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1.
Neuroradiology ; 62(8): 1043-1050, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170371

RESUMO

PURPOSE: Using the Woven EndoBridge (WEB) for aneurysm treatment has emerged as endovascular approach aiming for flow disruption in aneurysm sac. Since quantifiable data confirming the hemodynamic effect are lacking, we investigated in vivo aneurysmal flow alterations using time-density curve (TDC) analysis. Additionally, we evaluated whether flow parameters could be identified as independent factor to predict aneurysm occlusion. METHODS: Forty cerebral aneurysm patients treated with WEB were enrolled. Pre- and postinterventional digital subtraction angiography series were postprocessed and TDCs generated. TDCs were quantified calculating the parameters aneurysmal inflow velocity, outflow velocity, mean flow velocity, and relative time-to-peak (rTTP) of aneurysm filling. Pre- and postinterventional values were compared and related to occlusion rate. RESULTS: WEB implanting induced highly significant rTTP prolongation by 52% (p = 0.001) and highly significant decrease of aneurysmal inflow, outflow, and mean flow velocity (p < 0.001). While outflow velocity was reduced by 49%, inflow velocity was reduced by 33% only. No statistically significant difference between the occluded and the non-occluded group was observed. No flow parameter reached significance level concerning predicting aneurysm occlusion. CONCLUSION: Flow quantification confirms a significant flow-disrupting effect of WEB reducing more the outflow than the inflow velocity. In our small cohort, no flow parameter reached statistical significance to show predictive value regarding complete aneurysm occlusion. The hemodynamic effect of WEB is on comparable level to flow-diverting stents meaning that aneurysm closure can be delayed. In case of only slight inflow changes and high aneurysmal hemodynamic stress, some aneurysms might not be adequately protected in the short term.


Assuntos
Prótese Vascular , Procedimentos Endovasculares/instrumentação , Hemodinâmica/fisiologia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Adulto , Idoso , Angiografia Digital , Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Cerebrovasc Dis ; 46(1-2): 72-81, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30138918

RESUMO

BACKGROUND: Troponin I is a widely used and reliable marker of myocardial damage and its levels are routinely measured in acute stroke care. So far, the influence of troponin I elevations during hospital stay on functional outcome in patients with atraumatic intracerebral hemorrhage (ICH) is unknown. METHODS: Observational single-center study including conservatively treated ICH patients over a 9-year period. Patients were categorized according to peak troponin I level during hospital stay (≤0.040, 0.041-0.500, > 0.500 ng/mL) and compared regarding baseline and hematoma characteristics. Multivariable analyses were performed to investigate independent associations of troponin levels during hospital stay with functional outcome - assessed using the modified Rankin Scale (mRS; favorable 0-3/unfavorable 4-6) - and mortality after 3 and 12 months. To account for possible confounding propensity score (PS)-matching (1: 1; caliper 0.1) was performed accounting for imbalances in baseline characteristics to investigate the impact of troponin I values on outcome. RESULTS: Troponin elevations (> 0.040 ng/mL) during hospital stay were observed in 308 out of 745 (41.3%) patients and associated with poorer status on admission (Glasgow Coma Scale/National Institute of Health Stroke Scale). Multivariable analysis revealed troponin I levels during hospital stay to be independently associated with unfavorable outcome after 12 months (risk ratio [95% CI]: 1.030 [1.009-1.051] per increment of 1.0 ng/mL; p = 0.005), but not with mortality. After PS-matching, patients with troponin I elevation (≥0.040 ng/mL) versus those without had a significant higher rate of -unfavorable outcome after 3 and 12 months (mRS 4-6 at 3 months: < 0.04 ng/mL: 159/265 [60.0%] versus ≥0.04 ng/mL: 199/266 [74.8%]; p < 0.001; at 12 months: < 0.04 ng/mL: 141/248 [56.9%] versus ≥0.04 ng/mL: 179/251 [71.3%]; p = 0.001). CONCLUSIONS: Troponin I elevations during hospital stay occur frequently in ICH patients and are independently associated with functional outcome after 3 and 12 months but not with mortality.


