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1.
J Stroke Cerebrovasc Dis ; 29(10): 105124, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32912535

RESUMO

OBJECTIVE: This study investigates the effect of aneurysm circulation on mortality and patient outcomes after aneurysmal subarachnoid hemorrhage (SAH) within the United States. METHODS: A retrospective cohort study was conducted using the Nationwide Inpatient Sample (NIS), a part of the Healthcare Cost and Utilization Project (HCUP), with ICD-10 codes for non-traumatic SAH between 2015-2016. Aneurysms were stratified as either anterior or posterior circulation. Multivariate logistic regression was used to find the impact of selected variables on the odds of mortality. RESULTS: The NIS reported 1,892 cases of non-traumatic SAH within the study period that were predominantly anterior circulation (82.6%), female (68.6%), white (57.7%), with mean age of 59.07 years, and in-hospital mortality of 21.4%. Anterior circulation aneurysms were associated with lower severity of initial illness (p = 0.014) but higher likelihood of vasospasm (p = 0.0006) than those of the posterior circulation. In a multivariate logistic regression analysis, mortality was associated with posterior circulation aneurysms (OR: 1.42; CI 95% 1.005-20.10, p = 0.047), increasing age (OR: 1.035; 95% CI 1.022-1.049; p < 0.0001), and shorter hospital stays (OR: 0.7838; 95% CI 0.758-0.811; p < 0.0001). Smoking history (OR: 0.825; 95% CI 0.573-1.187, p > 0.05) and vasospasm (OR: 1.005; 95% CI 0.648-1.558; p > 0.05) were not significantly associated with higher odds of mortality. CONCLUSIONS: Mortality following aneurysmal SAH is associated with posterior circulation aneurysms, and increasing age, but not smoking history or vasospasm. These findings may be useful for prognostication and counseling patients and families.


Assuntos
Aneurisma Roto/mortalidade , Circulação Cerebrovascular , Mortalidade Hospitalar , Aneurisma Intracraniano/mortalidade , Hemorragia Subaracnóidea/mortalidade , Adulto , Fatores Etários , Idoso , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/fisiopatologia , Bases de Dados Factuais , Feminino , Humanos , Pacientes Internados , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/fisiopatologia , Estados Unidos/epidemiologia
2.
J Stroke Cerebrovasc Dis ; 29(10): 105116, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32912568

RESUMO

BACKGROUND: A neck size >4.0 mm is a risk factor for recanalization after coil embolization. The high inflow magnitude of pretreatment wide-neck aneurysms may be correlated to recanalization. We aimed to elucidate the effect of the neck size on the inflow magnitude evaluated on four-dimensional (4D) flow magnetic resonance imaging (MRI) in pretreatment unruptured internal carotid artery (ICA) aneurysms. METHODS: Thirty-three untreated ICA aneurysms were subjected to 4D flow MRI to evaluate the inflow magnitude parameters including the maximum spatially-averaged inflow velocity (MSAIV), maximum inflow velocity, maximum inflow rate (MIR), and their ratios to each corresponding flow parameter in the parent artery. RESULTS: The neck size was linearly correlated to all inflow parameters investigated in this study. A strong correlation was observed between the neck size and the following: MSAIV (r = .755, p < .0001), MIR (r = .715, p < .0001), MSAIV ratio (r = .724, p < .0001), and MIR ratio (r = .741, p < .0001). The predicted value of MIR ratio of an aneurysm with the neck size of 4.0 mm was 23.0% and 20.6%, based on the linear regression equation of all aneurysms and on that of aneurysms with the neck size >4.0 mm, respectively. CONCLUSIONS: The neck size was linearly correlated with the inflow magnitude of unruptured ICA aneurysms. Inflow magnitude evaluation using 4D flow MRI may help to hemodynamically identify aneurysms with a high risk of recanalization after endovascular coil embolization.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Circulação Cerebrovascular , Aneurisma Intracraniano/diagnóstico por imagem , Imagem por Ressonância Magnética , Imagem de Perfusão/métodos , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Feminino , Humanos , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
3.
J Stroke Cerebrovasc Dis ; 29(9): 105039, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32807451

