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1.
Radiol Med ; 125(9): 838-850, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32671554

RESUMO

4D Flow is an emerging MR technique enabling three-dimensional and cardiac phase-resolved flowmetry with ECG-gated phase-contrast MRI that increased the speed of data acquisitions, accuracy and robustness. The method is promoting researches in areas that have not been fully addressed before in the cardiovascular system, such as flowmetry of the bloodstream across the valves, within the heart chambers, complexed flow dynamics such as vortex, helical or retrograde. Wall shear stress and other potential biomarkers derived from 4D Flow are known to be related to vascular wall diseases such as atherosclerosis. In this review, fundamental concepts of 4D Flow technique and post-processing, benefits and limitations as well as its clinical applications are discussed, and the importance of quality control and validation of the method is emphasized. New ideas inspired by 4D Flow can help clinicians and MR scientists further understand the role of flow dynamics in health sciences, diseases and various aspects of cardiovascular physiology.


Assuntos
Circulação Coronária/fisiologia , Imagem Cinética por Ressonância Magnética/métodos , Velocidade do Fluxo Sanguíneo , Eletrocardiografia/métodos , Humanos , Hidrodinâmica , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/métodos , Fluxo Sanguíneo Regional/fisiologia , Resistência ao Cisalhamento/fisiologia
2.
Medicine (Baltimore) ; 99(22): e20503, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481470

RESUMO

To investigate the feasibility of 3D arterial spin labeling (ASL) as an alternative to dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for the qualitative and quantitative evaluation of nasopharyngeal carcinoma (NPC) perfusion.Fifty-two newly diagnosed NPC patients underwent 3D ASL and DCE-MRI scans on a 3.0-T MRI system. The visual qualitative evaluation of the NPC perfusion level was scored from 0 to 3 (0 = no contrast to normal peripheral soft tissue, 3 = pronounced contrast to normal peripheral soft tissue). The visual evaluation of the NPC outline was scored from 0 to 2 (0 = very vague outline, 2 = clear outline). Comparisons of the ASL-derived blood flow (BF) with the DCE-MRI-derived positive enhancement integral, maximum slope of increase, maximum slope of decrease, and time to peak (TTP) were conducted between NPC and non-NPC areas with independent samples t-tests. The diagnostic performance of these parameters was assessed by receiver operating characteristic curve analysis. The correlations between ASL BF and DCE parameters were assessed by Spearman correlation analysis.There was no difference in the visual scores of the NPC perfusion level between the 2 perfusion methods (P= .963). ASL had a lower visual score for describing the outline of NPC than DCE-MRI (P < .001). The ASL and DCE parameters of the NPC areas were significantly different from those of the non-NPC areas (P < .001). The ASL BF showed the largest area under the receiver operating characteristic curve (AUC) of 0.936 for identifying NPC. When all NPC and non-NPC areas were taken into account, significant correlations were observed between the ASL BF and the DCE parameters positive enhancement integral (r = 0.503, P < .001), maximum slope of increase (r = 0.616, P < .001), maximum slope of decrease (r = 0.380, P < .001), and TTP (r = -0.601, P < .001).3D ASL could reveal the hyperperfusion of NPC in a qualitative and quantitative manner without using contrast agent. Additionally, the ASL BF correlated significantly with the semiquantitative DCE-MRI parameters.


Assuntos
Angiografia por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Meios de Contraste , Estudos de Viabilidade , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Marcadores de Spin
3.
PLoS One ; 15(6): e0233992, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492059

