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1.
BMC Neurol ; 20(1): 260, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600433

RESUMO

BACKGROUND: Delayed cerebral ischemia is one of the leading causes of death and disability in patients with subarachnoid hemorrhage (SAH). Transluminal balloon angioplasty (TBA) is a therapeutic option for vasospasms affecting proximal intracranial arteries. METHODS: Aim of this study was to report our experience using the Scepter C balloon catheter in the treatment of cerebral vasospasms due to SAH and evaluate the postprocedural result with the iFlow tool. We reviewed cases of patients treated at our hospital from 2014 to 2018. Patients were screened with transcranial doppler sonography (TCD) and multimodal computed tomography. In case of significant vasospasms, patients were transferred to the angiography suite and treated. We used the iFlow tool to quantify and evaluate the angiographic results by measuring and comparing peak density values on angiograms before and after the mechanical dilation. RESULTS: The use of the Scepter C balloon catheter was feasible in all cases. Vasospasms of the anterior cerebral artery were treated in ten cases. We didn't observe complications or vasospasm recurrences of the treated arteries. The temporal difference between distal vessels and the proximal reference vessel was significantly reduced from a mean of 53%, prior to dilatation, to 26% after the treatment. The difference between pre-dilatation and post-dilatation values was statistically significant for the anterior circulation at the proximal as well as at the distal vessels. CONCLUSIONS: We successfully treated endovascularly patients suffering from cerebral vasospasms refractory to medical treatment using the Scepter C balloon catheter. We didn't observe any complications. The therapeutic effect could be easily and reliably assessed with the iFlow tool.


Assuntos
Angioplastia com Balão/instrumentação , Hemorragia Subaracnóidea/complicações , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/cirurgia , Adulto , Catéteres , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
2.
BMC Med Imaging ; 19(1): 66, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412810

RESUMO

BACKGROUND: Flat detector CT - angiography (FDCTA) has become a valuable imaging tool in post- and peri-interventional imaging after neurovascular procedures. Metal artifacts produced by radiopaque implants like clips or coils still impair image quality. METHODS: FDCTA was performed in periprocedural or follow-up imaging of 21 patients, who had received neurovascular treatment. Raw data was sent to a dedicated workstation and subsequently a metal artifact reduction algorithm (MARA) was applied. Two neuroradiologists examined the images. RESULTS: Application of MARA improved image appearance and led to a significant reduction of metal artifacts. After application of MARA only 8 datasets (34% of the images) were rated as having many or extensive artifacts, before MARA 15 (65%) of the images had extensive or many artifacts. Twenty percent more cases of reperfusion were diagnosed after application of MARA, congruent to the results of digital subtraction angiography (DSA) imaging. Also 3 (13% of datasets) images, which could not be evaluated before application of MARA, could be analyzed after metal artifact reduction and reperfusion could be excluded. CONCLUSION: Application of MARA improved image evaluation, reduced the extent of metal artifacts, and more cases of reperfusion could be detected or excluded, congruent to DSA imaging.


Assuntos
Angiografia Digital/métodos , Encéfalo/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Artefatos , Encéfalo/irrigação sanguínea , Humanos , Assistência Perioperatória , Cuidados Pós-Operatórios
3.
Cerebrovasc Dis ; 45(1-2): 18-25, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29176326

RESUMO

BACKGROUND: Endovascular treatment (EVT) has been shown to significantly improve functional outcome in patients with acute large cerebral vessel occlusions. To date, no evidence-based recommendations on blood pressure management after successful EVT exist. Previous studies showed an association between high pre-EVT systolic blood pressure (SBP) and functional outcome, but do not answer the question on how to manage blood pressure after successful recanalization. The purpose of this study was to determine the role of blood pressure measurements as a predictor for early functional outcome in patients with successful EVT. METHODS: Prospectively derived data from patients with acute large vessel occlusion within the anterior circulation and EVT was analyzed in this monocentric study. Mean systolic- and maximum SBP as well as SBP-peaks have been obtained for the first 24 h after successful EVT. Predictive value of SBP for discharge modified Rankin Scale (mRS) ≤2 has been investigated using logistic regression models. RESULTS: From 168 patients with successful EVT, 74 (44%) had a favorable outcome with an mRS ≤2. Mean- (127 vs. 131 mm Hg, p = 0.035) and maximum SBP (157 vs. 169 mm Hg, p < 0.001) as well as the number of SBP-peaks (0 vs. 1.5, p = 0.004) were lower in patients with favorable outcomes. Multivariable logistic regression showed high mean- and maximum SBP to predict unfavorable outcomes. Cutoff mean SBP was 141 mm Hg and maximum SBP 159 mm Hg. CONCLUSIONS: High SBP in the first 24 h after recanalization of acute anterior cerebral vessel occlusions is associated with unfavorable functional outcome. Interventional studies are needed to determine the role of SBP management as a modifiable parameter in the early phase after successful EVT.


