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1.
Interv Neuroradiol ; 25(6): 688-691, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31159630

RESUMO

Treatment of selective intracranial aneurysms treated with a Willis covered stent is safe and effective. We describe a previously unreported case of a large, irregular, carotid-ophthalmic aneurysm that was treated with a Willis covered stent. An immediate angiogram after the procedure showed complete occlusion of the aneurysm. However, a six-month follow-up angiogram demonstrated contrast media filling of the aneurysm neck. To the best of our knowledge, this is the first report of a recurrent aneurysm treated with a Willis covered stent because of a membrane partially isolated with the stent. This case suggests that an aneurysm that is treated with a Willis covered stent might recanalise, and the risk of aneurysm rupture persists when the membrane of the stent is isolated with the stent. Therefore, follow-up angiography is necessary, even if an immediate angiogram shows complete aneurysm occlusion. Long-term follow-up is required, and the final outcome of such a case is still unknown.

2.
J Transl Med ; 17(1): 160, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31096981

RESUMO

BACKGROUND: Flow diverter devices are increasingly used for endovascular treatment of internal carotid artery aneurysms. Treatment of ophthalmic segment aneurysms with flow diverter devices also includes coverage of the ophthalmic artery but may result in complications. It is unclear, however, whether these devices mechanically block blood flow in the ophthalmic artery. Also unclear is the relationship between deployment of a flow diverter device and post-treatment occlusion. We studied hemodynamic changes in the ophthalmic artery after deployment of a flow diverter device to determine the relationship between those changes and post-stent occlusion of the artery. METHODS: We analyzed hemodynamic modifications in the ophthalmic artery in 21 patients (19 women, 2 men; mean age 53.43 ± 7.32 years) treated by a single pipeline embolization device. Patient-specific geometries were determined from three-dimensional digital subtraction angiography and the stenting process was simulated. Computational fluid dynamics technology was used to analyze the change in ophthalmic artery hemodynamics. We compared pre-treatment and post-treatment flow velocity of the ophthalmic artery. RESULTS: Among the 21 patients with aneurysms located in the ophthalmic segment, no ophthalmic artery occlusion was found during immediate or follow-up angiography. Post-stent flow velocity in the ophthalmic artery decreased from 0.35 ± 0.19 to 0.33 ± 0.20 m/s, with the difference not being statistically significant (P = 0.106). CONCLUSION: Our results showed no significant change in ophthalmic artery blood flow after pipeline embolization device deployment. Hence, post-stent occlusion of the ophthalmic artery could not be explained by reduced blood flow. Delayed thrombosis and neointimal formation maybe the keys to ophthalmic artery occlusion and need further investigation.

3.
J Transl Med ; 16(1): 263, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30257699

RESUMO

BACKGROUND: Ruptured aneurysms, the commonest cause of nontraumatic subarachnoid hemorrhage, can be catastrophic; the mortality and morbidity of affected patients being very high. Some risk factors, such as smoking, hypertension and female sex have been identified, whereas others, such as hemodynamics, imaging, and genomics, remain unclear. Currently, no accurate model that includes all factors for predicting such rupture is available. We plan to use data from a large cohort of Chinese individuals to set up a multidimensional model for predicting risk of rupture of unruptured intracranial aneurysms (UIAs). METHODS: The China Intracranial Aneurysm Project-2 (CIAP-2) will comprise screening of a cohort of 500 patients with UIA (From CIAP-1) and focus on hemodynamic factors, high resolution magnetic resonance imaging (HRMRI) findings, genetic factors, and biomarkers. Possible risk factors for rupture of UIA, including genetic factors, biomarkers, HRMRI, and hemodynamic factors, will be analyzed. The first project of the China Intracranial Aneurysm Project (CIAP-1; chaired by the Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China) will prospectively collect a cohort of 5000 patients with UIA from 20 centers in China, and collect baseline information for each patient. Multidimensional data will be acquired in follow-up assessments. Statistically significant clinical features in the UIA cohort will also be analyzed and integrated into the model for predicting risk of UIA rupture. After the model has been set up, the resultant evidence-based prediction will provide a preliminary theoretical basis for treating aneurysms at high risk of rupture. DISCUSSION: This study will explore the risk of rupture of aneurysms and develop a scientific multidimensional model for predicting rupture of unruptured intracranial aneurysms. Clinical Trials registration A Study on a Multidimensional Prediction Model for Rupture Risk of Unruptured Intracranial Aneurysms (CIAP-2), NCT03133624. Registered: 16 April 2017. https://clinicaltrials.gov/ct2/show/NCT03133624.