RESUMO

BACKGROUND: Data comparing the effect of age on outcomes of patients who underwent either endovascular coiling (EVC) or neurosurgical clipping (NSC) for ruptured intracranial aneurysms remains limited. OBJECTIVE: To better elucidate the preferred intervention for ruptured aneurysm management by presenting the results of our systematic review of the literature that evaluated the potential advantages of the two interventions between different age groups. METHODS: Systematic review of PubMed and Embase was performed (2002 - June 10, 2019) following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2013 guidelines. Median ages of EVC and NSC cohorts were 54 and 56, respectively. Ages below the median were used in our "younger" cohort; ages above the median were used in our "older" cohort. RESULTS: We reviewed 13 studies on 7,137 patients. In the younger cohort, there were 2840 (EVC: 1412, NSC: 1428) patients. In the older cohort, there were 4297 (EVC: 2552, NSC: 1745) patients. Overall, there was a significant difference in functionality between EVC (77.70%) and NSC (69.23%) (OR=1.69; 95% C.I.: 1.10-2.60, p = 0.0212). In our younger cohort, functionality was significantly different between EVC (77%) and NSC (69%) (OR=1.54; 95% C.I.: 1.29-1.84, p < 0.001). For the older cohort, there was no significant difference in functionality, complications, or efficacy. CONCLUSIONS: We have highlighted the importance of considering age prior to deciding which intervention is most appropriate for ruptured aneurysms, with higher morbidity and mortality with NSC versus EVC in the younger population.


Assuntos
Aneurisma Roto/terapia , Procedimentos Endovasculares , Aneurisma Intracraniano/terapia , Procedimentos Neurocirúrgicos , Fatores Etários , Idoso , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/mortalidade , Aneurisma Roto/fisiopatologia , Tomada de Decisão Clínica , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/mortalidade , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/mortalidade , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Resultado do Tratamento
4.
PLoS One ; 15(6): e0233981, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497124

RESUMO

We aimed to examine aneurysm hemodynamics with intra-saccular pressure measurement, and compare the effects of coiling, stenting and stent-assisted coiling in proximal segments of intracranial circulation. A cohort of 45 patients underwent elective endovascular coil embolization (with or without stent) for intracranial aneurysm at our department. Arterial pressure transducer was used for all measurements. It was attached to proximal end of the microcatheter. Measurements were taken in the parent artery before and after embolization, at the aneurysm dome before embolization, after stent implantation, and after embolization. Stent-assisted coiling was performed with 4 different stents: LVIS and LVIS Jr (Microvention, Tustin, CA, USA), Leo (Balt, Montmorency, France), Barrel VRD (Medtronic/ Covidien, Irvine, CA, USA). Presence of the stent showed significant reverse correlation with intra-aneurysmal pressure-both systolic and diastolic-after its implantation (r = -0.70 and r = -0.75, respectively), which was further supported by correlations with stent cell size-r = 0.72 and r = 0.71, respectively (P<0.05). Stent implantation resulted in significant decrease in diastolic intra-aneurysmal pressure (p = 0.046). Systolic or mean intra-aneurysmal pressure did not differ significantly. Embolization did not significantly change the intra-aneurysmal pressure in matched pairs, regardless of the use of stent (p>0.05). In conclusion, low-profile braided stents show a potential to divert blood flow, there was significant decrease in diastolic pressure after stent placement. Flow-diverting properties were related to stent porosity. Coiling does not significantly change the intra-aneurysmal pressure, regardless of packing density.


Assuntos
Pressão Sanguínea , Aneurisma Intracraniano/fisiopatologia , Stents , Idoso , Pressão Arterial , Circulação Sanguínea , Prótese Vascular , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Embolização Terapêutica , Feminino , Hemodinâmica , Humanos , Aneurisma Intracraniano/terapia , Masculino , Pessoa de Meia-Idade
5.
J Stroke Cerebrovasc Dis ; 29(8): 104869, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32417244

RESUMO

Delayed intraparenchymal hemorrhage (DIPH) is one of the complications of flow diverter (FD) treatment, however, the mechanism is unclear. We present the case of a 54-year-old woman with a partially thrombosed large internal carotid artery aneurysm. She presented intraparenchymal hemorrhage in the right parietal lobe three days after the successful FD treatment. We performed endoscopic hematoma removal, and then her consciousness disturbance was fully recovered. IMP single-photon emission computed tomography showed significant increase of cerebral blood flow in the right hemisphere. We diagnosed DIPH associated with hyperperfusion after FD treatment. It is necessary to consider that DIPH due to hyperperfusion may occur after FD treatment.