Assuntos
Hemorragia Cerebral/sangue , Troponina I/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/terapia , Tratamento Conservador , Bases de Dados Factuais , Avaliação da Deficiência , Feminino , Nível de Saúde , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
3.
Cerebrovasc Dis ; 43(1-2): 9-16, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27750252

RESUMO

BACKGROUND: Using flat-detector CT (FD-CT) for stroke imaging has the advantage that both diagnostic imaging and endovascular therapy can be performed directly within the Angio Suite without any patient transfer and time delay. Thus, stroke management could be speeded up significantly, and patient outcome might be improved. But as precondition for using FD-CT as primary imaging modality, a reliable exclusion of intracranial hemorrhage (ICH) has to be possible. This study aimed to investigate whether optimized native FD-CT, using a newly implemented reconstruction algorithm, may reliably detect ICH in stroke patients. Additionally, the potential to identify ischemic changes was evaluated. METHODS: Cranial FD-CT scans were obtained in 102 patients presenting with acute ischemic stroke (n = 32), ICH (n = 45) or transient ischemic attack (n = 25). All scans were reconstructed with a newly implemented half-scan cone-beam algorithm. Two experienced neuroradiologists, unaware of clinical findings, evaluated independently the FD-CTs screening for hemorrhage or ischemic signs. The findings were correlated to CT, and rater and inter-rater agreement was assessed. RESULTS: FD-CT demonstrated high sensitivity (95-100%) and specificity (100%) in detecting intracerebral and intraventricular hemorrhage (IVH). Overall, interobserver agreement (κ = 0.92) was almost perfect and rater agreement to CT highly significant (r = 0.81). One infratentorial ICH and 10 or 11 of 22 subarachnoid hemorrhages (SAHs) were missed of whom 7 were perimesencephalic. The sensitivity for detecting acute ischemic signs was poor in blinded readings (0 or 25%, respectively). CONCLUSIONS: Optimized FD-CT, using a newly implemented reconstruction algorithm, turned out as a reliable tool for detecting supratentorial ICH and IVH. However, detection of infratentorial ICH and perimesencephalic SAH is limited. The potential of FD-CT in detecting ischemic changes is poor in blinded readings. Thus, plain FD-CT seems insufficient as a standalone modality in acute stroke, but within a multimodal imaging approach primarily using the FD technology, native FD-CT seems capable to exclude reliably supratentorial hemorrhage. Currently, FD-CT imaging seems not yet ready for wide adoption, replacing regular CT, and should be reserved for selected patients. Furthermore, prospective evaluations are necessary to validate this approach in the clinical setting.


Assuntos
Isquemia Encefálica/diagnóstico , Hemorragia Cerebral/diagnóstico por imagem , Ataque Isquêmico Transitório/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Isquemia Encefálica/terapia , Hemorragia Cerebral/terapia , Hemorragia Cerebral Intraventricular/diagnóstico por imagem , Hemorragia Cerebral Intraventricular/terapia , Desenho de Equipamento , Feminino , Humanos , Ataque Isquêmico Transitório/terapia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/terapia
4.
Acta Radiol ; 57(2): 233-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25711233

RESUMO

BACKGROUND: C-arm flat panel computed tomography angiography (CA-CTA) is a relatively new imaging modality. Consequently, knowledge about postprocessing parameters and their influence on image quality is still limited, especially for the visualization of implanted microstents. PURPOSE: To optimize reconstruction parameters by evaluating the influence of these different parameters for CA-CTA visualization of microstents in an animal model. MATERIAL AND METHODS: Eleven microstents were implanted within the left common carotid artery of 11 New Zealand white rabbits. Both CA-CTA, using intra-venous delivery of contrast material, and conventional digital subtraction angiography (DSA) was performed. CA-CTA datasets were reconstructed using three different image characteristics (normal, sharp, smooth). Two experienced neuroradiologists evaluated the image quality and performed measurements of inner and outer stent diameters as well as measurements of the lumen area. RESULTS: Stent deployment was performed successfully in all animals. Inter-observer correlation coefficient for all measurements was high (r = 0.87-0.92). Lumen area and inner stent diameter were significantly smaller in image characteristic "smooth" (P < 0.01) than in "sharp" and "normal". Outer stent diameter was larger in "smooth" than in "sharp" and "normal" (P < 0.01). Stent strut size was significantly wider using image characteristic "smooth". "Sharp" and "normal" compared best to DSA, with "sharp" providing the closest match to DSA measurements, with the trade-off of significantly more noise than in the "normal" reconstructions. CONCLUSION: The use of different image characteristics in the postprocessing of CA-CTA datasets has an influence on the visualization of implanted stents. Image characteristic "sharp" and "normal" compared best to DSA.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Angiografia Digital/métodos , Animais , Meios de Contraste , Processamento de Imagem Assistida por Computador/métodos , Modelos Animais , Variações Dependentes do Observador , Coelhos , Tomógrafos Computadorizados
5.
Neurocrit Care ; 25(1): 40-6, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26690939