4.
Med Sci Monit ; 23: 1428-1435, 2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28333907

RESUMO

BACKGROUND Flow-diverting stent (FDS) has been suggested as an effective intracranial aneurysm treatment. However, the effects of FDS on collateral branches of an aneurysm parent artery still remain unknown. Thus, the present study aimed to comprehensively evaluate the effects of placing a FDS in the intracranial collateral artery, using a miniature pig animal model. MATERIAL AND METHODS Ten healthy miniature pigs were included in the study: one pig was reserved as a control and the remaining nine pigs were placed in three experimental groups: FDS (i.e., Pipeline), LVIS, and Solitaier-AB stent groups. Pigs in the experimental groups were examined by cerebral angiography immediately after stent placement, followed by hemodynamic analyses. In addition, magnetic resonance imaging (MRI) of the brain of pigs in the experimental groups was performed to inspect the brain for obstruction and blood flow. Stents were examined for the growth of neointimas. RESULTS The results showed that neointimas, consisting of smooth muscle cells, collagenous fibers, and macrophages, were 0.67 mm thick on average and partially covered the stent wires. The thickness of neointimas in the FDS group was significantly higher than in the two conventional intracranial stent groups. There was no obvious obstruction identified in collateral arteries where the FDS was placed. CONCLUSIONS These results indicated that neointimas in collateral arteries of a miniature pig would be slightly thickened after one month of FDS placement; and FDS was shown to be safe for collateral arteries.


Assuntos
Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/terapia , Animais , Artérias , Angiografia Cerebral , Hemodinâmica , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/cirurgia , Masculino , Stents , Suínos , Porco Miniatura , Resultado do Tratamento
5.
World Neurosurg ; 99: 809.e7-809.e10, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28087432

RESUMO

BACKGROUND: Ruptured intracranial fusiform aneurysms involving small-diameter parent arteries are difficult to treat. Parent artery occlusion is a relatively simple and reliable treatment. However, occasionally, the parent arteries have to be retained. The arrival of the low-profile stent (LVIS Jr.) has made reconstructive endovascular treatment for fusiform aneurysms involving small-diameter parent arteries possible. CASE DESCRIPTION: This report describes an innovative method for stent-assisted coiling (stenting after coiling technique using only 1 microcatheter) and describes our initial experience and feasibility of this technique. However, this report carries all limitations of a technical case report of a single patient, including reproducibility, unknown potential of complications, absence of long-term follow-up, and comparative effectiveness or safety with current known techniques. CONCLUSIONS: Stenting after a coiling technique using the LVIS Jr. stent provides a possible method for reconstructive endovascular treatment of intracranial fusiform aneurysms with parent arteries <1.5 mm in diameter.


Assuntos
Aneurisma Roto/cirurgia , Cerebelo/irrigação sanguínea , Procedimentos Endovasculares , Aneurisma Intracraniano/cirurgia , Stents , Adulto , Aneurisma Roto/diagnóstico por imagem , Angiografia Cerebral , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Artéria Vertebral/diagnóstico por imagem
6.
World Neurosurg ; 97: 344-350, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27742509