Assuntos
Artéria Carótida Interna , Hemorragia Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Hematoma/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/fisiopatologia , Endoscopia , Feminino , Hematoma/etiologia , Hematoma/fisiopatologia , Hematoma/terapia , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Pessoa de Meia-Idade , Imagem de Perfusão/métodos , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
6.
Stroke ; 51(6): 1868-1872, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32397927

RESUMO

Background and Purpose- Absence of arterial wall enhancement (AWE) of unruptured intracranial aneurysms (UIA) has shown promise at predicting which aneurysms will not rupture. We here tested the hypothesis that increased enhancement during follow-up (increased intensity, extension, or thickness or appearance of de novo enhancement), assessed using vessel wall magnetic resonance imaging, was associated with higher rates of subsequent growth. Methods- Patients with UIA were included between 2012 and 2018. Two readers independently rated AWE modification on 3T vessel wall magnetic resonance imaging, and morphological changes on time-of-flight magnetic resonance angiography during follow-up. Results- A total of 129 patients harboring 145 UIA (mean size 4.1 mm) met study criteria, of which 12 (8.3%) displayed morphological growth at 2 years. Of them, 8 demonstrated increased AWE during follow-up before or concurrently to morphological growth, and 4 had preexisting AWE that remained stable before growth. In the remaining 133 (nongrowing) UIAs, no AWE modifications were found. In multivariable analysis, increased AWE, not size, was associated with UIA growth (relative risk, 26.1 [95% CI, 7.4-91.7], P<0.001). Sensitivity, specificity, positive predictive value, and negative predictive value for UIA growth of increased AWE during follow-up were, respectively, of 67%, 100%, 96%, and 100%. Conclusions- Increased AWE during follow-up of conservatively managed UIAs predicts aneurysm growth over a 2-year period. This may impact UIA management towards closer monitoring or preventive treatment. Replication in a different setting is warranted.


Assuntos
Angiografia Cerebral , Artérias Cerebrais , Bases de Dados Factuais , Aneurisma Intracraniano , Angiografia por Ressonância Magnética , Idoso , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiopatologia , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Comput Biol Med ; 120: 103759, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32421656

RESUMO

BACKGROUND: Computational fluid dynamics(CFD) of intracranial aneurysms requires flow boundary conditions(BCs) as inputs. Patient-specific BCs are usually unavailable and substituted by literature-derived generic BCs. Therefore, we investigated inter-patient BC variations and their influence on middle cerebral artery aneurysmal hemodynamics. METHOD: We retrospectively collected CT angiography and 7-T Phase-Contrast(PC)-MRI data from eight middle-cerebral-artery bifurcation aneurysms to reconstruct the geometry and measure the arterial flowrates, respectively. The coefficient of variation(CoV) was calculated for the inlet flowrate and the pulsatility index(PI). The outflow split estimated by Murray's law was compared with PC-MRI measurements. For each aneurysm, we performed seven simulations: "baseline" using PC-MRI-derived BCs and the other six with changing BCs to explore the influence of BC variations on hemodynamics. RESULTS: From PC-MRI, the inlet flowrate was 1.94 ± 0.71 cm3/s(CoV = 36%) and PI was 0.37 ± 0.13(CoV = 34%). The outflow split estimated by Murray's law deviated by 15.3% compared to PC-MRI. Comparing to "baseline" models, ±36% variations in inlet flowrate caused -61% to +89% changes in time-averaged wall shear stress(WSS), -37% to +32% in normalized WSS(NWSS; by parent-artery), and -42% to +126% in oscillatory shear index(OSI). The ±34% variations in PI caused, -46% to +67% in OSI. Applying ±15% variations in outflow split led to inflow jet deflection and -41% to +52% changes in WSS, -41% to +47% in NWSS, and -44% to +144% in OSI. CONCLUSION: Inflow rate and outflow split have a drastic impact on hemodynamics of intracranial aneurysms. Inlet waveform has a negligible impact on WSS and NWSS but major impact on OSI. CFD-based models need to consider such sensitivity.