RESUMO

BACKGROUND: Our study aimed to evaluate whether the effect of an intra-arterial vasospasm therapy can be assessed quantitatively by in vivo blood flow analysis using the postprocessing algorithm parametric color coding (PCC). METHODS: We evaluated 17 patients presenting with acute clinical deterioration due to vasospasm following subarachnoidal hemorrhage treated with intra-arterial nimodipine application. Pre- and post-interventional DSA series were post-processed by PCC. The relative time to maximum opacification (rTmax) was calculated in 14 arterially and venously located points of interest. From that data, the pre- and post-interventional cerebral circulation time (CirT) was calculated. Additionally, the arterial vessel diameters were measured. Pre- and post-interventional values were compared and tested for significance, respectively. RESULTS: Flow analysis revealed in all arterial vessel segments a non-statistically significant prolongation of rTmax after treatment. The mean CirT was 5.62 s (±1.19 s) pre-interventionally and 5.16 s (±0.81 s) post-interventionally, and the difference turned out as statistically significant (p = 0.039). A significantly increased diameter was measurable in all arterial segments post-interventionally. CONCLUSION: PCC is a fast applicable imaging technique that allows via real-time and in vivo blood flow analysis a quantitative assessment of the effect of intra-arterial vasospasm therapy. Our results seem to validate in vivo that an intra-arterial nimodipine application induces not only vasodilatation of the larger vessels, but also improves the microcirculatory flow, leading to a shortened cerebral CirT that reaches normal range post-interventionally. Procedural monitoring via PCC offers the option to compare quantitatively different therapy regimes, which allows optimization of existing approaches and implementation of individualized treatment strategies.


Assuntos
Angiografia Digital/métodos , Circulação Cerebrovascular/efeitos dos fármacos , Monitorização Neurofisiológica/métodos , Nimodipina/farmacologia , Hemorragia Subaracnóidea/complicações , Vasodilatadores/farmacologia , Vasoespasmo Intracraniano/diagnóstico por imagem , Vasoespasmo Intracraniano/tratamento farmacológico , Adulto , Feminino , Humanos , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Nimodipina/administração & dosagem , Vasodilatadores/administração & dosagem , Vasoespasmo Intracraniano/etiologia
6.
Eur Radiol ; 25(2): 428-35, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25323602

RESUMO

OBJECTIVES: After deployment of flow-diverting stents (FDS), complete aneurysm occlusion is not predictable. This study investigated whether parametric colour coding (PCC) could allow in vivo visualization of flow alterations induced by FDS and identify favourable or adverse flow modulations. METHODS: Thirty-six patients treated by FDS were analyzed. Preinterventional and postinterventional DSA-series were postprocessed by PCC and time-density curves (TDCs) were calculated. The parameters aneurysmal inflow, outflow, and relative time-to-peak (rTTP) were calculated. Preinterventional and postinterventional values were compared and related to occlusion rate. RESULTS: Postinterventional inflow showed a mean reduction of 37%, outflow of 51%, and rTTP a prolongation of 82%. Saccular aneurysm occlusion occurred if a reduction of at least 15% was achieved for inflow and 35% for outflow (sensitivity: 89%, specificity: 82%). Unchanged outflow and a slightly prolonged rTTP were associated with growth in one fusiform aneurysm. CONCLUSIONS: PCC allows visualization of flow alterations after FDS treatment, illustrating "flow diverting effects" by the TDC shape and indicating mainly aneurysmal outflow and lesser inflow changes. Quantifiable parameters (inflow, outflow, rTTP) can be obtained, thresholds for predicting aneurysm occlusion determined, and adverse flow modulations assumed. As a rapid intraprocedural tool, PCC might support the decision to implant more than one FDS. KEY POINTS: • After deployment of a flow-diverting stent, complete aneurysm occlusion is unpredictable. • Parametric colour coding offers new options for visualizing in vivo flow alterations non-invasively. • Quantifiable parameters, i.e., aneurysmal inflow/outflow can be obtained allowing prognostic stratification. • Rapid, intraprocedural application allows treatment monitoring, potentially contributing to patient safety.


Assuntos
Angiografia Digital/métodos , Implante de Prótese Vascular/instrumentação , Circulação Cerebrovascular/fisiologia , Aneurisma Intracraniano/cirurgia , Fluxo Sanguíneo Regional , Stents , Adulto , Idoso , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Desenho de Prótese
7.
J Neurol Neurosurg Psychiatry ; 85(3): 345-53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23606733