RESUMO

BACKGROUND: Intracranial vertebral artery dissecting aneurysms (VADAs) tend to recur despite successful stent-assisted coil embolization (SACE). Hemodynamics is useful in evaluating aneurysmal formation, growth, and rupture. Our aim was to evaluate the hemodynamic patterns of the recurrence of VADA. METHODS: Between September 2009 and November 2013, all consecutive patients with recurrent VADAs after SACE in our institutions were enrolled. Recurrence was defined as recanalization and/or regrowth. We assessed the hemodynamic alterations in wall shear stress (WSS) and velocity after the initial SACE and subsequently after retreatment of the aneurysms that recurred. RESULTS: Five patients were included. After the initial treatment, 3 patients showed recanalization and 2 showed regrowth. In the 2 patients with regrowth, the 2 original aneurysms maintained complete occlusion; however, de novo aneurysm regrowth was confirmed near the previous site. Compared with 3 recanalized aneurysms, the completely occluded aneurysms showed high mean reductions in velocity and WSS after initial treatment (velocity, 77.6% vs. 57.7%; WSS, 74.2% vs. 52.4%); however, WSS remained high at the region near the previous lesion where the new aneurysm originated. After the second retreatment, there was no recurrence in any patient. Compared with the 3 aneurysms that recanalized, the 4 aneurysms that maintained complete occlusion showed higher reductions in velocity (62.9%) and WSS (71.1%). CONCLUSIONS: Our series indicated that hemodynamics might have an important role in recurrence of VADAs. After endovascular treatment, sufficient hemodynamic reduction in aneurysm dome, orifice, and parent vessel may be one of the key factors for preventing recurrence in VADAs.


Assuntos
Embolização Terapêutica/instrumentação , Modelos Cardiovasculares , Reoperação/métodos , Stents , Dissecação da Artéria Vertebral/fisiopatologia , Dissecação da Artéria Vertebral/cirurgia , Adulto , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Simulação por Computador , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Dissecação da Artéria Vertebral/diagnóstico
7.
J Stroke Cerebrovasc Dis ; 25(8): 1929-35, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27185537

RESUMO

BACKGROUND: Cavernous carotid aneurysms (CCAs) are characterized by pain and neuro-ophthalmologic deficits. The optimal treatment remains unclear, especially for asymptomatic CCAs. This study investigated the efficacy of endovascular treatment for CCAs in our center. METHODS: Data obtained from patients who underwent endovascular treatment for CCAs from July 2011 to July 2014 were reviewed. A retrospective analysis was conducted regarding the general condition, clinical presentation, aneurysm characteristics, therapeutic strategy, and prognosis of CCA patients. RESULTS: One hundred forty-seven patients who exhibited 155 CCAs were included, which comprised 46 asymptomatic and 101 symptomatic CCA cases. Forty-eight cases presented with headache, 5 cases presented with subarachnoid hemorrhage, 20 cases presented with diplopia, 38 cases presented with cranial nerve palsy, and 27 cases presented with ischemic stroke. The mean aneurysm sizes were 15.3 ± 12.2 and 8.1 ± 7.1 mm in the symptomatic and asymptomatic groups, respectively. Different treatments were administered: coil occlusion (n = 15), stent/balloon-assisted coil occlusion (n = 123), and parent artery occlusion (PAO) (n = 17). The PAO-treated group exhibited the highest aneurysm occlusion rate. Follow-up data were available for 131 cases, which included 86 symptomatic and 45 asymptomatic cases. There were no deaths. Among the symptomatic patients, 40.7% improved, 58.1% remained stable, and 1.2% worsened; 12 patients exhibited regrowth and 6 patients had repeated endovascular treatment. The asymptomatic patients remained stable, including 5 patients who exhibited regrowth and 2 patients who had repeated endovascular treatment. CONCLUSION: Endovascular treatment is safe and effective for CCAs and should be considered in patients with minimal complications, as well as in asymptomatic patients with stable symptoms.


Assuntos
Embolização Terapêutica/métodos , Aneurisma Cardíaco/complicações , Aneurisma Cardíaco/cirurgia , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , Adulto , Aspirina/uso terapêutico , Angiografia Cerebral , Clopidogrel , Feminino , Seguimentos , Aneurisma Cardíaco/tratamento farmacológico , Humanos , Aneurisma Intracraniano/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação de Plaquetas/uso terapêutico , Estudos Retrospectivos , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
8.
World Neurosurg ; 91: 218-27, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27102633