Assuntos
Hemodinâmica , Aneurisma Intracraniano/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Angiografia por Tomografia Computadorizada , Simulação por Computador , Meios de Contraste , Humanos , Hidrodinâmica , Imageamento Tridimensional , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/fisiopatologia , Angiografia por Ressonância Magnética , Artéria Cerebral Média/patologia , Artéria Cerebral Média/fisiopatologia , Modelos Cardiovasculares , Imagem Multimodal , Fluxo Pulsátil , Estudos Retrospectivos
8.
World Neurosurg ; 139: 558-566, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32376373

RESUMO

BACKGROUND: Anatomical variations of the course of the internal carotid artery (ICA) may complicate surgical clipping of posterior communicating artery (PCoA) aneurysms by narrowing the retrocarotid window. We evaluated the efficacy of the periclinoid surgical maneuvers for expanding the retrocarotid window and analyzed computed tomography angiography (CTA) data from patients with PCoA aneurysms to define parameters for low-coursing ICAs. METHODS: Using cadaveric specimens, standard pterional craniotomies were fashioned and extradural or intradural periclinoid surgical maneuvers-cutting of the meningo-orbital band, anterior clinoidectomy, and cutting of the distal dural ring (DDR)-were performed, and their relative advantages for expanding the retrocarotid window were assessed. Additionally, preoperative CTA data from 24 patients with PCoA aneurysms used to calculate the angles of the ICA relative to the skull base. RESULTS: Periclinoid maneuvers, especially the anterior clinoidectomy, provided additional exposure of the retrocarotid space. Cutting of the DDR allowed for partial mobilization of the ICA and widened the retrocarotid surgical window, enhancing maneuverability. The anterior clinoidectomy with cutting of the DDR allowed for enhanced exposure of the medial, middle, and posterolateral aspects of the retrocarotid space. Cutting the anterior petroclinoid fold and mobilizing cranial nerve III provided wide exposure of the lateral aspect of retrocarotid space. CONCLUSION: When clipping PCoA aneurysms in the presence of normal-coursing ICAs (approximately ≥30° ICA angle), a standard pterional craniotomy with anterior clinoidectomy and cutting of the DDR allows for substantial expansion of the retrocarotid window.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Artéria Carótida Interna/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Instrumentos Cirúrgicos , Idoso , Artéria Carótida Interna/fisiopatologia , Humanos , Aneurisma Intracraniano/fisiopatologia , Masculino
9.
J Stroke Cerebrovasc Dis ; 29(7): 104853, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32389556

RESUMO

Giant thrombosed middle cerebral artery (MCA) aneurysms are difficult to treat and sometimes require complex revascularization using allografts. We describe a technical method using revascularization with a natural Y-shaped graft that provides a normal variation for a complex MCA aneurysm. A 65-year-old man with a giant thrombosed MCA aneurysm presented with right hemiparesis and aphasia. The patient had a history of clipping surgery for the ipsilateral side of the MCA aneurysm 25 years before, and a de novo aneurysm developed over the previous 18 years. For the giant thrombosed aneurysm, trapping and revascularization were performed. A natural radial artery Y-graft was used as the graft and anastomosed to both M2 trunks. The symptoms improved after surgery, and the patient was discharged 3 weeks later. This is the first report of a double-barrel bypass using a natural Y-graft. This method attained a normal variation, and the flow of the Y-graft was physiological. For the radical cure of giant thrombosed MCA aneurysms, multiple revascularizations might be required. With this natural Y-graft, complex transpositions could be avoided.


Assuntos
Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Revascularização Cerebral/instrumentação , Aneurisma Intracraniano/cirurgia , Trombose Intracraniana/cirurgia , Artéria Cerebral Média/cirurgia , Artéria Radial/transplante , Idoso , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/fisiopatologia , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiopatologia , Resultado do Tratamento
10.
Stroke Vasc Neurol ; 5(1): 14-21, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411403

RESUMO

Endovascular coil embolisation continues to evolve and remains a valid modality in managing ruptured and unruptured cerebral aneurysms. Technological advances in coil properties, adjunctive devices and interventional techniques continue to improve long-term aneurysm occlusion rates. This review elaborates on the latest advances in next-generation endovascular coils and adjunctive coiling techniques for treating cerebral aneurysms.