Assuntos
Pressão Sanguínea , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares , Acidente Vascular Cerebral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatologia , Bases de Dados Factuais , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Sístole , Fatores de Tempo , Resultado do Tratamento
4.
Stroke ; 48(11): 3152-3155, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29018132

RESUMO

BACKGROUND AND PURPOSE: Intrahospital time delays significantly affect the neurological outcome of stroke patients with large-vessel occlusion. This study was conducted to determine whether a one-stop management can reduce intrahospital times of patients with acute large-vessel occlusion. METHODS: In this observational study, we report the first 30 consecutive stroke patients imaged and treated in the same room. As part of our protocol, we transported patients with a National Institutes of Health Stroke Scale score of ≥10 directly to the angio suite, bypassing multidetector computed tomography (CT). Preinterventional imaging consisted of noncontrast flat detector CT and flat detector CT angiography, acquired with an angiography system. Patients with large-vessel occlusions remained on the angio table and were treated with mechanical thrombectomy; patients with small artery occlusions were treated with intravenous thrombolysis, whereas patients with an intracranial hemorrhage and stroke mimics were treated as per guidelines. Door-to-groin puncture times were recorded and compared with our past results. RESULTS: Thirty patients were transferred directly to our angio suite from June to December 2016. The time from symptom onset to admission was 105 minutes. Ischemic stroke was diagnosed in 22 of 30 (73%) patients, 4 of 30 (13.5%) had an intracranial hemorrhage, and 4 of 30 (13.5) were diagnosed with a Todd's paresis. Time from admission to groin puncture was 20.5 minutes. Compared with 44 patients imaged with multidetector CT in the first 6 months of 2016, door-to-groin times were significantly reduced (54.5 minutes [95% confidence interval, 47-61] versus 20.5 minutes [95% confidence interval, 17-26]). CONCLUSIONS: In this small series, a one-stop management protocol of selected stroke patients using latest generation flat detector CT led to a significant reduction of intrahospital times.


Assuntos
Angiografia Cerebral , Hemorragias Intracranianas , Admissão do Paciente , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X , Doença Aguda , Feminino , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/terapia , Masculino , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Fatores de Tempo
5.
Ann Neurol ; 80(6): 924-934, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28001316

RESUMO

OBJECTIVE: Many patients with stroke cannot receive intravenous thrombolysis because the time of symptom onset is unknown. We tested whether computed tomography (CT)-based quantification of water uptake in the ischemic tissue can identify patients with stroke onset within 4.5 hours, the time window of thrombolysis. METHODS: Perfusion CT was used to identify ischemic brain tissue, and its density was measured in native CT and related to the density of the corresponding area of the contralateral hemisphere to quantify lesion water uptake. The optimal cutoff value of water uptake distinguishing stroke onset within and beyond 4.5 hours was calculated in patients with proximal middle cerebral artery occlusion (derivation cohort) with known time of symptom onset. The so-derived cutoff value was validated in a prospective cohort from other stroke centers. RESULTS: Of 178 patients of the derivation cohort, 147 (82.6%) had CT within 4.5 hours. Percentage water uptake was significantly lower in patients with stroke onset within compared to beyond 4.5 hours. The area under the receiver operating characteristic curve for distinguishing these patient groups according to percentage water uptake was 0.999 (95% confidence interval = 0.996-1.000, p < 0.001) with an optimal cutoff value of 11.5%. Applying this cutoff to the validation cohort of 240 patients, sensitivity was 98.6%, specificity 90.5%, positive predictive value 99.1%, and negative predictive value 86.4%. INTERPRETATION: Quantification of brain water uptake identifies stroke patients with symptom onset within 4.5 hours with high accuracy and may guide the decision to use thrombolysis in patients with unknown time of stroke onset. Ann Neurol 2016;80:924-934.