RESUMO

INTRODUCTION: Susceptibility weighted imaging (SWI) is a very sensitive technique that often depicts prominent focal veins (PFV) in patients with acute migraine with aura (MwA). Interpretation of visual venous asymmetry (VVA) between brain hemispheres on SWI may help support the clinical diagnosis of MwA. Our goal was to develop an automated algorithm for segmentation and quantification of cerebral veins using SWI. MATERIALS AND METHODS: Expert readers visually evaluated SWI of patients with acute MwA for VVA. Subsequently a fully automated algorithm based on 3D normalization and 2D imaging processing using SPM and MATLAB image processing software including top-hat transform was used to quantify cerebral veins and to calculate volumetric differences between hemispheres. RESULTS: Fifty patients with MwA were examined with SWI. VVA was present in 20 of 50 patients (40%). In 95% of patients with VVA, the fully automated calculation agreed with the side that visually harboured more PFV. Our algorithm showed a sensitivity of 95%, specificity of 90% and accuracy of 92% for detecting VVA. Patients with VVA had significantly larger vein volume on the hemisphere with more PFV compared to patients without (15.90 ± 5.38 ml vs 11.93 ± 5.31 ml; p = 0.013). The mean difference in venous volume between hemispheres in patients with VVA was larger compared to patients without VVA (16.34 ± 7.76% vs 4.31 ± 3.26% p < 1E-10). The average time between aura onset and SWI correlated negatively with venous volume of the dominant brain hemisphere (r = -0.348; p = 0.038). CONCLUSION: A fully automated algorithm can accurately identify and quantify cerebral venous distribution on SWI. Absolute quantification may be useful for the future assessment of patients with suspected diseases, which may be associated with a unilateral abnormal degree of venous oxygenation.


Assuntos
Algoritmos , Veias Cerebrais/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Angiografia por Ressonância Magnética/métodos , Enxaqueca com Aura/diagnóstico , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
4.
J Card Surg ; 35(7): 1736-1739, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32497341

RESUMO

The impact of the coronavirus disease 2019 (COVID-19) pandemic in New York City (NYC) is dramatic. COVID-19 cases surged, hospitals expanded to meet capacity, and NYC remains the global epicenter of this pandemic. During this unprecedented time, a young woman with known Marfan syndrome presented with an acute complicated type B aortic dissection to our Aortic Center. Using the provisional extension to induce a complete attachment technique, we treated this patient and quickly discharged her the next day to decrease the risk of COVID-19 infection. Her progress was monitored using frequent phone calls and one office visit at two weeks.


Assuntos
Aneurisma Dissecante/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Infecções por Coronavirus/epidemiologia , Procedimentos Endovasculares/métodos , Pneumonia Viral/epidemiologia , Dor Abdominal/diagnóstico , Dor Abdominal/etiologia , Doença Aguda , Adulto , Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/etiologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/etiologia , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Infecções por Coronavirus/diagnóstico , Infecção Hospitalar/prevenção & controle , Feminino , Seguimentos , Humanos , Tempo de Internação , Angiografia por Ressonância Magnética/métodos , Síndrome de Marfan/complicações , Síndrome de Marfan/diagnóstico , Cidade de Nova Iorque , Pandemias , Pneumonia Viral/diagnóstico , Índice de Gravidade de Doença , Resultado do Tratamento
5.
Radiol Clin North Am ; 58(4): 707-719, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32471539

RESUMO

Pulmonary vascular assessment commonly relies on computed tomography angiography (CTA), but continued advances in magnetic resonance angiography have allowed pulmonary magnetic resonance angiography (pMRA) to become a reasonable alternative to CTA without exposing patients to ionizing radiation. pMRA allows the evaluation of pulmonary vascular anatomy, hemodynamic physiology, lung parenchymal perfusion, and (optionally) right and left ventricular function with a single examination. This article discusses pMRA techniques and artifacts; performance in commonly encountered pulmonary vascular diseases, specifically pulmonary embolism and pulmonary hypertension; and recent advances in both contrast-enhanced and noncontrast pMRA.


Assuntos
Hipertensão Pulmonar/diagnóstico por imagem , Angiografia por Ressonância Magnética , Embolia Pulmonar/diagnóstico por imagem , Adolescente , Idoso , Artefatos , Feminino , Humanos , Lactente , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Radiol Clin North Am ; 58(4): 797-813, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32471545

RESUMO

MR angiography is a flexible imaging technique enabling morphologic assessment of mesenteric arterial and venous vasculature. Conventional gadolinium-based contrast media and ferumoxytol are used as contrast agents. Ferumoxytol, an intravenous iron replacement therapy approved by the US Food and Drug Administration for iron deficiency anemia, is an effective and well tolerated blood pool contrast agent. The addition of 4D flow MR imaging enables a functional assessment of the arterial and venous vasculature; when coupled with a meal challenge, the severity of mesenteric arterial stenosis is well appreciated. Noncontrast MR angiographic techniques are useful for evaluating suspected mesenteric ischemia.


