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1.
AJNR Am J Neuroradiol ; 45(4): 386-392, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38548304

RESUMO

BACKGROUND AND PURPOSE: Carotid siphon calcification might contribute to the high prevalence of cerebrovascular disease in pseudoxanthoma elasticum through increased arterial flow pulsatility. This study aimed to compare intracranial artery flow pulsatility, brain volumes, and small-vessel disease markers between patients with pseudoxanthoma elasticum and controls and the association between arterial calcification and pulsatility in pseudoxanthoma elasticum. MATERIALS AND METHODS: Fifty patients with pseudoxanthoma elasticum and 40 age- and sex-matched controls underwent 3T MR imaging, including 2D phase-contrast acquisitions for flow pulsatility in the assessment of ICA and MCA and FLAIR acquisitions for brain volumes, white matter lesions, and infarctions. All patients with pseudoxanthoma elasticum underwent CT scanning to measure siphon calcification. Flow pulsatility (2D phase-contrast), brain volumes, white matter lesions, and infarctions (3D T1 and 3D T2 FLAIR) were compared between patients and controls. The association between siphon calcification and pulsatility in pseudoxanthoma elasticum was tested with linear regression models. RESULTS: Patients with pseudoxanthoma elasticum (mean age, 57 [SD, 12] years; 24 men) had significantly higher pulsatility indexes (1.05; range, 0.94-1.21 versus 0.94; range, 0.82-1.04; P = .02), lower mean GM volumes (597 [SD, 53] mL versus 632 [SD, 53] mL; P < .01), more white matter lesions (2.6; range, 0.5-7.5 versus 1.1; range, 0.5-2.4) mL; P = .05), and more lacunar infarctions (64 versus 8, P = .04) than controls (mean age, 58 [SD, 11] years; 20 men). Carotid siphon calcification was associated with higher pulsatility indexes in patients with pseudoxanthoma elasticum (ß = 0.10; 95% CI, 0.01-0.18). CONCLUSIONS: Patients with pseudoxanthoma elasticum have increased intracranial artery flow pulsatility and measures of small-vessel disease. Carotid siphon calcification might underlie the high prevalence of cerebrovascular disease in pseudoxanthoma elasticum.


Assuntos
Lesões Encefálicas , Calcinose , Transtornos Cerebrovasculares , Pseudoxantoma Elástico , Masculino , Humanos , Pessoa de Meia-Idade , Pseudoxantoma Elástico/complicações , Pseudoxantoma Elástico/diagnóstico por imagem , Pseudoxantoma Elástico/patologia , Artéria Carótida Interna/patologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/complicações , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Infarto
2.
J Cardiovasc Comput Tomogr ; 17(3): 192-200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37150661

RESUMO

INTRODUCTION: 5-year mortality of chronic limb-threatening ischemia (CLTI) is 50-60% and coronary artery disease (CAD) is the main cause of death of CLTI patients, followed by stroke. The aim of this study is to quantify and qualify the calcium load in different arterial territories in patients with CLTI. METHODS: Prospectively, 60 patients with CLTI were included and received a full-body CT scan. 6 patients were excluded. Different arterial territories (the peripheral lower extremity arteries, coronary arteries, extracranial and intracranial carotid arteries, thoracic and abdominal aorta) were analyzed. Analysis and interrelations of both quantitative and semi-quantitative CT measurements was performed. RESULTS: Mean age was 72 years (range 47-95; SD 11.4). Almost all CLTI patients had calcified arterial beds (femoropopliteal 100%, crural 98.1%, coronary 100%, carotid bifurcation 96.2%, internal carotid artery 98.1%, thoracic aorta 96.2%, abdominal aorta 92.3%). Nearly all arterial territories had severe calcifications. 57% had a very high coronary Agatston score (>1000), and 35% extremely high (>2000). Calcifications in the lower extremity were significantly correlated to CAC score, carotid artery bifurcation calcification score, and to a lesser extent correlated to annular calcifications in the aorta. Very high and extremely high total CAC scores were strongly correlated with severe lower extremity arterial calcifications and severe carotid and intracranial internal carotid artery, thoracic and abdominal aorta calcifications in patients with CLTI patients. CONCLUSIONS: In CLTI patients nearly all arterial territories are severely calcified, suggesting that systemic calcification plays an important role in the poor outcome of this disease.