RESUMO

OBJECTIVE: Several families with characteristic features of hereditary myopathy with early respiratory failure (HMERF) have remained without genetic cause. This international study was initiated to clarify epidemiology and the genetic underlying cause in these families, and to characterise the phenotype in our large cohort. METHODS: DNA samples of all currently known families with HMERF without molecular genetic cause were obtained from 12 families in seven different countries. Clinical, histopathological and muscle imaging data were collected and five biopsy samples made available for further immunohistochemical studies. Genotyping, exome sequencing and Sanger sequencing were used to identify and confirm sequence variations. RESULTS: All patients with clinical diagnosis of HMERF were genetically solved by five different titin mutations identified. One mutation has been reported while four are novel, all located exclusively in the FN3 119 domain (A150) of A-band titin. One of the new mutations showed semirecessive inheritance pattern with subclinical myopathy in the heterozygous parents. Typical clinical features were respiratory failure at mid-adulthood in an ambulant patient with very variable degree of muscle weakness. Cytoplasmic bodies were retrospectively observed in all muscle biopsy samples and these were reactive for myofibrillar proteins but not for titin. CONCLUSIONS: We report an extensive collection of families with HMERF with five different mutations in exon 343 of TTN, which establishes this exon as the primary target for molecular diagnosis of HMERF. Our relatively large number of new families and mutations directly implies that HMERF is not extremely rare, not restricted to Northern Europe and should be considered in undetermined myogenic respiratory failure.


Assuntos
Doenças Genéticas Inatas/epidemiologia , Doenças Musculares/epidemiologia , Insuficiência Respiratória/epidemiologia , Adulto , Idoso , Conectina/genética , Exoma/genética , Feminino , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/patologia , Ligação Genética/genética , Predisposição Genética para Doença/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Doenças Musculares/genética , Doenças Musculares/patologia , Mutação/genética , Linhagem , Fenótipo , Insuficiência Respiratória/genética , Insuficiência Respiratória/patologia
8.
Eur Radiol ; 23(2): 521-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22895618

RESUMO

BACKGROUND: Quantifiable parameters to evaluate the effectiveness of flow diverters (FDs) are desirable. We measured time-density curves (TDCs) and calculated quantifiable parameters in the rabbit elastase-induced aneurysm model after stent (Neuroform [NF]) and FD (Pipeline embolisation device [PED]) treatment. METHODS: Sixteen rabbit elastase-induced aneurysms were treated with FD (n = 9) or NF (n = 5). Angiography was performed before and after treatment and TDCs were created. The time to peak (TTP), the full width at half maximum (FWHM) and the average slope of the curve which represent the inflow (IF) and outflow (OF) were calculated. RESULTS: Mean values before treatment were TTP = 0.8 s, FWHM = 1.2 s, IF = 153.5 and OF = -54.9. After PED treatment, the TTP of 1.8 s and FWHM of 47.8 s were extended. The IF was 31.2 and the OF was -11.5 and therefore delayed. The values after NF treatment (TTP = 1.1 s, FWHM = 1.8 s, IF = 152.9, OF = -33.2) changed only slightly. CONCLUSION: It was feasible to create TDCs in the rabbit aneurysm model. Parameters describing the haemodynamic effect of PED and NF were calculated and were different according to the type of device used. These parameters could possibly serve as predictive markers for aneurysm occlusion.


Assuntos
Aneurisma/diagnóstico por imagem , Aneurisma/terapia , Prótese Vascular , Aneurisma Intracraniano/terapia , Stents , Angiografia Digital , Animais , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Aneurisma Intracraniano/diagnóstico por imagem , Elastase Pancreática/efeitos adversos , Elastase Pancreática/farmacologia , Coelhos , Distribuição Aleatória , Sensibilidade e Especificidade , Artéria Subclávia , Fatores de Tempo , Grau de Desobstrução Vascular/fisiologia
9.
Interv Neuroradiol ; : 15910199221130236, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36184923

RESUMO

PURPOSE: Treating cerebral dural arteriovenous fistulas (dAVFs) by transarterial embolization is an established endovascular approach but no data exist regarding the utility of using the newly introduced microcatheters with extra-long detachable tip. Aim of our study was to evaluate the value of these microcatheters and, additionally, of combining them with the simplified pressure cooker technique. METHODS: Twenty-nine patients treated for dAVF with transarterial embolization were enrolled. In a subgroup of fifteen patients the simplified pressure cooker technique was additionally applied. Demographics and characteristics were collected for patients and dAVFs and procedural details reviewed. The association between covariates and binary-coded occlusion status was evaluated. RESULTS: Microcatheter navigation into the target pedicle as well as application of the simplified pressure cooker technique were successful in all cases. Complete dAVF occlusion was reached in 69.0% at a single stage. In case of complete dAVF occlusion, embolization via only one pedicle was enough. Subgroup analysis revealed a higher occlusion status (80%) if using the simplified pressure cooker technique than if not (57%) but reached not significance level. CONCLUSION: Using microcatheters with extra-long detachable tip for dAVF embolization seems to offer a safe and effective treatment option with exceptional high occlusion rate at a single stage. The high navigability facilitates catheterization of a single selected target pedicle that is often enough to reach complete dAVF occlusion. Combining these microcatheters with the simplified pressure cooker technique turned out to be safe and easy to handle and might allow an increasing dAVF occlusion rate.