Assuntos
Angiografia por Ressonância Magnética/métodos , Mesentério/irrigação sanguínea , Mesentério/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Meios de Contraste , Óxido Ferroso-Férrico , Humanos , Síndrome do Ligamento Arqueado Mediano/diagnóstico por imagem , Doenças Vasculares/diagnóstico por imagem
7.
AJR Am J Roentgenol ; 215(1): 206-214, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374667

RESUMO

OBJECTIVE. The purpose of this article is to summarize current common techniques and indications for pediatric abdominopelvic MR angiography and strategies for optimizing them to achieve successful outcomes. We also discuss newer MR angiography techniques, including whole-body imaging and blood pool contrast agents, as well as various approaches to reducing the need for anesthesia in pediatric MRI. CONCLUSION. Pediatric body vascular imaging presents a unique set of challenges that require a tailored approach. Emerging pediatric abdominopelvic MR angiography techniques hold promise for continued improvement in pediatric body MR angiography.


Assuntos
Abdome/irrigação sanguínea , Abdome/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Doenças Vasculares/diagnóstico por imagem , Adolescente , Criança , Meios de Contraste , Humanos , Aumento da Imagem/métodos , Imagem Corporal Total
9.
Medicine (Baltimore) ; 99(18): e19742, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358348

RESUMO

Hemodynamic changes occurring at the segments of arterial bifurcations, up and down stream of stenotic vessels appear to play a critical role in the development of atherosclerosis. Therefore, we hypothesized that basilar artery (BA) geometry may be related to the distribution of atherosclerotic plaque.In this retrospective cross-sectional study, all patients hospitalized with ischemic stroke and intracranial atherosclerotic disease were sifted from March 2017 to October 2017. Sixty-seven patients with intracranial atherosclerotic disease (39 with and 28 without BA atherosclerosis) were analyzed. Magnetic resonance imaging, magnetic resonance angiography, and high-resolution black-blood MRI were performed within 7 days after symptoms onset. BA tortuosity, plaque location, and plaque enhancement were assessed. Plaque burden and vascular remodeling were measured.Of the 39 patients with BA atherosclerosis, plaques preferred to be formed at the inner arc than the outer arc (27/39, 69% vs 12/39, 31%) in the tortuous BA. In addition, patients with BA plaque had a greater vascular tortuosity compared with those without plaque (113.1 ±â€Š10.2 vs 107 ±â€Š4.6; P = .034). Finally, patients with apparent BA plaque had greater plaque enhancement (14/21, 67% vs 5/18, 28%; P = .017) and plaque burden (0.76 ±â€Š0.15 vs 0.70 ±â€Š0.09; P = .036) compared with those with minimal plaque.Plaque may be more likely to form at the inner arc of tortuous BA with atherosclerotic disease, and increased BA tortuosity is associated with its likelihood to form plaque.


Assuntos
Aterosclerose/patologia , Artéria Basilar/patologia , Placa Aterosclerótica/patologia , Acidente Vascular Cerebral/patologia , Idoso , Aterosclerose/diagnóstico por imagem , Artéria Basilar/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Remodelação Vascular
10.
PLoS One ; 15(4): e0232372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348366

RESUMO

OBJECTIVES: Non-Cartesian Spiral readout can be implemented in 3D Time-of-flight (TOF) MR angiography (MRA) with short acquisition times. In this intra-individual comparison study we evaluated the clinical feasibility of Spiral TOF MRA in comparison with compressed sensing accelerated TOF MRA at 1.5T for intracranial vessel imaging as it has yet to be determined. MATERIALS AND METHODS: Forty-four consecutive patients with suspected intracranial vascular disease were imaged with two Spiral 3D TOFs (Spiral, 0.82x0.82x1.2 mm3, 01:32 min; Spiral 0.8, 0.8x0.8x0.8 mm3, 02:12 min) and a Compressed SENSE accelerated 3D TOF (CS 3.5, 0.82x0.82x1.2 mm3, 03:06 min) at 1.5T. Two neuroradiologists assessed qualitative (visualization of central and peripheral vessels) and quantitative image quality (Contrast Ratio, CR) and performed lesion and variation assessment for all three TOFs in each patient. After the rating process, the readers were questioned and representative cases were reinspected in a non-blinded fashion. For statistical analysis, the Friedman and Nemenyi post-hoc test, Kendall W tests, repeated measure ANOVA and weighted Cohen's Kappa tests were used. RESULTS: The Spiral and Spiral 0.8 outperformed the CS 3.5 in terms of peripheral image quality (p<0.001) and performed equally well in terms of central image quality (p>0.05). The readers noted slight differences in the appearance of maximum intensity projection images. A good to high degree of interstudy agreement between the three TOFs was observed for lesion and variation assessment (W = 0.638, p<0.001 -W = 1, p<0.001). CR values did not differ significantly between the three TOFs (p = 0.534). Interreader agreement ranged from good (K = 0.638) to excellent (K = 1). CONCLUSIONS: Compared to the CS 3.5, both the Spiral and Spiral 0.8 exhibited comparable or better image quality and comparable diagnostic performance at much shorter acquisition times.