RESUMO

OBJECTIVE: To evaluate the outcomes of large or giant vertebrobasilar dissecting aneurysms (VBDAs) after endovascular total embolization by follow-up 3T magnetic resonance imaging (MRI). METHODS: Between November 2011 and July 2015, 4 patients had unruptured large or giant VBDAs that were treated with endovascular techniques with total embolization of VBDAs confirmed on follow-up angiography, but the patients had persistent or worsened symptoms. Preoperative and postoperative 3T high-resolution MRI was performed to evaluate arterial wall evolution. RESULTS: Follow-up angiographic results were satisfactory in all 4 patients; however, symptoms in cases 1, 2, and 4 worsened, and symptoms in case 3 did not improve. Postoperative high-resolution MRI in case 1 showed a new intramural hematoma, and postoperative high-resolution MRI of cases 2, 3, and 4 showed persistent intramural hemorrhagic signals. Follow-up MRI showed increased aneurysm size in cases 1, 2, and 4 but no size change in case 3. CONCLUSIONS: The efficacy of conventional endovascular treatment (e.g., internal trapping with coils, stent-assisted coiling, and stent placement without coils) for large or giant VBDAs is uncertain. Follow-up angiography alone does not adequately predict the outcome. High-resolution MRI is a worthwhile adjunct to follow these lesions.


Assuntos
Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/terapia , Embolização Terapêutica/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Imagem por Ressonância Magnética/métodos , Artéria Basilar/diagnóstico por imagem , Angiografia Cerebral , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Vertebral/diagnóstico por imagem
9.
Biomed Mater Eng ; 26 Suppl 1: S225-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406006

RESUMO

Flow diverter is a kind of stent-like devices with higher metal coverage rate, and it is deployed endovascularly to treat cerebral aneurysms, especially to treat giant aneurysms. However, there exist some arguments about its safety and efficacy. Hemodynamics is considered to play very important role during the initiation, growth and rupture of cerebral aneurysms. In this study, the models of a giant cerebral aneurysm involved a small branch at the aneurysmal sac before and after flow diverter implantation were constructed by virtual deployment, the blood flows in the models were simulated by computational fluid dynamics method. Analyzing the variations of the hemodynamics, the following conclusions were summarized. The flow diverter is very effective device to occlude the aneurysm, the flow rate at the small branch was rarely changed when the flow diverter deployed and the flow diverter.


Assuntos
Aneurisma Roto/fisiopatologia , Aneurisma Roto/cirurgia , Prótese Vascular , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/cirurgia , Modelos Cardiovasculares , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Simulação por Computador , Projeto Auxiliado por Computador , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Análise de Falha de Equipamento/métodos , Humanos , Desenho de Prótese , Ajuste de Prótese/métodos , Implantação de Prótese/métodos , Stents , Resultado do Tratamento
10.
Chin Med J (Engl) ; 128(14): 1916-21, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26168833

RESUMO

BACKGROUND: The endovascular strategy of the huge dissecting aneurysms involving the basilar artery (BA) is controversial and challenging. This study was to investigate the clinical and angiographic outcomes of the treatment of the huge dissecting aneurysms involving the BA by the internal trapping (IT) technique. METHODS: We retrospectively studied 15 patients with the huge dissecting aneurysms involving the BA treated by the IT technique between September 2005 and September 2014 in Department of Interventional Neuroradiology of Beijing Tiantan Hospital. Clinical and angiographic data were reviewed and evaluated. RESULTS: All patients were treated by the IT technique. That meant the dissecting artery and aneurysm segments were completed occlusion. After the procedure, the angiography demonstrated that all the dissecting artery and aneurysm segments were completed occlusion. Follow-up angiography was performed at 3-6 months or 12-18 months after the endovascular treatment (median 8 months), 14 patients had a good recovery. Re-canalization occurred in one patient whose aneurysm involved in bilateral vertebral arteries and the two third of the middle-lower BA. After the second treatment, the patient died by the ventricular tachycardia. CONCLUSIONS: The IT technique is a technically feasible and safe alternative for the treatment of BA dissecting aneurysms, but it is not necessarily the safest or most definitive treatment modality. The ideal treatment of the huge dissecting aneurysms involving the BA remains debatable and must be investigated on a case-by-case basis.