10.
Eur Radiol ; 21(8): 1797-801, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21720943

RESUMO

OBJECTIVE: To demonstrate the feasibility of intravenous Flat Detector CT Angiography (FD-CTA) for visualisation of intracranial Flow Diverting Devices. Flow Diverting Devices are used increasingly for treatment of intracranial aneurysms. A close follow up is necessary because it becomes obvious that a significant proportion of aneurysms treated with these devices remain patent. A minimally invasive method is highly desirable. METHODS: In two patients treated with flow diverters a Flat Detector CT (FD-CT) with intravenous contrast medium application was performed. Post-processing was performed using commercially available software. RESULTS: In both patients the lumen of the device and the lumen of the aneurysm could be clearly evaluated. Some beam hardening artefacts due to the marker wires of the device were obvious. CONCLUSION: Flat Detector CT with intravenous contrast material application to evaluate flow-diverting devices seems to be feasible. Further studies are necessary to perform comparative evaluation of FD-CTA with angiography and other techniques like MRA or conventional CT angiography.


Assuntos
Angiografia Cerebral/métodos , Circulação Cerebrovascular , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Tomografia Computadorizada por Raios X/métodos , Idoso , Angiografia Digital , Estudos de Viabilidade , Feminino , Humanos , Imageamento Tridimensional , Interpretação de Imagem Radiográfica Assistida por Computador
11.
Rofo ; 191(9): 827-835, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30665249

RESUMO

PURPOSE: The collateral status can be defined not only by its morphological extent but also by the velocity of collateral filling characterized by the relative filling time delay (rFTD). The aim of our study was to compare different methods of noninvasive visualization of rFTD derived from 4D-CT angiography (4D-CTA) with digital substraction angiography (DSA) and to investigate the correlation between functional and morphological collateral status on timing-invariant CTA. MATERIALS AND METHODS: 50 consecutive patients with acute occlusion in the M1 segment who underwent DSA for subsequent mechanical recanalization after multimodal CT were retrospectively analyzed. 4D-CTA data were used to assess the relative filling time delay between the A1 segment of the affected hemisphere and the sylvian branches distal to the occluded M1 segment using source images (4D-CTA-SI) and color-coded flow velocity visualization with prototype software (fv-CTA) in comparison to DSA. The morphological extent of collaterals was assessed on the basis of the Collateral Score (CS) on temporal maximum intensity projections (tMIP) derived from CT perfusion data. RESULTS: There was very good correlation of rFTD between fv-CTA and DSA (n = 50, r = 0.9, p < 0.05). Differences of absolute rFTD values were not significant. 4D-CTA-SI and DSA also showed good correlation (n = 50, r = 0.6, p < 0.05), but mean values of rFTD were significantly different (p < 0.05). rFTD derived from fvCTA and CS derived from timing-invariant CTA showed a negative association (R = - 0.5; P = 0.000). In patients with a favorable radiological outcome defined by a TICI score of 2b or 3, there was a significant negative correlation of CS and mRS at 3 months (R = - 0.4, P = 0.006). CONCLUSION: Collateral status plays an important role in the outcome in stroke patients. rFTD derived from 4D-CTA is a suitable parameter for noninvasive imaging of collateral velocity, which correlates with the morphological extent of collaterals. Further studies are needed to define valid thresholds for rFTD and to evaluate the diagnostic and prognostic value. KEY POINTS: · Collateral supply in anterior circulation stroke can be defined by the velocity of collateral filling. · Relative filling time delay (rFTD) can serve for quantitative measurement of collateral flow and correlates with the morphological extent of collaterals. · 4D-CTA is a suitable noninvasive imaging technique. CITATION FORMAT: · Muehlen I, Kloska SP, Gölitz P et al. Noninvasive Collateral Flow Velocity Imaging in Acute Ischemic Stroke: Intraindividual Comparison of 4D-CT Angiography with Digital Subtraction Angiography. Fortschr Röntgenstr 2019; 191: 827 - 835.


Assuntos
Angiografia Digital , Velocidade do Fluxo Sanguíneo/fisiologia , Isquemia Encefálica/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Circulação Colateral/fisiologia , Tomografia Computadorizada Quadridimensional , Humanos , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Interv Neuroradiol ; 25(6): 655-663, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31296064