Assuntos
Diagnóstico Precoce , Acidente Vascular Cerebral/diagnóstico por imagem , Água/metabolismo , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Acidente Vascular Cerebral/metabolismo , Fatores de Tempo , Tomografia Computadorizada por Raios X
6.
BMC Neurol ; 17(1): 89, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28490351

RESUMO

BACKGROUND: There are contradictory reports concerning the validity of transcranial sonography (TCD and TCCS) for examinations of the basilar artery. Here we investigated sensitivity and specificity of transcranial sonography for the detection of basilar artery stenosis and in-stent-restenosis compared to cerebral angiography. METHODS: We analyzed data of 104 examinations of the basilar artery. The association between sonographic peak systolic velocity (PSV) and degree of stenosis obtained by cerebral angiography was evaluated applying Spearman's correlation coefficient. Receiver Operating Characteristics (ROC) curves and areas under the curve (AUC) were calculated for the detection of a ≥50% stenosis defined by angiography. Optimal cut-off was derived using the Youden-index. RESULTS: A weak but statistically significant correlation between PSV and the degree of stenosis was found (n=104, rho=0.35, p<0.001). ROC analysis for a detection of ≥50% stenosis showed an AUC of 0.70, a sensitivity of 74.0% and a specificity of 65.0% at the optimal cut off of 124 cm/s. Results were consistent when analyzing examinations done in stented and unstented arteries separately (TCD VS DSA/CTA in unstented artery: AUC=0.66, sensitivity 61.0%, specificity 65.0%, TCD/TCCS VS DSA in stented artery: AUC=0.63, sensitivity 71.0%, specificity 82.0%). Comparing TCCS measurements exclusively to angiography, ROC analysis showed an AUC of 1.00 for the detection of an in-stent-restenosis ≥50% with a sensitivity and specificity of 100% when a PSV of 132 cm/s was used as a cut off value. CONCLUSION: Validity of TCD in the assessment of basilar artery stenosis or in-stent restenosis is poor. First results for TCCS are promising, but due to the small samplesize further studies with larger samples sizes are warranted.


Assuntos
Angiografia Cerebral/métodos , Constrição Patológica/diagnóstico , Ultrassonografia Doppler Transcraniana/métodos , Insuficiência Vertebrobasilar/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Stents/efeitos adversos , Adulto Jovem
7.
Stroke ; 47(9): 2331-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27486173

RESUMO

BACKGROUND AND PURPOSE: Thrombectomy, primarily with stent retrievers with or without adjunctive aspiration, provided clinical benefit across multiple prospective randomized trials. Whether this benefit is exclusive to stent retrievers is unclear. METHODS: THERAPY (The Randomized, Concurrent Controlled Trial to Assess the Penumbra System's Safety and Effectiveness in the Treatment of Acute Stroke; NCT01429350) was an international, multicenter, prospective, randomized (1:1), open label, blinded end point evaluation, concurrent controlled clinical trial of aspiration thrombectomy after intravenous alteplase (IAT) administration compared with intravenous-alteplase alone in patients with large vessel ischemic stroke because of a thrombus length of ≥8 mm. The primary efficacy end point was the percent of patients achieving independence at 90 days (modified Rankin Scale score, 0-2; intention-to-treat analysis). The primary safety end point was the rate of severe adverse events (SAEs) by 90 days (as treated analysis). Patients were randomized 1:1 across 36 centers in 2 countries (United States and Germany). RESULTS: Enrollment was halted after 108 (55 IAT and 53 intravenous) patients (of 692 planned) because of external evidence of the added benefit of endovascular therapy to intravenous-alteplase alone. Functional independence was achieved in 38% IAT and 30% intravenous intention-to-treat groups (P=0.52). Intention-to-treat ordinal modified Rankin Scale odds ratio was 1.76 (95% confidence interval, 0.86-3.59; P=0.12) in favor of IAT. Secondary efficacy analyses all demonstrated a consistent direction of effect toward benefit of IAT. No differences in symptomatic intracranial hemorrhage rates (9.3% IAT versus 9.7% intravenous, P=1.0) or 90-day mortality (IAT: 12% versus intravenous: 23.9%, P=0.18) were observed. CONCLUSIONS: THERAPY did not achieve its primary end point in this underpowered sample. Directions of effect for all prespecified outcomes were both internally and externally consistent toward benefit. It is possible that an alternate method of thrombectomy, primary aspiration, will benefit selected patients harboring large vessel occlusions. Further study on this topic is indicated. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01429350.