Assuntos
Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/terapia , Circulação Cerebrovascular , Embolização Terapêutica/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Desenho de Equipamento , Hemodinâmica , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Resultado do Tratamento
12.
Stroke Vasc Neurol ; 5(1): 22-28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411404

RESUMO

The pathophysiology of giant cerebral aneurysms renders them difficult to treat. Advances in technology have attempted to address any shortcomings associated with open surgery or endovascular therapies. Since the introduction of the flow diversion technique, the endovascular approach with flow diversion has become the first-line modality chosen to treat giant aneurysms. A subset of these giant aneurysms may persistent despite any treatment modality. Perhaps the best option for these recurrent and/or persistent giant aneurysms is to employ a multimodal approach-both surgical and endovascular-rather than any single technique to provide a curative result with favourable patient outcomes. This paper provides a review of the histopathology and treatment options for giant cerebral aneurysms. Additionally, an illustrative case is presented to highlight the unique challenges of a curative solution for giant cerebral aneurysms that persist despite initial treatment.


Assuntos
Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/terapia , Procedimentos Neurocirúrgicos , Idoso , Circulação Cerebrovascular , Terapia Combinada , Embolização Terapêutica/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Desenho de Equipamento , Hemodinâmica , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Procedimentos Neurocirúrgicos/efeitos adversos , Resultado do Tratamento
13.
J Stroke Cerebrovasc Dis ; 29(6): 104807, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32295733

RESUMO

OBJECTIVES: Balloon test occlusion (BTO) is performed to evaluate ischemic tolerance for large and giant cerebral aneurysms and head and neck tumors that may require parent artery occlusion. However, ischemic tolerance for the temporary test occlusion does not always guarantee a tolerance for permanent occlusion. In this study, we evaluated the utility of computed tomography (CT) perfusion during BTO to quantify ischemic tolerance for detecting delayed ischemic stroke. MATERIALS AND METHODS: Forty-one patients who underwent BTO for the internal carotid artery were included. The correlations between the parameters of CT perfusion and collateral angiographic appearance or stump pressure during BTO were evaluated. The cerebral blood flow (CBF), cerebral blood volume, mean transit time (MTT), and time to peak (TTP) were obtained through CT perfusion, and the asymmetry ratios were determined. Collateral angiographic appearances were categorized into 5 grades (0-4). RESULTS: The collateral angiographic appearance showed moderate correlations with CBF, MTT, and TTP that was significant. Of these, the absolute value of the correlation coefficient was the highest for MTT. MTT also showed a moderate correlation with stump pressure. CBF and MTT were significantly different between the poor collateral group (grades 2 and 3) and the good collateral group (grade 4). Based on the MTT, the good collateral group was identified with high sensitivity (75.0%) and specificity (81.2%). CONCLUSIONS: In BTO, the MTT obtained through CT perfusion showed a correlation with collateral angiographic appearance and stump pressure. Thus, the MTT might be useful to quantify ischemic tolerance for detecting delayed ischemic stroke.


Assuntos
Oclusão com Balão , Isquemia Encefálica/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Angiografia Cerebral , Circulação Cerebrovascular , Circulação Colateral , Angiografia por Tomografia Computadorizada , Aneurisma Intracraniano/diagnóstico por imagem , Imagem de Perfusão/métodos , Adolescente , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Isquemia Encefálica/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Criança , Feminino , Humanos , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto Jovem
14.
Int J Comput Assist Radiol Surg ; 15(4): 629-639, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32130645