RESUMO

BACKGROUND: The recent growth of neuro-endovascular treatment has rekindled interest in the use of angiographic techniques for flow assessment. Aneurysm treatment with flow diverters is particularly amenable to such analysis. We analyze contrast time-density curves - recorded within aneurysms before (pre) and immediately after (post) flow diverter implantation to estimate six-month treatment outcomes. METHODS: Fifty-six patients with 65 aneurysms were treated with flow diverters at two institutions. A region of interest was drawn around the aneurysm perimeter in image sequences taken both pre and post angiography, and the temporal variation in grayscale intensity within the aneurysm (time-density curve) was recorded. Eleven parameters were quantified from each time-density curve. Aneurysm occlusion status was recorded six months post treatment. The change in parameters from pre to post treatment was statistically evaluated between aneurysm occluded and non-occluded groups. RESULTS: Of the 11 parameters, eight were significantly different before and immediately after flow diversion. Considering the entire data set, none of the parameters was statistically different between the occluded and non-occluded groups. However, subgroup analyses showed that four variables were significantly different between the aneurysm occluded and non-occluded groups. The sensitivity of these variables to predict aneurysm occlusion at six months ranged from 60% to 89%, while the specificity ranged from 55% to 70%. CONCLUSIONS: Device-induced intra-aneurysmal flow alterations quantified by simple aneurysmal time-density curves can potentially be used to predict long-term outcomes of flow diversion. Large multi-center studies will be required to confirm these findings. Patient-to-patient variability in coagulation may need to be incorporated for clinically relevant predictive values.


Assuntos
Prótese Vascular , Angiografia Cerebral , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Stents , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos , Procedimentos Cirúrgicos Vasculares
13.
Clin Neuroradiol ; 28(4): 501-507, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28812108

RESUMO

PURPOSE: Delayed cerebral ischemia (DCI) still remains a major complication after subarachnoid hemorrhage (SAH). The aim of our study was to evaluate whether flow analysis of admission digital subtraction angiography (DSA) using parametric color coding (PCC), a postprocessing algorithm, allows ultra-early identification of SAH patients at risk for developing subsequent symptomatic vasospasm. METHODS: In this study 52 patients who suffered SAH from aneurysm rupture, were retrospectively enrolled. Of the patients 26 developed DCI and angiographically proven cerebral vasospasm and 26 age, gender-and clinical status-matched SAH patients without DCI served as controls. Using PCC, the following flow parameters were calculated: cerebral circulation time (CirT), cortical relative time to peak (rTTP) and microvascular transit time (TT). RESULTS: Mean cerebral CirT and cortical rTTP were longer in the DCI group (6.42 s ± 1.54 and 3.16 s ± 0.86, respectively) than in the non-DCI group (5.77 s ± 1.86 and 3.11 s ± 1.41, respectively), but without statistical significance. The mean microvascular TT was statistically significantly (p = 0.04) longer in the DCI group (3.19 s ± 0.78) than in the non-DCI group (2.67 s ± 0.73). CONCLUSION: Angiographic flow analysis might be suitable for ultra-early detection and quantitative assessment of microcirculatory injury in SAH patients, predictive of developing subsequent DCI. Prolonged microvascular TT seems to be a significant independent factor positively associated with DCI development. Identifying SAH patients at risk for DCI ultra-early after ictus might contribute to initiate prophylactic therapies before clinical deterioration.


Assuntos
Angiografia Digital/métodos , Isquemia Encefálica/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Angiografia Cerebral/métodos , Interpretação de Imagem Assistida por Computador/métodos , Microcirculação/fisiologia , Hemorragia Subaracnóidea/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Isquemia Encefálica/fisiopatologia , Córtex Cerebral/irrigação sanguínea , Diagnóstico Precoce , Embolização Terapêutica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Valores de Referência , Estudos Retrospectivos , Hemorragia Subaracnóidea/fisiopatologia , Hemorragia Subaracnóidea/terapia , Vasoespasmo Intracraniano/diagnóstico por imagem , Vasoespasmo Intracraniano/fisiopatologia
14.
J Clin Neurosci ; 50: 199-202, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29366621

RESUMO

BACKGROUND AND PURPOSE: Parkinson's disease (PD) is characterised by neuropathological degenerative changes in the substantia nigra (SN). Our study aimed to evaluate whether high-resolution diffusion tensor-imaging (DTI) can detect anatomical biomarkers in early-stage PD, and has the potential to visualize asymmetry effects comparable to the 123I-FP-CIT SPECT (DaTSCAN). METHODS: Ten early-stage PD patients with mild disease severity and ten age- and gender-matched healthy controls were examined with a high-resolution DTI protocol at a 3 Tesla MRI scanner to assess fractional anisotropy (FA) values in the ventral, middle and dorsal region of SN. In addition, a subgroup of 5 PD patients underwent a DaTSCAN. RESULTS: PD subjects showed reduced FA values in all SN regions compared to controls, but post hoc analysis revealed a significant reduction (p = .032) in the dorsal region. There was no significant correlation between clinical data and FA values. Subgroup analysis of PD patients with asymmetric radioligand uptake in the DaTSCAN demonstrated also significant asymmetric FA values (p = .027) in the dorsal region of SN. CONCLUSIONS: Our results provide preliminary evidence that high-resolution DTI can detect in early-stage PD patients with mild disease severity an anatomical biomarker in the dorsal region of SN, indicating microstructural disorganization. This biomarker, discriminating potentially in vivo between patients and healthy people, could be valuable for early PD diagnosis. If asymmetric radioligand uptake in the DaTSCAN was present, also asymmetry effects in the dorsal region of SN were obtained by DTI. These findings might contribute to improve effectiveness in diagnosing and monitoring PD.