Assuntos
Isquemia Encefálica/terapia , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Administração Intravenosa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Resultado do Tratamento , Adulto Jovem
8.
Eur Radiol ; 26(11): 4213-4219, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26905866

RESUMO

OBJECTIVES: CTP images analyzed with the Alberta stroke program early CT scale (ASPECTS) have been shown to be optimal predictors of clinical outcome. In this study we compared two biomarkers, the cerebral blood volume (CBV)-ASPECTS and the CTA-ASPECTS as predictors of clinical outcome after thrombectomy. METHODS: Stroke patients with thrombosis of the M1 segment of the middle cerebral artery were included in our study. All patients underwent initial multimodal CT with CTP and CTA on a modern CT scanner. Treatment consisted of full dose intravenous tissue plasminogen activator, when applicable, and mechanical thrombectomy. Three neuroradiologists separately scored CTP and CTA images with the ASPECTS score. RESULTS: Sixty-five patients were included. Median baseline CBV-ASPECTS and CTA-ASPECTS for patients with favourable clinical outcome at follow-up were 8 [interquartile range (IQR) 8-9 and 7-9 respectively]. Patients with poor clinical outcome showed a median baseline CBV-ASPECTS of 6 (IQR 5-8, P < 0.0001) and a median baseline CTA-ASPECTS of 7 (IQR 7-8, P = 0.18). Using CBV-ASPECTS and CTA-ASPECTS raters predicted futile reperfusions in 96 % and 56 % of the cases, respectively. CONCLUSIONS: CBV-ASPECTS is a significant predictor of clinical outcome in patients with acute ischemic stroke treated with mechanical thrombectomy. KEY POINTS: • CBV-ASPECTS is a significant predictor of clinical outcome. • Single phase CTA-ASPECTS has low predictive value. • Using CBV-ASPECTS, raters identified futile reperfusions in 96 % of the cases.


Assuntos
Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Biomarcadores/metabolismo , Volume Sanguíneo/fisiologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/cirurgia , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Angiografia por Tomografia Computadorizada/métodos , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/cirurgia , Masculino , Imagem Multimodal/métodos , Variações Dependentes do Observador , Prognóstico , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Ativador de Plasminogênio Tecidual/metabolismo , Resultado do Tratamento
9.
Crit Care Med ; 43(9): e386-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26110491

RESUMO

OBJECTIVES: After suffering from severe acute respiratory distress syndrome, several patients show generalized brain alterations and atrophy. A distinctive morphologic pattern of cerebral injury, however, has not been found so far. DATA SOURCES: We present the history of three patients who survived severe acute respiratory distress syndrome. In these patients, MRI of the brain showed multiple microhemorrhages predominantly in the splenium of the corpus callosum. An identical pattern of microhemorrhages has previously been described in mountaineers who suffered from high-altitude cerebral edema. CONCLUSIONS: This report demonstrates that patients after treatment for acute respiratory distress syndrome and high-altitude cerebral edema show congruent cerebral injuries. Further investigation into the similarities of the causative conditions and neurologic consequences might reveal underlying pathophysiologic mechanisms and clinical implications of this observation.


Assuntos
Doença da Altitude/patologia , Edema Encefálico/patologia , Corpo Caloso/patologia , Hemorragia/patologia , Síndrome do Desconforto Respiratório/patologia , Adolescente , Adulto , Idoso , Encéfalo/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Insuficiência Respiratória
10.
Eur Radiol ; 24(2): 390-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24078013

RESUMO

OBJECTIVES: In acute stroke patients with large vessel occlusion, collateral blood flow affects tissue fate and patient outcome. The visibility of collaterals on computed tomography angiography (CTA) strongly depends on the acquisition phase, but the optimal time point for collateral imaging is unknown. METHODS: We analysed collaterals in a time-resolved fashion using four-dimensional (4D) CTA in 82 endovascularly treated stroke patients, aiming to determine which acquisition phase best depicts collaterals and predicts outcome. Early, peak and late phases as well as temporally fused maximum intensity projections (tMIP) were graded using a semiquantitative regional leptomeningeal collateral score, compared with conventional single-phase CTA and correlated with functional outcome. RESULTS: The total extent of collateral flow was best visualised on tMIP. Collateral scores were significantly lower on early and peak phase as well as on single-phase CTA. Collateral grade was associated with favourable functional outcome and the strength of this relationship increased from earlier to later phases, with collaterals on tMIP showing the strongest correlation with outcome. CONCLUSIONS: Temporally fused tMIP images provide the best depiction of collateral flow. Our findings suggest that the total extent of collateral flow, rather than the velocity of collateral filling, best predicts clinical outcome. KEY POINTS: • Collateral flow visibility on CTA strongly depends on the acquisition phase • tMIP offers the best visualisation of the extent of collaterals • Outcome prediction may be better with tMIP than with earlier phases.• Total extent of collaterals seems more important than their filling speed • If triggered too early, CTA may underestimate collateral flow.


