRS) at the final follow-up (mRS score of 0-2 as favorable outcome), and angiographic outcomes were evaluated by DSA at the final follow-up. Differences in clinical and angiographic outcomes and complication rate were compared between the malapposition group and complete apposition group. (2) Based on FD apposition at the aneurysm neck as shown, these 153 patients were divided into an intraoperative malapposition group ( n=74, including 67 patients with malapposition being detected during surgery and 7 patients with malapposition being newly detected in this study) and an intraoperative complete apposition group ( n=79). Univariate analysis was performed to compare the clinical variables between the intraoperative malapposition group and intraoperative complete apposition group; multivariate Logistic regression was further employed to identify the independent influencing factors for FD malapposition at the aneurysm neck. Results:(1) Four patients (all from the malapposition group) developed perioperative acute in-stent thrombosis. Nine patients experienced ischemic or hemorrhagic stroke during the follow-up, including 6 from the malapposition group and 3 from the complete apposition group; the complication rate in the malapposition group (6/23, 26.1%) was significantly higher than that in the complete apposition group (3/130, 2.3%) during the follow-up ( P<0.05). At the final follow-up, 2 patients (both from the malapposition group) had poor clinical outcome, while the remaining 151 patients had favorable outcome. Proportion of patients with favorable outcome between the two groups was statistically different (91.3%[21/23] vs. 100.0%[130/130], P<0.05). Delayed occlusion was detected in 46 patients (12 from the malapposition group and 34 from the complete apposition group) at the final angiographic follow-up. FD restenosis/re-occlusion was noted in 10 patients, including 6 from the malapposition group and 4 from the complete apposition group. Significant difference in delayed occlusion rate (52.2%[12/23] vs. 26.2%[34/130]) and long-term in-stent stenosis/occlusion rate (26.1%[6/23] vs. 3.1%[4/130]) was observed between the two groups ( P<0.05). (2) Significant difference in aneurysm neck diameter, FD angulation, parent artery stenosis, parent artery diameter ratio>1.2, and presence of branching vessels at the FD implantation site was noted between the intraoperative complete apposition group and intraoperative malapposition group ( P<0.05). Multivariate Logistic regression indicated that aneurysm neck diameter ( OR=1.431, 95% CI: 1.096-1.868, P=0.008), parent artery diameter ratio>1.2 ( OR=2.199, 95% CI: 1.083-4.463, P=0.029), and FD angulation ( OR=1.019, 95% CI: 1.002-1.036, P=0.027) were independent influencing factors for FD malapposition at the aneurysm neck. Conclusion:In FD implantation for intracranial aneurysms, FD malapposition at the aneurysm neck adversely affects delayed occlusion rate and complication rate; aneurysms with wider aneurysm neck diameter, parent artery diameter ratio>1.2, and greater FD angulation are trend to have FD malapposition at the aneurysm neck.
10.Flow-diverter devices for the treatment of anterior cerebral artery aneurysms:analysis of its safety and efficacy
Wulin MA ; Mengsi AN ; Shuo LIU ; Sheng GUAN ; Xinbin GUO
Journal of Interventional Radiology 2024;33(7):711-716
Objective To investigate the safety and efficacy of flow-directed devices(flow diverter,FD)in the treatment of intracranial anterior cerebral artery aneurysms(ACAA).Methods The clinical data of 21 patients with ACAA,who were admitted to the Department of Neurointerventional Medicine of the First Affiliated Hospital of Zhengzhou University of China to receive FD treatment between February 2019 and August 2022,were retrospectively analyzed.After the treatment,O'Kelly Marotta(OKM)grading criteria was used to determine the degree of occlusion of the aneurysm,and the modified Rankin Scale(mRS)score was adopted to assess the clinical prognosis(0-2 points being defined as a good prognosis,and 3-5 points being defined as a poor prognosis).Results A total of 24 FD stents were implanted in 24 patients(24 aneurysms in total),and the technical success rate of stent implantation was 100%.During the perioperative period,complications occurred in 2 patients(8.3%),including hemorrhagic event(n=l)and ischemic event(n=l).The mRS score in all the 24 patients was ≤2 points.Follow-up imaging examination showed that OKM grade B was seen in 2 patients(8.3%),grade C in 6 patients(25%),and grade D(complete healing)in 16 patients(66.7%).Conclusion For the treatment of ACAA,the FD stent implantation is a safe and effective method.During the postoperative and the long-term follow-up period,neither serious ischemic or hemorrhagic complications nor neurological complications are observed.

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