Assuntos
Imagem de Tensor de Difusão/métodos , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Substância Negra/patologia
15.
Clin Neuroradiol ; 28(4): 545-551, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28477180

RESUMO

OBJECTIVE: To illustrate the added value of flat-detector computed tomography angiography with intravenous contrast media injection (intravenous FDCTA) in the evaluation of complex A1/A2/AcomA aneurysms. PATIENTS AND METHODS: We retrospectively reviewed 15 patients with ruptured aneurysms. In each patient, an intravenous FDCTA was performed and its diagnostic value investigated. RESULTS: In all patients, FDCTA contributed relevant additional information concerning the anatomy of the A1/A2/AcomA complex and the relationship of the aneurysm neck to these vascular structures, which could not be gained by 2D- and 3D-DSA, and changed the management in 33% of the patients (5 out of 15). In an additional 5 cases, knowledge of the detailed anatomy was helpful to plan the exact stent position. CONCLUSION: In case of complex A1/A2/AcomA aneurysms, intravenous FDCTA is an effective option to visualize the exact location of the aneurysm neck and the relationship between the aneurysm and the adjacent vessels. Thus, it is of significant added value in the precise planning of a therapeutic strategy.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Iopamidol/análogos & derivados , Doença Aguda , Idoso , Angiografia Digital , Meios de Contraste/administração & dosagem , Embolização Terapêutica , Feminino , Humanos , Injeções Intravenosas , Aneurisma Intracraniano/terapia , Iopamidol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Stents
16.
Front Med (Lausanne) ; 4: 113, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28770205

RESUMO

Fungal infections of the central nervous system (CNS) frequently occur in immunosuppressed patients. Here, we describe the case of an immunocompetent 64-year-old man who presented with diplopia, right-sided hemiparesis, and a mild headache after cleaning and replacing nesting boxes of wild birds during the preceding months. Lumbar puncture revealed pleocytosis, elevated protein, and lactate levels in the cerebrospinal fluid (CSF). Initial imaging showed ischemia in the left thalamus and an enlargement of the sellar region. Antibiotic treatment and corticosteroids led to an initial improvement but was followed by rapid deterioration. Antibiotic treatment was modified and antifungal therapy was added. Eighteen days after admission, the patient died from a subarachnoid hemorrhage resulting from the rupture of a fusiform aneurysm of the basilar artery. Microbiological culture of CSF was negative, but a positive galactomannan assay suggested fungal infection which was corroborated by detection of Aspergillus fumigatus DNA in pan-fungal PCR and sequencing. The presence of septated hyphae in the wall of the basilar artery confirmed the diagnosis of a mycotic aneurysm caused by hyphomycetal infection. In addition, brain autopsy revealed the presence of an invasive adrenocorticotrophic hormone-producing pituitary adenoma with arrosion of the sellar bone. This process and its invasiveness likely facilitated the spread of the fungal pathogen from the sphenoid sinus to the dura mater and finally led to cerebral angioinvasion. Our case demonstrates the challenge to timely diagnose and effectively treat aspergillosis as a cause of CNS infection also in apparently immunocompetent patients. The potential of assays detecting fungal antigens and of PCR to facilitate a timely diagnosis is discussed.

17.
J Neurol Sci ; 375: 76-79, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28320193

RESUMO

Progressive multifocal leukoencephalopathy (PML) is a rare, opportunistic and often fatal disease of the CNS which may occur under immunosuppression in transplant patients. Brain stem PML is associated with a particularly bad prognosis. Here, we present a case of a renal transplant patient treated with mycophenolate mofetil (MMF) and tacrolimus who developed brain stem PML with limb ataxia, dysarthria and dysphagia. Diagnosis was established by typical MRI features and detection of JCV-DNA in the CSF. Immune reconstitution after stopping MMF and tacrolimus led to a complete and sustained remission of symptoms with improvement of the brain stem lesion over a follow-up over 20months. In summary, early detection of PML and consequent treatment may improve neurological outcomes even in brain stem disease with a notorious bad prognosis.