Assuntos
Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Circulação Colateral/fisiologia , Tomografia Computadorizada Quadridimensional/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fluxo Sanguíneo Regional/fisiologia , Índice de Gravidade de Doença , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo
11.
Stroke ; 44(8): 2188-93, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23715960

RESUMO

BACKGROUND AND PURPOSE: Patient selection is crucial in the endovascular treatment of acute ischemic stroke patients. Baseline computed tomographic (CT) images, evaluated with the Alberta Stroke Program Early CT Scale (ASPECTS), are considered significant predictors of outcome. In this study, we evaluated CT images and perfusion parameters, analyzed with ASPECTS, as final outcome predictors after endovascular stroke treatment. METHODS: We analyzed a cohort of patients with acute ischemic stroke and endovascular treatment. Patients with an occlusion of the M1 segment and multimodal CT imaging were included. CT perfusion data were reconstructed using commercial software. Two experienced neuroradiologists separately reviewed and scored CT and CT perfusion images with the ASPECTS score. Parameters were compared between patients with poor and with favorable follow-up outcome. Significantly different variables were further analyzed by forward stepwise logistic regression. RESULTS: Fifty-one patients were included in our study. Baseline characteristics did not differ between patients with favorable and poor outcomes. No significant difference in recanalization status, the various times, or CT ASPECTS was demonstrated between these 2 groups. Significant differences were demonstrated for age (P=0.0049), cerebral blood volume ASPECTS (P=0.0007), and between cerebral blood volume and cerebral blood flow ASPECTS (P=0.0045). Cerebral blood volume ASPECTS>7 demonstrated the highest sensitivity and specificity for favorable outcome with 84% and 79%, respectively. CONCLUSIONS: CT perfusion parameters, evaluated with ASPECTS, are optimal predictors of outcome and are more sensitive and specific than CT ASPECTS in the prediction of favorable outcome. Use of these parameters in treatment decisions could reduce futile recanalizations.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Trombectomia/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/classificação , Isquemia Encefálica/cirurgia , Estudos de Coortes , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Acidente Vascular Cerebral/classificação , Acidente Vascular Cerebral/cirurgia , Resultado do Tratamento , Adulto Jovem
12.
Neuroradiology ; 55(7): 813-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23588613

RESUMO

INTRODUCTION: Flat-panel angiographic CT after intravenous contrast agent application (ivACT) is increasingly used as a follow-up examination after coiling, clipping, or stenting. The purpose of this study was to evaluate the feasibility of a new metal artefact reduction algorithm (MARA) in patients treated for intracranial aneurysms and stenosis. METHODS: IvACT was performed on a flat-panel detector angiography system after intravenous application of 80 ml contrast media. The uncorrected raw images were transferred to a prototype reconstruction workstation where the MARA was applied. Two experienced neuroradiologists examined the corrected and uncorrected images on a commercially available workstation. RESULTS: Artefacts around the implants were detected in all 16 uncorrected cases, while eight cases showed remaining artefacts after correction with the MARA. In the cases without correction, there were 11 cases with "extensive" artefacts and five cases with "many" artefacts. After correction, seven cases showed "few" and only one case "many" artefacts (Wilcoxon test, P < 0.001). Parent vessels were characterized as "not identifiable" in 62% of uncorrected images, while the delineation of parent vessels were classified as "excellent" in 50% of the cases after correction (Wilcoxon test, P = 0.001). CONCLUSIONS: Use of the MARA in our study significantly reduced artefacts around metallic implants on ivACT images and allowed for the delineation of surrounding structures.


Assuntos
Algoritmos , Artefatos , Angiografia Cerebral/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Intensificação de Imagem Radiográfica/métodos , Stents , Idoso , Prótese Vascular , Angiografia Cerebral/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Trombólise Mecânica/instrumentação , Metais , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
13.
Neurol Neurochir Pol ; 47(1): 32-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23487292

RESUMO

BACKGROUND AND PURPOSE: New angiographic devices with flat panel detectors allow cross-sectional imaging within the angiographic suite. In patients receiving external ventricular drainage (EVD) to manage hydrocephalus following subarachnoid haemorrhage (SAH), these may help evaluating the position of an EVD without moving the patient to a conventional computed tomography (CT) scanner. It could facilitate patients' management in a life-threatening status. This study therefore compares conventional CT with post-interventional flat panel detector angiographic CT (FDCT) referring to the determinability of an accurate EVD position. MATERIAL AND METHODS: Twenty patients with SAH received FDCT and conventional CT for primary assessment after EVD insertion. Three single-blinded raters compared both modalities and evaluated the image sufficiency for determining the EVD position, EVD tip, intracranial course and whether a contorted drainage tube could be detected. RESULTS: FDCT was sufficient to detect a correct EVD position in 82.5% of the cases vs. 100% in conventional CT. Regarding the EVD tip, FDCT delivered at least 'good' results in 82.5% vs. 95% in conventional CT data. Determining the EVD intracranial course, FDCT provided at least 'good' data in 92.5% vs. 100% in conventional CT. For detecting tube contortion, FDCT provided at least 'good' results in 70% vs. 98% in conventional CT. CONCLUSIONS: FDCT is a promising method to determine the correct position of an EVD in patients with SAH. Following a neuroradiological intervention, it facilitates the patients' management and renders additional transfers to conventional CT unnecessary in the majority of cases.