Assuntos
Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/terapia , Artéria Basilar/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Adolescente , Adulto , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
PLoS One ; 9(11): e113027, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25393341

RESUMO

BACKGROUND AND PURPOSE: The retreatment of recurrent intracranial vertebral artery dissecting aneurysms (VADAs) after stent assisted coiling (SAC) has not yet been studied. The purpose of this study was to evaluate the strategies and outcomes for retreatment of recurrent VADAs after SAC. METHODS: Between September 2009 and November 2013, six consecutive patients presenting with recurrent intracranial VADAs after SAC were enrolled in this study. They were all male with age ranging from 29 to 54 years (mean age, 46.2 years). The procedures of treatments and angiographic and clinical follow-up were reviewed retrospectively. Retreatment modalities were selected individually according to the characteristics of recurrence. The outcomes of retreatment were evaluated by angiographic and clinical follow-up. RESULTS: Six patients with recurrent intracranial VADAs after SAC were retreated, with second SAC in three patients, coil embolization, double overlapping stents placement and endovascular occlusion with aneurysm trapping in one patient, respectively. Immediate angiographic outcomes of retreatment were: complete occlusion in three patients, nearly complete occlusion in two patients, and contrast medium retention in dissecting aneurysm in one patient. All cases were technically successful. No complications related to endovascular procedures occurred. Angiographic follow-up was available in all five patients treated with second SAC or double overlapping stents, which was complete occlusion in four patients, obliteration of parent artery in one patient, showing no recurrence at 4-11 months (mean: 8.6 months). Clinical follow-up was performed in all six patients at 11-51 months after initial endovascular treatment and at 9-43 months after retreatment. The mRS of last clinical follow-up was excellent in five patients and mild disability in only one patient. CONCLUSIONS: Endovascular retreatment is feasible and effective for recurrent intracranial VADAs after SAC. Individualized strategies of retreatment should be enacted according to the characteristics and reasons for the recurrence.


Assuntos
Angiografia Cerebral , Oclusão de Enxerto Vascular , Stents , Artéria Vertebral , Adulto , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/epidemiologia , Oclusão de Enxerto Vascular/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/epidemiologia , Dissecação da Artéria Vertebral/cirurgia
12.
Asian Pac J Cancer Prev ; 14(1): 449-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23534771

RESUMO

Polymorphisms in DNA repair genes have been shown to influence DNA repair processes and to modify cancer susceptibility. Here we conducted a case-control study to assess the role of potential SNPs of DNA repair genes on the risk of glioma and meningioma. We included 297 cases and 458 cancer-free controls. Genotyping of XRCC1 Gln399Arg, XRCC1 Arg194Trp, XRCC2 Arg188His, XRCC3 Thr241Met, XRCC4 Ala247Ser, ERCC1 Asn118Asp, ERCC2 Lys751Gln and ERCC5 Asp1558His were performed in a 384-well plate format on the Sequenom MassARRAY platform. XRCC1 Arg194Trp (rs1799782) and ERCC2 Asp312Asn rs1799793 did not follow the HWE in control group, and genotype distributions of XRCC1 Gln399Arg rs25487, XRCC2 Arg188His rs3218536 and ERCC2 Asp312Asn rs1799793 were significantly different between cases and controls (P<0.05). We found XRCC1 399G/G, XRCC1 194 T/T and XRCC3 241T/T were associated with a higher risk when compared with the wild-type genotype. For ERCC5 Asp1558His, we found G/G genotype was associated with elevated susceptibility. In conclusion, our study has shown that XRCC1 Gln399Arg, XRCC1 Arg194Trp, XRCC3 Thr241Met and ERCC5 Asp1558His are associated with risk of gliomas and meningiomas. This finding could be useful in identifying the susceptibility genes for these cancers.


Assuntos
Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Glioma/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Adulto , Estudos de Casos e Controles , Endonucleases/genética , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Proteína Grupo D do Xeroderma Pigmentoso/genética
13.
J Neurosurg ; 117(2): 276-83, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22680247