Assuntos
Angiografia Cerebral/métodos , Transtornos Cerebrovasculares/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral/economia , Estudos de Viabilidade , Feminino , Humanos , Imageamento Tridimensional/economia , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/economia , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
11.
Radiol Med ; 125(9): 851-863, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32266692

RESUMO

OBJECTIVES: To evaluate the association of magnetic resonance diffusion-weighted imaging (DwI) and dynamic contrast-enhanced perfusion-weighted imaging (DCE-PwI) with a temporal resolution of 5 s, wash-in < 120 s, and wash-out ratio > 30% in the evaluation of salivary glands neoplasms. METHODS: DwI and DCE-PwI of 92 salivary glands neoplasms were assessed. The apparent diffusion coefficient (ADC) was calculated by drawing three regions of interest with an average area of 0.30-0.40 cm2 on three contiguous axial sections. The time/intensity curve was generated from DCE-PwI images by drawing a region of interest that included at least 50% of the largest lesion section. Vessels, calcifications, and necrotic/haemorrhagic or cystic areas within solid components were excluded. The association of ADC ≥ 1.4 × 10-3 mm2/s with type A curves (progressive wash-in) and ADC 0.9-1.4 × 10-3 mm2/s with type C curves (rapid wash-in/slow wash-out) were tested as parameters of benignity and malignancy, respectively. Type B curve (rapid wash-in/rapid wash-out) was not used as a reference parameter. RESULTS: ADC ≥ 1.4 × 10-3 mm2/s and type A curves were observed only in benign neoplasms. ADC of 0.9-1.4 × 10-3 mm2/s and type C curves association showed specificity of 94.9% and positive predictive value of 81.8% for epithelial malignancies. The association of ADC < 0.9 × 10-3 mm2/s with type B and C curves showed diagnostic accuracy of 94.6% and 100% for Warthin tumour and lymphoma, respectively. CONCLUSIONS: ADC ≥ 1.4 × 10-3 mm2/s and type A curves association was indicative of benignity. Lymphomas exhibited ADC < 0.7 × 10-3 mm2/s and type C curves. The association of ADC < 0.9 × 10-3 mm2/s and type B and C curves had accuracy 94.6% and 88.5% for Warthin tumour and epithelial malignancies, respectively.


Assuntos
Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Adenolinfoma/diagnóstico por imagem , Adenoma Pleomorfo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Linfoma/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/diagnóstico por imagem , Estudos Retrospectivos , Adulto Jovem
13.
Br J Radiol ; 93(1113): 20190764, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32302209

RESUMO

Stable ischemic heart disease remains a major cause of morbidity and mortality. Although there are multiple imaging modalities to diagnose and/or assist in the clinical management, the most cost-effective approach remains unclear. We reviewed the relevant and recent evidence-based clinical studies and trials to suggest the most cost-effective approach to stable ischemic heart disease. The limitations of these studies are discussed. Incorporating the results of recent multicenter trials, we suggest that for appropriate patients with coronary artery disease with any degree of stenosis or presence of coronary calcium, optimal medical therapy may be most cost-effective. Invasive coronary angiography and/or coronary revascularization would be primarily for non-responders or >/=50% left main stenosis. Stress cardiac magnetic imaging would be performed for those patients with non-diagnostic coronary CT angiography from motion and non-responders from optimal medical therapy in non-diagnostic coronary CT angiography group from high coronary calcium. These paths seem to be safe and cost-effective but requires modeling for confirmation.