RESUMO

PURPOSE: Cerebral aneurysms are one of the prevalent cerebrovascular disorders in adults worldwide and caused by a weakness in the brain artery. The most impressive treatment for a brain aneurysm is interventional radiology treatment, which is extremely dependent on the skill level of the radiologist. Hence, accurate detection and effective therapy for cerebral aneurysms still remain important clinical challenges. In this work, we have introduced a pipeline for cerebral blood flow simulation and real-time visualization incorporating all aspects from medical image acquisition to real-time visualization and steering. METHODS: We have developed and employed an improved version of HemeLB as the main computational core of the pipeline. HemeLB is a massive parallel lattice-Boltzmann fluid solver optimized for sparse and complex geometries. The visualization component of this pipeline is based on the ray marching method implemented on CUDA capable GPU cores. RESULTS: The proposed visualization engine is evaluated comprehensively and the reported results demonstrate that it achieves significantly higher scalability and sites updates per second, indicating higher update rate of geometry sites' values, in comparison with the original HemeLB. This proposed engine is more than two times faster and capable of 3D visualization of the results by processing more than 30 frames per second. CONCLUSION: A reliable modeling and visualizing environment for measuring and displaying blood flow patterns in vivo, which can provide insight into the hemodynamic characteristics of cerebral aneurysms, is presented in this work. This pipeline increases the speed of visualization and maximizes the performance of the processing units to do the tasks by breaking them into smaller tasks and working with GPU to render the images. Hence, the proposed pipeline can be applied as part of clinical routines to provide the clinicians with the real-time cerebral blood flow-related information.


Assuntos
Circulação Cerebrovascular/fisiologia , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Simulação por Computador , Hemodinâmica/fisiologia , Humanos , Aneurisma Intracraniano/fisiopatologia , Modelos Neurológicos
15.
J Stroke Cerebrovasc Dis ; 29(6): 104624, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32222417

RESUMO

BACKGROUND AND OBJECTIVE: There are technical challenges to complete occlusion of small (<5 mm) ruptured intracranial aneurysms (SRAs) using endovascular treatment (EVT). This study analyzed factors influencing immediate angiographic results in SRAs after EVT. MATERIAL AND METHODS: Intraoperative angiograms and medical records of 290 patients, who underwent EVT for SRAs at 2 stroke centers in China between January 2009 and October 2016, were retrospectively reviewed and evaluated. RESULTS: Immediate complete occlusion was achieved in 213 (73.4%) aneurysms. Aneurysms with a smaller aspect ratio, those less than 3 mm in size, irregular shape, small basal outpouching, multiple aneurysms, poorer Hunt and Hess grade, and location of communication arteries demonstrated higher rates of incomplete occlusion, although the differences were not statistically significant. Multivariate logistic regression analysis revealed that SRAs with parent artery stenosis greater than or equal to 50% and lobulation demonstrated a higher incidence of incomplete occlusion. Intra-procedural rupture occurred in 13 (6.1%) patients in the complete occlusion group, and 3 (3.9%) in the incomplete occlusion group (P = .467). Thromboembolic complications occurred in 3 (1.0%) patients, and 4 (1.9%) underwent decompressive craniotomy after EVT, all of whom were in the complete occlusion group. Nine (4.2%) patients in the complete occlusion group and 2 (2.6%) in the incomplete occlusion group (P = .733) experienced intraprocedural vasospasm, with corresponding morbidity and mortality rates of 15.0% and 2.1%, respectively. CONCLUSIONS: Proximal parent artery stenosis greater than or equal to 50% and lobulation were independent predictors of incomplete occlusion in patients with SRAs. Higher rates of intraprocedural rupture, thromboembolic complications, intraprocedural vasospasm, and mortality were found in the complete occlusion group; however, these differences were not statistically significant. Complete occlusion of SRAs may be achieved without additional mortality and perioperative complications.


Assuntos
Aneurisma Roto/terapia , Angiografia Cerebral , Embolização Terapêutica/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Aneurisma Intracraniano/terapia , Tromboembolia/diagnóstico por imagem , Vasoespasmo Intracraniano/diagnóstico por imagem , Adolescente , Adulto , Idoso , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/mortalidade , Aneurisma Roto/fisiopatologia , Pequim , Circulação Cerebrovascular , Embolização Terapêutica/instrumentação , Embolização Terapêutica/mortalidade , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/mortalidade , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Tromboembolia/etiologia , Tromboembolia/mortalidade , Tromboembolia/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/mortalidade , Vasoespasmo Intracraniano/fisiopatologia , Adulto Jovem
16.
Stroke ; 51(5): 1624-1628, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32192404