RESUMO

OBJECT: Some totally occluded intracranial aneurysms may recur. The role of hemodynamic mechanisms in this process remains to be elucidated. The authors used computational fluid dynamic analysis and investigated the local hemodynamic characteristics at the aneurysm neck before and after total embolization, attempting to identify hemodynamic risk factors leading to recurrence of totally embolized aneurysms. METHODS: Between May 2008 and June 2010, the authors recruited 17 consecutive patients with totally occluded intracranial aneurysms (7 recanalized and 10 stable lesions). Using patient-specific 3D digital subtraction angiography data, the hemodynamic features before and after embolization were retrospectively characterized. RESULTS: The overall preembolization blood flow patterns were nearly the same in the recanalized and stable groups, with no significant difference in either the maximum wall shear stress (WSS) (p = 0.914) or the spatially averaged WSS (p = 0.322) at peak systole at the aneurysm neck. After occlusion, the overall flow pattern changed, and the WSS distribution at the treated aneurysm neck differed in the 2 groups. In all of the 7 recanalized cases, both the maximum WSS and spatially averaged WSS at peak systole at the treated aneurysm neck were higher than those at the aneurysm neck before embolization. In contrast, both parameters were decreased in 70%-80% of the stable cases. After embolization, both the maximum WSS (p = 0.021) and spatially averaged WSS (p = 0.041) at peak systole at the treated aneurysm neck were higher in the recanalized group than in the stable group. CONCLUSIONS: Higher WSS at the treated aneurysm neck after total embolization can be an important hemodynamic factor that contributes to aneurysm recurrence after endovascular treatment.


Assuntos
Simulação por Computador , Embolização Terapêutica , Hemodinâmica/fisiologia , Hidrodinâmica , Malformações Arteriovenosas Intracranianas/fisiopatologia , Malformações Arteriovenosas Intracranianas/terapia , Adulto , Idoso , Algoritmos , Angiografia Digital , Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia Cerebral , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imagem Tridimensional , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Recidiva , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Estudos Retrospectivos , Fatores de Risco , Sístole/fisiologia
14.
Eur Neurol ; 66(6): 359-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22134355

RESUMO

BACKGROUND AND PURPOSE: Intracranial aneurysms with daughter blebs appear to have a higher risk of rupture. Whether hemodynamic factors are involved in this phenomenon is not clear. METHODS: 54 patient-specific aneurysms harboring 69 daughter blebs were divided into ruptured and unruptured groups based on their clinical history. Realistic models were retrospectively constructed and analyzed by a computational fluid dynamic method. RESULTS: There were no differences in the aspect ratio and morphology type of the aneurysms, the size of blebs or other common risk factors between the two groups. The wall shear stress (WSS) was significantly lower while the oscillatory shear index (OSI) was higher in the daughter blebs than in the primary aneurysms. Bleb-bearing aneurysms with a rupture history displayed significantly lower WSS in the daughter bleb. Of the daughter blebs, 73.9% were localized to the impingement region of the inflow jet. CONCLUSION: These observations indicate that low WSS and high OSI in the daughter blebs might be involved in increasing the risk of rupture. The localized striking force caused by inflow jets may contribute to the development of daughter blebs. However, a precise role of hemodynamics in predicting the future rupture of daughter blebs needs further study.


Assuntos
Aneurisma Roto/patologia , Aneurisma Roto/fisiopatologia , Hemodinâmica/fisiologia , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Fatores de Risco , Resistência ao Cisalhamento
15.
Stroke ; 42(3): 745-53, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21233477

RESUMO

BACKGROUND AND PURPOSE: Hemodynamic factors are thought to play an important role in the initiation, growth, and rupture of cerebral aneurysms. However, the hemodynamic features in the residual neck of the partially embolized aneurysms and their influences on recanalization are rarely reported. In this study, we characterized the hemodynamics of partially occluded aneurysms, which were proven to undergo recanalization during follow-up using computational fluid dynamic analysis. METHODS: From May 2007 to June 2009, we identified 11 partial aneurysms during follow-up, including 5 recanalized cases and 6 stable cases with 3-dimensional digital subtraction angiography. We retrospectively characterized the hemodynamic features around the residual aneurysmal pouch using the available postprocedural digital subtraction angiography image data. The occluded part of the aneurysm was regarded as completely separated from the circulation. RESULTS: The overall blood flow patterns before embolization were almost the same in the recanalized and stable groups. After occlusion, the flow pattern changes, wall shear stress (WSS), and velocity at the remnant neck demonstrated different changes between the 2 groups. Specifically, in the recanalized group, high WSS regions were found near the neck in all 5 cases, with 4 of them being even higher than those before occlusion. Interestingly, in all cases, the high WSS area of the remnant neck coincided with the location where the aneurysm recanalization occurred. In the stable group, 5 out of 6 cases demonstrated lower WSS and velocity at the remnant neck after occlusion. CONCLUSIONS: High WSS and blood flow velocity were consistently observed near the remnant neck of partially embolized aneurysms prone to future recanalization, suggesting that hemodynamic factors may have an important role in aneurysmal recurrence after endovascular treatment. The difference in flow pattern could be caused by the incomplete occlusion of the aneurysms.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Aneurisma Intracraniano/etiologia , Aneurisma Intracraniano/fisiopatologia , Resistência ao Cisalhamento/fisiologia , Adulto , Idoso , Circulação Cerebrovascular/fisiologia , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Chin Med J (Engl) ; 122(16): 1851-6, 2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19781359