Assuntos
Calcinose , Doenças das Artérias Carótidas , Doença Arterial Periférica , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Isquemia Crônica Crítica de Membro , Cálcio , Valor Preditivo dos Testes , Extremidade Inferior/irrigação sanguínea , Artéria Femoral , Doença Arterial Periférica/diagnóstico por imagem , Fatores de Risco , Resultado do Tratamento , Estudos Retrospectivos , Doença Crônica
3.
CVIR Endovasc ; 5(1): 26, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666322

RESUMO

BACKGROUND: Pathologic studies have shown that in patients with critical limb threatening ischaemia (CLTI) medial arterial calcifications are frequently found and may be responsible for aggravating the disease. These extensive calcifitcations are found not only in arteries of the leg but also in the coronary arteries and the aorta. The progression of these calcifications is fast and they stiffen the vessel wall and may thus increase the cardiovascular risk. Reduction of progression of calcification may not only reduce the burden of CLTI but may also reduce the high residual cardiovascular risk. Medial calcifications have been halted by etidronate in other trials. Its potential to reduce the burden from peripheral vascular disease in CLTI and residual cardiovascular risk remains to be established. METHODS: This is an investigator-initiated multicenter, double blind, placebo-controlled, randomized trial comparing the effects of etidronate versus placebo in patients with CLTI. Subjects will be randomized to either treatment with etidronate for 12 months (cyclical 20 mg/kg for 2 weeks on and 10 weeks off) orally or placebo for 12 months (in a similar routine). The primary endpoint is the change in arterial calcification as quantified by CT-scan. Secondary endpoints are the number of amputations above and below the ankle, mortality, number of vascular interventions and quality of life. DISCUSSION: Up to now, the inert end stage of vascular disease in patients with CLTI, has been considered calcification of vessel walls. We believe there is reason to reverse causation and hypothesize that calcification causes vascular disease. This reversal can be proven in a clinical trial if halting the calcification process improves the outcome of the patient. Therefore we use etidronate, a bisphosphate that has proven to stop the calcification in several rare monogenetic calcifying diseases. We aim to perform this mechanistic proof-of-concept study hopefully leading to a clinical outcome study later on.

4.
AJNR Am J Neuroradiol ; 42(11): 2030-2033, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34561212

RESUMO

We compared velocity pulsatility, distensibility, and pulsatility attenuation along the intracranial ICA and MCA between 50 patients with pseudoxanthoma elasticum and 40 controls. Patients with pseudoxanthoma elasticum had higher pulsatility and lower distensibility at all measured locations, except for a similar distensibility at C4. The pulsatility attenuation over the siphon was similar between patients with pseudoxanthoma elasticum and controls. This finding suggests that other disease mechanisms are the main contributors to increased intracranial pulsatility in pseudoxanthoma elasticum.


Assuntos
Pseudoxantoma Elástico , Artéria Carótida Interna , Humanos , Pseudoxantoma Elástico/diagnóstico por imagem
5.
Haemophilia ; 24(6): 971-979, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29790633