Assuntos
Isquemia Miocárdica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/economia , Angiografia Coronária/economia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/terapia , Análise Custo-Benefício , Humanos , Angiografia por Ressonância Magnética/economia , Angiografia por Ressonância Magnética/métodos , Estudos Multicêntricos como Assunto , Isquemia Miocárdica/terapia , Revascularização Miocárdica/economia , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia
14.
Stroke ; 51(5): 1451-1457, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32299322

RESUMO

Background and Purpose- Reversible cerebral vasoconstriction syndrome (RCVS) has a unique temporal course of vasoconstriction. Blood-brain barrier (BBB) breakdown is part of the pathophysiology of RCVS, but its temporal course is unknown. We aimed to investigate the temporal profile of BBB breakdown and relevant clinical profiles in a large sample size. Methods- In this prospective observatory bicenter study, patients who underwent contrast-enhanced fluid-attenuated inversion recovery magnetic resonance imaging within 2 months from onset were included. The presence and extent of BBB breakdown were evaluated using contrast-enhanced fluid-attenuated inversion recovery magnetic resonance imaging. Contrast-enhanced fluid-attenuated inversion recovery magnetic resonance imaging data were analyzed using a semiautomated segmentation technique to quantitatively measure the area of Gadolinium leakage into cerebrospinal fluid space. The univariable and multivariable linear regressions were performed to investigate the independent effect of time from onset with adjustment for other covariates. Results- In the 186 patients with angiogram-proven RCVS included in this analysis, BBB breakdown was observed in 52.6%, 56.8%, 30.3%, 40.0%, and 23.8% in the first, second, third, fourth, and ≥fifth week after onset. The extent of BBB breakdown peaked at first and second week, whereas the peak of vasoconstriction was observed at the third week after onset. Multivariable analysis showed the second week from onset (ß, 3.35 [95% CI, 0.07-6.64]; P=0.046) and blood pressure surge (ß, 3.84 [95% CI, 1.75-5.92]; P<0.001) were independently associated with a greater extent of BBB breakdown. A synergistic effect of time from onset and blood pressure surge was found (P for interaction=0.006). Conclusions- Frequency and extent of BBB breakdown are more prominent during the early stage in patients with RCVS, with an earlier peak than that of vasoconstriction. The temporal course of BBB breakdown may provide a pathophysiologic background of the temporal course of neurological complications of RCVS.


Assuntos
Barreira Hematoencefálica/patologia , Transtornos Cerebrovasculares/patologia , Vasoconstrição/fisiologia , Vasoespasmo Intracraniano/patologia , Transtornos Cerebrovasculares/complicações , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Vasoespasmo Intracraniano/diagnóstico , Vasoespasmo Intracraniano/etiologia
15.
J Clin Neurosci ; 76: 87-99, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32284290

RESUMO

INTRODUCTION: Cranial dural arteriovenous fistulas (DAVFs) are rare vascular lesions that often harbour complex angio-architectural features. This subtype of DAVF may require multiple, multimodality, or hybrid treatments. In this paper we aim to identify specific angio-architectural features that are present in complex cranial DAVFs and we report our series with respect to treatment modalities and outcomes. METHODS: Twenty-five cranial Borden type II and III cranial DAVFs were treated at our Institution from 2013 to 2017. We classified nine (36%) as complex based on specific angio-architectural features. Treatment strategies were based on fistula location, angiographic features and patient's presenting condition. Phone interviews were used to confirm outcome at 6 and 12 months. RESULTS: Four patients (45%) presented with acute hydrocephalus, and 3 (33%) with intracranial hemorrhage. Multiple and combined treatment sessions were needed for all complex DAVFs. Five patients required 2 endovascular procedures each. One patient had 2 surgeries. The first line of treatment was endovascular in 6 cases (67%) and surgery in 3 (33%). Two treatment-related (22%) complications occurred. Complete disconnection was achieved in 5 out of 9 patients (55%). Two patients with an incomplete disconnection refused further treatment and were well at last follow up, with a partially treated fistula and persistent CVR. The other 3 patients concluded treatment after the end of our data collection period. At 1 year, 7/9 patients had stable or improved clinical symptoms, and 8/9 patients had GOS of 4 or 5. CONCLUSIONS: Complex cranial DAVF often require a multidisciplinary approach and multiple treatment sessions should be expected. Specific angio-architectural features that increase DAVF complexity include multiple arterial feeders, especially transosseous or pial, reflux into multiple cortical veins, sinus occlusion/entrapment, venous aneurysms, segmental stenosis, medial or deep location, and association with the deep venous system.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/patologia , Malformações Vasculares do Sistema Nervoso Central/terapia , Idoso , Angiografia Cerebral/métodos , Terapia Combinada , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
16.
Br J Radiol ; 93(1110): 20190830, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32208976