Assuntos
Angiografia Cerebral/métodos , Drenagem/métodos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Tomografia Computadorizada por Raios X/enfermagem , Ventriculostomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos de Viabilidade , Feminino , Humanos , Hidrocefalia/etiologia , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Tomografia Computadorizada por Raios X/métodos
14.
Stroke ; 43(1): 97-102, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22034000

RESUMO

BACKGROUND AND PURPOSE: Multimodal CT imaging consisting of nonenhanced CT, CT angiography (CTA), and whole-brain volume perfusion CT is increasingly used for acute stroke imaging. In these patients, presence of vessel occlusion is an important factor governing treatment decisions and possible endovascular therapy. The goal of this study was to assess the value and diagnostic accuracy of angiographic thin-slice volume perfusion CT reconstructions for the detection of intracranial large vessel occlusion in patients with stroke. METHODS: Fifty-eight patients with acute stroke received nonenhanced CT, CTA, and volume perfusion CT. All images were obtained on a 128-slice multidetector CT scanner. CT angiographic axial and coronal maximum-intensity projections of the head were reconstructed from conventional CTA and from the peak arterial scan of the volume perfusion CT data set (4-dimensional CTA). Images were assessed for the presence of intracranial vessel occlusion. The distribution of ischemic lesions was analyzed on perfusion parameter maps. RESULTS: On CTA, 30 patients (52%) had a total of 33 occluded intracranial artery segments. Twenty-eight occlusions were identified on 4-dimensional CTA, resulting in an 85% sensitivity with a positive predictive value of 97%. When combined with an analysis of the perfusion parameter maps, sensitivity of 4-dimensional CTA increased to 94% with a positive predictive value of 100%. CONCLUSIONS: In acute stroke, angiographic volume perfusion CT reconstructions may be a feasible option to detect intracranial arterial occlusion and evaluate patients for endovascular therapy. Sensitivity for detection of intracranial arterial occlusion can be increased by simultaneous assessment of perfusion parameter maps. Future studies should assess whether time-resolved 4-dimensional CTA may offer additional diagnostically relevant information compared with single-phase CTA.


Assuntos
Angiografia Cerebral/métodos , Processamento de Imagem Assistida por Computador/métodos , Trombose Intracraniana/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
15.
Stroke ; 43(11): 2974-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22961960

RESUMO

BACKGROUND AND PURPOSE: In acute stroke patients with intracranial vessel occlusion, angiographic demonstration of antegrade contrast opacification distal to the occlusion site (termed the "clot outline sign") has been associated with higher rates of vessel recanalization. We sought to determine whether antegrade flow can be demonstrated on time-resolved 4-dimensional computed tomographic angiography (4-dimensional CTA), whether it can be distinguished from retrograde collateral flow, and if it can be used to predict early recanalization. METHODS: Fifty-seven acute stroke patients with intracranial anterior circulation vessel occlusion were retrospectively identified. All patients had received a multimodal computed tomography examination including thin-section 4-dimensional CTA and subsequent digital subtraction angiography as part of an endovascular procedure. Pretreatment 4-dimensional CTA and single-phase CTA were assessed for presence of antegrade contrast opacification distal to the occlusion site. Digital subtraction angiograms were reviewed for preintervention Thrombolysis in Cerebral Infarction grade, presence of the clot outline sign, as well as postintervention Thrombolysis in Cerebral Infarction grade. RESULTS: On 4-dimensional CTA, evidence of antegrade flow was present in 11 of 57 cases (19.3%). Compared with angiography, 4-dimensional CTA predicted antegrade flow with 100% sensitivity and 97.9% specificity. Single-phase CTA offered 40% sensitivity and 87.2% specificity. Early recanalization occurred in 3 patients (6.5%) after intravenous thrombolysis (n=46); all demonstrated antegrade flow on 4-dimensional CTA. CONCLUSIONS: Using 4-dimensional CTA, it is possible to noninvasively distinguish antegrade flow across a cerebral artery occlusion from retrograde collateral flow. Presence of antegrade flow on 4-dimensional CTA is associated with an increased chance of early vessel recanalization.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Angiografia Cerebral/métodos , Transtornos Cerebrovasculares/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Transtornos Cerebrovasculares/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/patologia , Tomografia Computadorizada por Raios X
16.
Neuroradiology ; 54(1): 43-50, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21221557