RESUMO

Background and Purpose- Determinants for molecular and structural instability, that is, impending growth or rupture, of intracranial aneurysms (IAs) remain uncertain. To elucidate this, we endeavored to estimate the actual turnover rates of the main molecular constituent in human IA (collagen) on the basis of radiocarbon (14C) birth dating in relation to IA hemodynamics. Methods- Collagen turnover rates in excised human IA samples were calculated using mathematical modeling of 14C birth dating data of collagen in relation to risk factors and histological markers for collagen maturity/turnover in selected IA. Hemodynamics were simulated using image-based computational fluid dynamics. Correlation, logistic regression, and receiver operating characteristic analyses were performed. Results- Collagen turnover rates were estimated in 46 IA (43 patients); computational fluid dynamics could be performed in 20 IA (20 patients). The mean collagen turnover rate (γ) constituted 126% (±1% error) per year. For patients with arterial hypertension, γ was greater than 2600% annually, whereas γ was distinctly lower with 32% (±1% error) per year for patients without risk factors, such as smoking and hypertension. There was a distinct association between histological presence of rather immature collagen in human IA and the presence of modifiable risk factors. Spatial-temporal averaged wall shear stress predicted rapid collagen turnover (odds ratio, 1.6 [95% CI, 1.0-2.7]). Receiver operating characteristic analysis demonstrated a good test accuracy (area under the curve, 0.798 [95% CI, 0.598-0.998]) for average wall shear stress with a threshold ≥4.9 Pa for rapid collagen turnover. Conclusions- Our data indicate that turnover rates and stability of collagen in human IA are strongly associated with the presence of modifiable risk factors and aneurysmal hemodynamics. These findings underline the importance of strict risk factor modification in patients with unruptured IA. Future should include more detailed risk factor data to establish a more causal understanding of hemodynamics and the rupture risk of individual IA.


Assuntos
Aneurisma Roto/epidemiologia , Colágeno Tipo I/metabolismo , Hemodinâmica/fisiologia , Aneurisma Intracraniano/metabolismo , Adulto , Idoso , Colágeno/metabolismo , Feminino , Humanos , Hipertensão/epidemiologia , Aneurisma Intracraniano/epidemiologia , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Curva ROC , Datação Radiométrica , Medição de Risco , Fatores de Risco , Fumar/epidemiologia , Remodelação Vascular
17.
Sci Rep ; 10(1): 2016, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029748

RESUMO

This study analyzed morphometric and hemodynamic parameters of aneurysmal and non-aneurysmal middle cerebral artery (MCA) bifurcations and their relationship with optimal values derived from the principle of minimum work (PMW). The study included 96 patients with MCA aneurysm and 94 controls. Aneurysm patients presented with significantly higher values of the radius and cross-sectional area of the MCA trunk, angle between the post-bifurcation branches (α angle) and volume flow rate (VFR) and had significantly lower values of junction exponent and pulsatility index than the controls. The Φ1 and Φ2 angles (angles between the MCA trunk axis and the larger and smaller branch, respectively) and α angle in all groups were significantly larger than the optimal PMW-derived angles. The most important independent predictors of MCA aneurysm were junction exponent (odds ratio, OR = 0.42), α angle (OR = 1.07) and VFR (OR = 2.36). Development of cerebral aneurysms might be an independent effect of abnormalities in hemodynamic and morphometric factors. The risk of aneurysm increased proportionally to the deviation of morphometric parameters of the bifurcation from their optimal PMW-derived values. The role of bifurcation angle in aneurysm development needs to be explained in future research as the values of this parameter in both aneurysm patients and non-aneurysmal controls in were scattered considerably around the PMW-derived optimum.


Assuntos
Circulação Cerebrovascular/fisiologia , Aneurisma Intracraniano/epidemiologia , Artéria Cerebral Média/anatomia & histologia , Adulto , Idoso , Anatomia Transversal , Estudos de Casos e Controles , Angiografia Cerebral , Feminino , Humanos , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Fatores de Risco
18.
J Stroke Cerebrovasc Dis ; 29(4): 104647, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32008923

RESUMO

BACKGROUND: Flow diverters have revolutionized the treatment of large aneurysms. However, prolapse of the device into the aneurysm is a known complication that may have fatal consequences. CASE: We present a case of a 21-year-old male with a giant aneurysm located in the cavernous segment of the right internal carotid artery. After Pipeline Embolization Device (PED) deployment, while retrieving the PED wire, the proximal end of the stent shortened, resulting in prolapse of the device into the aneurysm. We utilized the Pull on Pipe (POP) maneuver, characterized by the deployment of a second PED inside the lumen of the prolapsed device and gentle traction to restore the initial flow diverter into its proper position. The maneuver also allows for the immediate deployment of the second PED to improve proximal purchase and overall construct stability. CONCLUSION: The POP maneuver is a novel strategy for salvaging herniated flow diverters and establishing a more stable PED construct.