RESUMO

OBJECTIVES: To compare the performance of arterial spin labelling (ASL) in evaluating arteriovenous malformations (AVMs) against the current gold standard of catheter angiography. METHODS: We systematically reviewed the published literature using EMBASE and Medline. We included studies that compared ASL to catheter angiography in the assessment of AVMs in three outcome domains: detection, angioarchitectural and haemodynamic features. RESULTS: From 314 unique citations, 19 studies representing 289 patients with intracranial AVMs met our inclusion criteria. We did not pool data due to marked heterogeneity in study outcome measures. Seven studies showed high diagnostic performance of ASL in identifying arterial feeders, with sensitivity ranging from 84.6 to 100% and specificity ranging from 93.3 to 100%. Six studies showed strong ability in detecting arteriovenous shunting, with sensitivity ranging from 91.7 to 100% and specificity ranging from 90 to 100%. Seven studies demonstrated that ASL could identify nidal location and size as well as catheter angiography, while five studies showed relatively poorer performance in delineating venous drainage. Two studies showed 100% sensitivity of ASL in the identification of residual or obliterated AVMs following stereotactic radiosurgery. CONCLUSIONS: Despite limitations in the current evidence base and technical challenges, this review suggests that ASL has a promising role in the work-up and post-treatment follow-up of AVMs. Larger scale prospective studies assessing the diagnostic performance of ASL are warranted. ADVANCES IN KNOWLEDGE: ASL demonstrates overall validity in the evaluation of intracranial AVMs.


Assuntos
Angiografia Cerebral/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Cateterismo/métodos , Circulação Cerebrovascular , Humanos , Sensibilidade e Especificidade , Marcadores de Spin
17.
AJR Am J Roentgenol ; 214(5): 1031-1041, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32130039

RESUMO

OBJECTIVE. The purpose of this article is to describe optimized techniques for successful thoracic MR angiography (MRA) in children and to review examples of commonly encountered conditions. CONCLUSION. Successful MRA in children relies on considering the specific child and condition being evaluated and making appropriate choices about the most suitable modality, the use of anesthesia, and the best MRA techniques to determine a diagnosis.


Assuntos
Angiografia por Ressonância Magnética/métodos , Doenças Torácicas/diagnóstico por imagem , Doenças Vasculares/diagnóstico por imagem , Criança , Meios de Contraste , Humanos
18.
Radiology ; 295(3): 542-549, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32208095

RESUMO

Background After acute myocardial infarction (AMI), reperfusion injury is associated with microvascular lesions and myocardial edema. Purpose To evaluate the performance of apparent diffusion coefficient (ADC) quantification compared with T1 and T2 values in the detection of acute myocardial injury. Materials and Methods In this prospective study conducted from June 2016 to November 2018, participants without a history of heart failure or cardiomyopathy were enrolled after undergoing reperfusion for their first AMI. Quantitative T1 and T2 mapping were performed with a 1.5-T MRI scanner and compared with a fast free-breathing acquisition technique for ADC mapping (approximate duration, 3 minutes; five slices; spin-echo cardiac diffusion acquisition; b values, 0 and 200 sec/mm2; six diffusion-encoding directions; five repetitions). Quantitative ADC and unenhanced T1 and T2 values were compared in infarct, border, and remote regions by using Welch analysis of variance with Games-Howell post hoc test for pairwise comparisons. Results Thirty-four participants with AMI underwent MRI an average of 5 days ± 1.9 (standard deviation) after reperfusion. Mean ADC was markedly high in the infarcted regions (2.32 × 10-3 mm2/sec; 95% confidence interval [CI]: 2.28, 2.36) and moderately high in the border regions (1.91 ×10-3 mm2/sec; 95% CI: 1.89, 1.94; P < .001). In remote regions, mean ADC (1.62 ×10-3 mm2/sec; 95% CI: 1.59, 1.64) was comparable to that measured in vivo in healthy volunteers. Within the same regions of interest, although the measures showed similar trends in infarct and remote regions for T1 (mean, 1332 mec [95% CI: 1296, 1368] vs 1045 msec [95% CI: 1034, 1056]; P < .001) and T2 (72 msec [95% CI: 69, 75] vs 50 msec [95% CI: 49, 51]; P < .001), the magnitude of the differences among regions was greater when using ADC. Normalized signal differences between infarct and remote regions showed that diffusion-weighted MRI depicted edema 5.1 (P < .001) and 3.5 (P < .001) times greater than did T1 and T2 maps, respectively. Conclusion Multislice cardiac diffusion-weighted images could be acquired in those with acute myocardial injury. Quantitative apparent diffusion coefficient mapping showed greater differences among remote regions and lesions than did T1 or T2 mapping. © RSNA, 2020 See also the editorial by Lloyd and Farris in this issue.