RESUMO

INTRODUCTION: Using balloon-expandable stents (BES) for treatment of intracranial stenoses, high inflation pressures and rigidity of the device are regarded as major drawbacks limiting feasibility and safety of the procedure. Self-expanding stents (SES) were developed to facilitate lesion access and to allow for less aggressive dilatation. We analyzed data of the INTRASTENT multicentric registry to assess whether self-expanding stents significantly reduced peri-interventional complication rates. METHODS: Records of intracranial stent procedures were entered consecutively into the registry. Datasets were divided into two groups according to the type of stent used. For outcome measurement, we chose three categories: TIA/minor stroke [modified Rankin score (mRS) <2], disabling stroke, and patient death. Clinical outcome was compared between BES and SES. We analyzed types of adverse events occurring in each group in addition. RESULTS: Of 409 atherosclerotic lesions, 254 were treated with BES and 155 with SES. Technical success rates were 97.6% and 98.7%, respectively. Adverse event rates were 4.9%, 3.7%, and 0.8% for TIA/nondisabling stroke, disabling stroke, and death in the BES group compared with 5.3%, 6.0%, and 4.0% in the SES group. The differences were not statistically significant. We observed more perforator strokes after use of BES, but thromboembolic events occurred more often in the SES treatment group. CONCLUSION: Data of the INTRASTENT registry do not support the hypothesis that introduction of SES lowered the overall complication rate of intracranial stent procedures. There might be an advantage using self-expanding stents in vessel segments with important perforating arteries.


Assuntos
Cateterismo/efeitos adversos , Arteriosclerose Intracraniana/terapia , Stents/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Resultado do Tratamento
17.
J Vasc Surg ; 53(1): 61-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20875716

RESUMO

PURPOSE: Carotid angioplasty and stenting (CAS) is increasingly being used as a treatment alternative to endarterectomy (CEA) for patients with significant carotid stenosis. However, diffusion-weighted imaging (DWI) has indicated that CAS is associated with a significantly higher burden of microemboli. This study evaluated the potential effect on intellectual functions of new DWI lesions after CEA or CAS. METHODS: This prospective study analyzed the neuropsychologic outcomes after revascularization in 24 CAS and 31 CEA patients with severe carotid stenosis compared with a control group of 27 healthy individuals. All patients underwent clinical examinations, magnetic resonance imaging scans, and a neuropsychologic test battery that assessed six major cognitive domains performed immediately before CEA or CAS, ≤ 72 hours after, and at 3 months. RESULTS: New DWI lesions were detected among 15 of 21 (71%) of the CAS patients immediately after treatment but in only 1 of the 28 CEA patients (4%; P < .01). As a group, patients with new DWI lesions showed a decline in their performance in the cognitive domains, attention, and visuoconstructive functions within 72 hours of carotid revascularization. Individually, however, in none of the cognitive domains did the decreases reach a clinically relevant threshold of z < -1.5. Moreover, the cognitive performance was not significantly different between patients with and without new DWI lesions 3 months after treatment. The cognitive performance was similar between CEA and CAS patients at all points. CONCLUSIONS: The findings support the assumption that new brain lesions, as detected with DWI after CAS or CEA, do not affect cognitive performance in a manner that is long-lasting or clinically relevant. Despite the higher embolic load detected by DWI, CAS is not associated with a greater cognitive decline than CEA.


Assuntos
Estenose das Carótidas/terapia , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão , Atenção , Cognição , Imagem de Difusão por Ressonância Magnética , Endarterectomia das Carótidas , Feminino , Humanos , Aprendizagem , Imageamento por Ressonância Magnética , Masculino , Memória , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Stents
18.
Eur Radiol ; 21(9): 1811-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21573969