Assuntos
Artéria Carótida Interna , Circulação Cerebrovascular , Remoção de Dispositivo , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Migração de Corpo Estranho/terapia , Aneurisma Intracraniano/terapia , Stents , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Resultado do Tratamento , Adulto Jovem
19.
AJNR Am J Neuroradiol ; 41(3): 488-494, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32054620

RESUMO

BACKGROUND AND PURPOSE: Flow diverter-induced hemodynamic change plays an important role in the mechanism of intracranial aneurysm occlusion. Our aim was to explore the relationship between aneurysm features and flow-diverter treatment of unruptured sidewall intracranial aneurysms. MATERIALS AND METHODS: MR imaging, 4D phase-contrast, was prospectively performed before flow diverter implantation in each patient with unruptured intracranial aneurysm. Two postprocedure follow-ups were scheduled at 6 and 12 months. Responses were grouped according to whether the aneurysms were occluded or remnant. Preprocedural aneurysm geometries and ostium hemodynamics in 38 patients were compared between the 2 groups at 6 and 12 months. Receiver operating characteristic curve analyses were performed for significant geometric and hemodynamic continuous parameters. RESULTS: After the 6-month assessment, 21 of 41 intracranial aneurysms were occluded, and 9 additional aneurysms were occluded at 12 months. Geometrically, the ostium maximum diameter was significantly larger in the remnant group at 6 and 12 months (both P < .001). Hemodynamically, the proximal inflow zone was more frequently observed in the remnant group at 6 months. Several preprocedural ostium hemodynamic parameters were significantly higher in the remnant group. As a prediction for occlusion, the areas under the curve of the ostium maximum diameter (for 6 and 12 months), systolic inflow rate ratio (for 6 months), and systolic inflow area (for 12 months) reached 0.843, 0.883, 0.855, and 0.860, respectively. CONCLUSIONS: Intracranial aneurysms with a large ostium and strong ostium inflow may need a longer time for occlusion. Preprocedural 4D flow MR imaging can well illustrate ostium hemodynamics and characterize aneurysm treatment responses.


Assuntos
Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Feminino , Hemodinâmica/fisiologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
20.
PLoS One ; 15(1): e0227770, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945111

RESUMO

Blood flow in an artery is a fluid-structure interaction problem. It is widely accepted that aneurysm formation, enlargement and failure are associated with wall shear stress (WSS) which is exerted by flowing blood on the aneurysmal wall. To date, the combined effect of aneurysm size and wall elasticity on intra-aneurysm (IA) flow characteristics, particularly in the case of side-wall aneurysms, is poorly understood. Here we propose a model of three-dimensional viscous flow in a compliant artery containing an aneurysm by employing the immersed boundary-lattice Boltzmann-finite element method. This model allows to adequately account for the elastic deformation of both the blood vessel and aneurysm walls. Using this model, we perform a detailed investigation of the flow through aneurysm under different conditions with a focus on the parameters which may influence the wall shear stress. Most importantly, it is shown in this work that the use of flow velocity as a proxy for wall shear stress is well justified only in those sections of the vessel which are close to the ideal cylindrical geometry. Within the aneurysm domain, however, the correlation between wall shear stress and flow velocity is largely lost due to the complexity of the geometry and the resulting flow pattern. Moreover, the correlations weaken further with the phase shift between flow velocity and transmural pressure. These findings have important implications for medical applications since wall shear stress is believed to play a crucial role in aneurysm rupture.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Artérias Cerebrais/fisiopatologia , Aneurisma Intracraniano/etiologia , Modelos Cardiovasculares , Simulação por Computador , Elasticidade , Análise de Elementos Finitos , Humanos , Aneurisma Intracraniano/fisiopatologia , Fluxo Pulsátil , Estresse Mecânico
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