Assuntos
Edema/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Idoso , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
19.
PLoS One ; 15(2): e0229024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053703

RESUMO

OBJECTIVE: Carotid intraplaque hemorrhage (IPH) is a well-known risk indicator of thromboembolism, but it is not easy to rapidly detect IPH in acute symptomatic carotid disease. The aim of this study was to assess the utility of time-of-flight (TOF) magnetic resonance angiography (MRA) in the detection of IPH and evaluate the degree of stenosis and stroke patterns in patients with acute symptomatic carotid disease. METHODS: We retrospectively identified consecutive patients with acute symptomatic carotid disease who were admitted within 12 h after stroke onset. Fifty-nine patients underwent TOF MRA at admission and were categorized according to the presence or absence of intraplaque high signal intensity (HSI). The severity of carotid stenosis and diffusion-weighted magnetic resonance imaging lesion patterns were evaluated. RESULTS: Intraplaque HSI was detected in 28.8% of the enrolled patients (17/59). Mild-to-moderate symptomatic carotid stenosis was more frequent in the intraplaque HSI-positive group (70.6%) than in the intraplaque HSI-negative group (42.8%) (p = 0.015). The patients with intraplaque HSI more frequently exhibited a disseminated small infarction pattern (76.5% in the intraplaque HSI-positive group, 47.6% in the -negative group), and did not exhibit a border-zone infarction pattern (0% in the positive group, 16.7% in the negative group). CONCLUSIONS: TOF MRA may be a useful noninvasive and rapid tool to detect IPH in patients with acute symptomatic carotid disease. IPH was common in those with a lower degree of carotid stenosis and manifested as a disseminated small infarction pattern. Intraplaque HSI on TOF MRA in acute symptomatic carotid disease may help to determine the mechanism of stroke and establish early treatment plans.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Estenose das Carótidas/diagnóstico , Hemorragia/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Medicina (B Aires) ; 80(1): 84-86, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32044745

RESUMO

Klippel-Trenaunay-Weber syndrome (KTWS) is a rare venous malformation that generally affects the lower limbs and, more infrequently, the upper limbs. It is characterized by cutaneous angiomatous formations, varicose veins and hypertrophy of the affected limb. The involvement of the genitourinary tract is extremely infrequent. We expose the case of a 14 years old female patient who was admitted for macroscopic hematuria of 48 hours of evolution and metrorrhagia with severe hemodynamic decompensation. The patient was under study for presenting a hemangioma in the lower left limb that extended to the pelvic region. Urethrocystofibroscopy showed the presence of multiple wide-spread angiomatous lesions in the bladder, some of them with active bleeding. The angio-resonance showed a voluminous hypervascular formation in contact with the bladder wall showing several arteriovenous fistulas at the pelvic level and in the left lower limb confirming the etiological diagnosis. A selective arterial embolization of the internal and external iliac territories was performed and then, a laser endocoagulation of the bleeding angiomatous foci was carried out. The hematuria completely stopped within 24 hours later of the procedure. The metrorrhagia associated with KTWS was controlled by the use of LHRH analogs and progestogens.


Assuntos
Procedimentos Endovasculares/métodos , Síndrome de Klippel-Trenaunay-Weber/cirurgia , Metrorragia/cirurgia , Adolescente , Feminino , Doenças da Vesícula Biliar/patologia , Doenças da Vesícula Biliar/cirurgia , Hemangioma/patologia , Hemangioma/cirurgia , Hematúria/patologia , Hematúria/cirurgia , Humanos , Síndrome de Klippel-Trenaunay-Weber/diagnóstico por imagem , Síndrome de Klippel-Trenaunay-Weber/patologia , Angiografia por Ressonância Magnética/métodos , Metrorragia/patologia , Pelve
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