Assuntos
Tronco Encefálico/patologia , Transplante de Rim/efeitos adversos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/etiologia , Leucoencefalopatia Multifocal Progressiva/patologia , Adulto , Antibióticos Antituberculose/uso terapêutico , Tronco Encefálico/diagnóstico por imagem , DNA/líquido cefalorraquidiano , Diagnóstico Precoce , Feminino , Humanos , Imunossupressores/uso terapêutico , Vírus JC/genética , Vírus JC/imunologia , Falência Renal Crônica/tratamento farmacológico , Falência Renal Crônica/cirurgia , Leucoencefalopatia Multifocal Progressiva/líquido cefalorraquidiano , Imageamento por Ressonância Magnética , Ácido Micofenólico/uso terapêutico , Tacrolimo/uso terapêutico
19.
Interv Neuroradiol ; 22(1): 76-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26515700

RESUMO

OBJECT: Our study aimed to evaluate the efficiency of flow-diverting stents (FDS) in treating unruptured, intradural dissecting aneurysms of the vertebral artery (VADAs). Additionally, the effect of FDS on the aneurysmal flow pattern was investigated by performing in vivo flow analysis using parametric color coding (PCC). METHODS: We evaluated 11 patients with unruptured, intradural VADAs, treated with FDS. Pre- and postinterventional DSA-series were postprocessed by PCC, and time-density curves were calculated. The parameters aneurysmal inflow-velocity, outflow-velocity and relative time-to-peak (rTTP) were calculated. Pre- and postinterventional values were compared and correlated with the occlusion rate after six months. RESULTS: Follow-up DSA detected 10 aneurysms occluded, meaning an occlusion rate of 91%. No procedure-related morbidity and mortality was found. Flow analyses revealed a significant reduction of aneurysmal inflow- velocity and prolongation of rTTP after FDS deployment. Concerning aneurysm occlusion, the postinterventional outflow-velocity turned out to be a marginally statistically significant predictor. A definite threshold value (-0.7 density change/s) could be determined for the outflow-velocity that allows prediction of complete aneurysm occlusion with high sensitivity and specificity (100%). CONCLUSIONS: Using FDS can be considered an efficient and safe therapy option in treating unruptured, intradural VADA. From in vivo flow analyses the postinterventional aneurysmal outflow-velocity turned out to be a potential predictor for later complete aneurysm occlusion. Here, it might be possible to determine a threshold value that allows prediction of aneurysm occlusion with high specificity and sensitivity. As fast, applicable and easy-to-handle tool, PCC could be used for procedural monitoring and might contribute to further treatment optimization.


Assuntos
Circulação Cerebrovascular , Procedimentos Endovasculares/instrumentação , Stents , Dissecação da Artéria Vertebral/fisiopatologia , Dissecação da Artéria Vertebral/terapia , Idoso , Dissecção Aórtica/cirurgia , Dissecção Aórtica/terapia , Angiografia/métodos , Velocidade do Fluxo Sanguíneo , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Resultado do Tratamento , Dissecação da Artéria Vertebral/diagnóstico por imagem
20.
Neuroradiol J ; 29(2): 99-105, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26932163

RESUMO

OBJECTIVE: Recent studies have shown the efficacy of mechanical thrombectomy in acute ischemic stroke. We sought to identify prognostic parameters for clinical and radiological outcome after mechanical thrombectomy. METHODS: In 34 patients (age 72 ± 13 years, 64.7% women) with acute occlusion of the distal ICA and/or M1 segment who were treated with mechanical thrombectomy, the Spearman correlation was performed to assess potential prognostic outcome parameters (age, NIHSS, ASPECT, thrombus length (TL), clot burden score (CBS), relative filling time delay (rFTD), time to recanalization (TTR) and TICI score). The modified Rankin scale (mRS) and the Alberta Stroke Program Early CT (ASPECT) score were used for clinical and radiological outcome, respectively. Receiver operating characteristic (ROC) analysis was performed to assess parameters predicting favorable clinical (ΔmRS ≤ 2) and radiological outcome (ΔASPECT ≤ 2). RESULTS: Variables associated with favorable clinical outcome included NIHSS, TL, TTR and TICI score (p ≤ 0.01) with NIHSS ≤ 15 (p = 0.001, area under the curve (AUC) 0.87), TL ≤ 2 cm (p = 0.017, AUC 0.75), TTR ≤ 231 min (p = 0.001 AUC 0.88) and TICI ≥ 2b (p = 0.050, AUC 0.70). Shorter TTR and higher TICI scores were associated with favorable radiological outcome (p < 0.001) with TTR ≤ 224 min (p = 0.023, AUC 0.77) and TICI ≥ 2b (p = 0.000, AUC 0.86). CONCLUSION: Fast and complete recanalization is essential to achieve a favorable radiological and functional outcome after mechanical thrombectomy in acute ischemic stroke. Age, CBS and collateral supply play a subordinate role.


Assuntos
Trombólise Mecânica/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Resultado do Tratamento , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Angiografia Cerebral , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Índice de Gravidade de Doença , Tomógrafos Computadorizados
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