RESUMO

OBJECTIVES: Validation of the feasibility and efficacy of volume perfusion computed tomography (VPCT) in the preoperative assessment of cerebral gliomas by applying a 128-slice CT covering the entire tumour. METHODS: Forty-six patients (25 men, 21 women; mean age 52.8 years) with cerebral gliomas were evaluated with VPCT. Two readers independently evaluated VPCT data, drawing volumes of interest (VOIs) around the tumour according to maximum intensity projection volumes, which were mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability (Ktrans) perfusion datasets. As control, a second VOI was placed in the contralateral healthy cortex. Correlation among perfusion parameters, tumour grade, hemisphere and VOIs was assessed. The diagnostic power of perfusion parameters was analysed by receiver operating characteristics curve analyses. RESULTS: VPCT was feasible in the assessment of the entire tumour extent. Mean values of Ktrans, CBV, CBF in high-grade gliomas were significantly higher compared with low-grade (p < 0.01). Ktrans demonstrated the highest diagnostic (97% sensitivity), positive (100%) and negative (94%) prognostic values. CONCLUSIONS: VPCT was feasible in all subjects. All areas of different perfusion characteristics are depicted and quantified in colour-coded 3D maps. The derived parameters correlate well with tumour histopathology, differentiating low- from high-grade gliomas.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Glioma/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Adulto , Idoso , Análise de Variância , Biópsia por Agulha , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Circulação Cerebrovascular/fisiologia , Estudos de Coortes , Meios de Contraste , Estudos de Viabilidade , Feminino , Glioma/patologia , Glioma/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Perfusão/métodos , Cuidados Pré-Operatórios/métodos , Curva ROC , Sensibilidade e Especificidade
19.
Neuroradiology ; 53(5): 359-65, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20721544

RESUMO

INTRODUCTION: Carotid artery stenting (CAS) requires adequate follow-up imaging to assess complications such as in-stent stenosis or occlusion. Options include digital subtraction angiography, CT angiography, ultrasound, and MR angiography (MRA), which may offer a non-invasive option for CAS follow-up imaging. The aim of this study was to assess contrast-enhanced MRA (CE-MRA) and three-dimensional time-of-flight MRA (3D-TOF) for visualization of the in-stent lumen in different carotid stents. METHODS: In this study, we compared CE-MRA and 3D-TOF of five different carotid stents (Guidant Acculink®, Cordis Precise®, Boston Wallstent®, Abbot Vascular Xact®, Cook Zilver®) in three diameters (4, 6, and 8 mm) using a vascular flow model at 3.0 T with the help of a recently developed carotid surface coil. Stent-related artifacts were objectively assessed by calculating artificial lumen narrowing (ALN) and relative in-stent signal (RIS). RESULTS: RIS and ALN depended heavily on stent type, stent diameter, and the employed MR sequence. ALN and RIS were relatively favorable for Acculink®, Precise®, and Zilver® stents with both CE-MRA and 3D-TOF. CE-MRA provided better results for the Wallstent, while the Xact stent was difficult to visualize with both MRA protocols. CONCLUSION: Both CE-MRA and 3D-TOF are viable options for depicting the in-stent lumen in carotid stents. For specific stents, 3D-TOF provided image quality comparable to CE-MRA and may thus be suitable for in vivo assessment. Development of stent-specific pathways for follow-up imaging seems advisable to address stent-related differences in image quality.


Assuntos
Circulação Sanguínea , Artérias Carótidas/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Modelos Biológicos , Stents/classificação , Estenose das Carótidas/terapia , Meios de Contraste , Seguimentos , Humanos , Angiografia por Ressonância Magnética/classificação , Resultado do Tratamento
20.
Neurosurg Rev ; 34(3): 337-45; discussion 345, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21614428

RESUMO

There is consensus that intracranial dural arteriovenous fistulae (dAVF) with direct (non-sinus-type) or indirect (sinus-type) retrograde filling of a leptomeningeal vein should be treated due to the high risk of neurological deficits and hemorrhage. No consensus exists on treatment modality (surgery and/or embolization) and, if surgery is performed, on the best surgical strategy. This series aims to evaluate the role of surgery in the management of aggressive dAVFs. Forty-two patients underwent surgery. Opening and packing the sinus with thrombogenic material was performed in 9 of the 12 sinus-type dAVFs. In two sinus-type fistulae of the cavernous sinus and 1 of the torcular, microsurgery was used as prerequisite for subsequent embolization by providing access to the sinus. In the 30 non-sinus-type dAVFs, surgery consisted of interruption of the draining vein at the intradural entry point. In 41 patients undergoing 43 operations, elimination of the dAVF was achieved (97.6%). In one case, a minimal venous drainage persisted after surgery. The transient surgical morbidity was 11.9% (n=5) and the permanent surgical morbidity 7.1% (n=3). Our surgical strategy was to focus on the arterialized leptomeningeal vein in the non-sinus-type and on the arterialized sinus segment in the sinus-type dAVFs allowing us to obliterate all but one dAVF with a low morbidity rate. We therefore propose that microsurgery should be considered early in the treatment of both types of aggressive dAVFs. In selected cases of cavernous sinus dAVFs, the role of microsurgery is reduced to that of an adjunct to endovascular therapy.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/cirurgia , Cavidades Cranianas/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Seio Cavernoso/cirurgia , Angiografia Cerebral , Cavidades Cranianas/patologia , Embolização Terapêutica , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/terapia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Resultado do Tratamento
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