RESUMO

BACKGROUND: Endovascular therapy plays an important role in the treatment of brain arteriovenous malformations (BAVMs). Ethylene vinyl alcohol copolymer (Onyx) is a novel liquid embolic material. This study aimed to summarize our experience of using Onyx for embolization of BAVMs with the focus on embolization technique. METHODS: From September 2003 to November 2007, 115 patients (43 women and 72 men, with a mean age of 29 years) with BAVMs were endovascularly treated with Onyx in our department. The following features of all AVMs were evaluated prior to treatment: type of nidus and shunt, draining veins, and feeding arteries. A total of 196 endovascular procedures were performed. RESULTS: The course of endovascular treatment was completed in 88 patients. Additional sessions were planned in 27 patients. Of the 88 patients, total occlusion was obtained in 23 patients (26.1%), near-total (> 80% of the original volume) occlusion was obtained in 35 patients (39.8%) and partial occlusion (< 80% of the original volume) was obtained in 30 patients (34.1%) using embolization as the sole therapeutic technique. Mean volume reduction was 72% (range 30% - 100%) in 115 patients. Thirty four patients (38.6%, 34/88) underwent radiosurgical treatment. Additional embolization sessions were planned in 27 patients. Complications occurred in 19 patients (16.5%, 19/115), leading to death in one patient (mortality 0.9%) and permanent disabling in 3 patients (morbidity 2.6%). CONCLUSIONS: Onyx was shown to be feasible and safe for embolization of BAVMs. Proper use of the Onyx injection technique largely improved the endovascular treatment of BAVMs. Large AVMs can be adequately reduced in size through the use of additional treatment.


Assuntos
Malformações Arteriovenosas/terapia , Encefalopatias/terapia , Embolização Terapêutica/métodos , Polivinil/uso terapêutico , Adolescente , Adulto , Malformações Arteriovenosas/patologia , Encefalopatias/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
17.
Zhonghua Yi Xue Za Zhi ; 89(5): 310-3, 2009 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-19563706

RESUMO

OBJECTIVE: To establish a model of three-dimensional numerical simulation of intracranial longitypical aneurism and analyze the hemodynamic features thereof. METHODS: Ten patients with intracranial longitypical aneurism underwent surgical treatment. Intracranial vascular ultrasonography was conducted before operation. Intra-operatively three-dimensional angiography of the aneurysm was conducted and multifunctional physiological monitor was used to record the dynamic pressure and pressure wave form of the main branch parent artery. Matlab, Ansys, and Fluent software were used to simulate the blood flow of the longitypical aneurysms. RESULTS: The hemodynamic parameter levels were the highest at the inflow tract, followed by those at the outflow tract, and were the lowest at the top of aneurysm, for example, the blood flow velocity was (1.07+/-0.23) m/s, the dynamic pressure was (574+/-186) Pa, and the wall shear stress was (7.7+/-2.0) Pa at the inflow tract, all significantly higher than those at the top [(0.15+/-0.07) m/s, (37+/-13) Pa, and (0.40+/-0.13) Pa respectively, all P<0.05]. No eddy or just simple eddy occurred in the aneurysm. CONCLUSION: The dynamic pressure, velocity, and wall shear stress are the lowest at the top of longitypical aneurysm which may contribute to the rupture of aneurysm.


Assuntos
Simulação por Computador , Hemodinâmica , Aneurisma Intracraniano/fisiopatologia , Modelos Cardiovasculares , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral , Feminino , Hemodinâmica/fisiologia , Humanos , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil , Software
18.
Neuroradiol J ; 22(1): 102-7, 2009 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-24206959

RESUMO

Large intracranial aneurysms represent huge therapeutic challenges for neurosurgeons and endovascular therapists. Since they may involve entire vessels or be irregular in shape, the ratio of complete obliteration of these aneurysms with detachable coils is low and the incidence of recanalisation is very high. So the technique of stent-assisted coil placement was designed for the treatment of large intracranial aneurysms. We report our experience in the treatment of large or complex and wide-necked aneurysms using Neuroform stent-assisted coil placement. Thirty-six patients harboring large intracranial aneurysms were treated by Neuroform stent-assisted coil placement. Thirty-five Neuroform stents were delivered and deployed at the desired location. Of the 35 aneurysms successfully stented, all the aneurysms were occluded with stent-assisted coiling. Twenty-six were totally occluded, four achieved subtotal occlusion, and five incomplete occlusion at the end of the procedure. There were no complications related to the procedure except the migration of stents in two cases. All the patients recovered well. Though Neuroform stent-assisted coil placement may be a favorable technique for treatment of large intracranial aneurysms, further study is necessary to assess the long-term outcome.

19.
Chin Med J (Engl) ; 121(8): 725-9, 2008 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-18701027

RESUMO

BACKGROUND: Aneurysms with wide-necked or a large neck/fundus ratio, especially located on an arterial bifurcation or a small artery, are challenges for interventional neuroradiologist because of the risk of coil migration or coil protrusion into the parent vessels. Our study was designed to improve the efficacy and safety of the "remodeling technique" with the HyperForm balloon for these difficult aneurysms and was confirmed by a follow-up result. METHODS: From June 2004 to September 2006, forty-two patients (20 men, 22 women) with wide-necked or large neck/fundus ratio aneurysms were treated by using the "remodeling technique" with the HyperForm balloon. RESULTS: Forty wide-necked aneurysms were successfully treated with the HyperForm balloon remodeling technique with only two failed cases. Final results consisted of total occlusion in 34 cases (80.9%), subtotal in 4 (9.5%) and incomplete in 2 (4.8%). One aneurysmal rupture occurred, but no clinical consequence was shown. No thromboembolic events were observed during treatment. Final angiographic follow-up time ranged from 3 to 18 months. CONCLUSIONS: The "remodeling technique" with the HyperForm balloon is a very useful tool in the treatment of wide-necked or unfavorable neck/fundus ratio intracranial aneurysms-located on an arterial bifurcation or a small artery and, especially, located on the bifurcation of a large artery and a small one. In our experience, this technique provided a safe and efficient treatment for difficult aneurysms when the standard remodeling technique might have failed.


Assuntos
Angioplastia com Balão/instrumentação , Aneurisma Intracraniano/terapia , Angioplastia com Balão/métodos , Feminino , Humanos , Masculino
20.
Neurol Res ; 30(6): 598-602, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18647500

RESUMO

BACKGROUND: Giant and large intracranial aneurysms represent enormous therapeutic challenges for neurosurgeons as well as for endovascular therapists. Since they may involve entire vessels or be irregular in shape, the rate of complete obliteration with GDCs is low and the incidence of recanalization is very high. So the technique of stent-assisted coil placement is designed to treat aneurysms. OBJECTIVE: This study was to evaluate the endovascular treatment of giant and large intracranial aneurysms using neuroform stent-assisted coil placement. METHODS: Thirty-six patients harboring giant or large intracranial aneurysms were treated by using the neuroform stent-assisted coil placement. It was parallel to navigate the neuroform stent and the microcatheter. RESULTS: Thirty-five of neuroform stents were easily delivered and deployed at the desired location. Of the 35 aneurysms successfully stented, all the aneurysms were occluded with stent-assisted coiling. Twenty-nine were totally occluded, and six aneurysms were with neck remnants. There was no complication related to the procedure except for the asymptomatic migration of the stents in two cases. All the patients recovered well. CONCLUSION: The neuroform stent-assisted coil placement may be a favorable technique for treatment of giant and large intracranial aneurysms. Further study is necessary to assess the long-term outcome.


Assuntos
Angioplastia/instrumentação , Implante de Prótese Vascular/métodos , Aneurisma Intracraniano/cirurgia , Stents , Adulto , Idoso , Angioplastia/efeitos adversos , Angioplastia/métodos , Angiografia Cerebral/métodos , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/classificação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
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