RESUMO

INTRODUCTION: Recurrent joint bleeding is the hallmark of haemophilia. Synovial hypertrophy observed with Magnetic Resonance Imaging (MRI) is associated with an increased risk of future joint bleeding. AIM: The aim of this study was to investigate whether point-of-care ultrasound (POC-US) is an accurate alternative for MRI for the detection of early joint changes. METHODS: In this single centre diagnostic accuracy study, bilateral knees and ankles of haemophilia patients with no or minimal arthropathy on X-rays were scanned using POC-US and 3 Tesla MRI. POC-US was performed by 1 medical doctor, blinded for MRI, according to the "Haemophilia Early Arthropathy Detection with Ultrasound" (HEAD-US) protocol. MRIs were independently scored by 2 radiologists, blinded for clinical data and ultrasound results. Diagnostic accuracy parameters were calculated with 95% confidence intervals (CI). RESULTS: Knees and ankles of 24 haemophilia patients (96 joints), aged 18-34, were studied. Synovial hypertrophy on MRI was observed in 20% of joints. POC-US for synovial tissue was correct (overall accuracy) in 97% (CI: 91-99) with a positive predictive value of 94% (CI: 73-100) and a negative predictive value of 97% (CI: 91-100). The overall accuracy of POC-US for cartilage abnormalities was 91% (CI: 83-96) and for bone surface irregularities 97% (CI: 91-99). CONCLUSION: POC-US could accurately assess synovial hypertrophy, bone surface irregularities and cartilage abnormalities in haemophilia patients with limited joint disease. As POC-US is an accurate and available alternative for MRI, it can be used for routine evaluation of early joint changes.


Assuntos
Hemartrose/diagnóstico por imagem , Articulações/diagnóstico por imagem , Imageamento por Ressonância Magnética , Sistemas Automatizados de Assistência Junto ao Leito , Adulto , Feminino , Hemartrose/patologia , Humanos , Articulações/patologia , Masculino , Sensibilidade e Especificidade , Ultrassonografia , Adulto Jovem
6.
PLoS One ; 12(9): e0183855, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28949967

RESUMO

PURPOSE: To establish a preoperative decision model for accurate indication of systemic therapy in early-stage breast cancer using multiparametric MRI at 7-tesla field strength. MATERIALS AND METHODS: Patients eligible for breast-conserving therapy were consecutively included. Patients underwent conventional diagnostic workup and one preoperative multiparametric 7-tesla breast MRI. The postoperative (gold standard) indication for systemic therapy was established from resected tumor and lymph-node tissue, based on 10-year risk-estimates of breast cancer mortality and relapse using Adjuvant! Online. Preoperative indication was estimated using similar guidelines, but from conventional diagnostic workup. Agreement was established between preoperative and postoperative indication, and MRI-characteristics used to improve agreement. MRI-characteristics included phospomonoester/phosphodiester (PME/PDE) ratio on 31-phosphorus spectroscopy (31P-MRS), apparent diffusion coefficients on diffusion-weighted imaging, and tumor size on dynamic contrast-enhanced (DCE)-MRI. A decision model was built to estimate the postoperative indication from preoperatively available data. RESULTS: We included 46 women (age: 43-74yrs) with 48 invasive carcinomas. Postoperatively, 20 patients (43%) had positive, and 26 patients (57%) negative indication for systemic therapy. Using conventional workup, positive preoperative indication agreed excellently with positive postoperative indication (N = 8/8; 100%). Negative preoperative indication was correct in only 26/38 (68%) patients. However, 31P-MRS score (p = 0.030) and tumor size (p = 0.002) were associated with the postoperative indication. The decision model shows that negative indication is correct in 21/22 (96%) patients when exempting tumors larger than 2.0cm on DCE-MRI or with PME>PDE ratios at 31P-MRS. CONCLUSIONS: Preoperatively, positive indication for systemic therapy is highly accurate. Negative indication is highly accurate (96%) for tumors sized ≤2,0cm on DCE-MRI and with PME≤PDE ratios on 31P-MRS.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Período Pré-Operatório
7.
Eur Radiol ; 27(1): 188-194, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27097788

RESUMO

OBJECTIVE: To evaluate and improve the interobserver agreement for the CT-based diagnosis of diffuse idiopathic skeletal hyperostosis (DISH). METHODS: Six hundred participants of the CT arm of a lung cancer screening trial were randomly divided into two groups. The first 300 CTs were scored by five observers for the presence of DISH based on the original Resnick criteria for radiographs. After analysis of the data a consensus meeting was organised and the criteria were slightly modified regarding the definition of 'contiguous', the definition of 'flowing ossifications' and the viewing plane and window level. Subsequently, the second set of 300 CTs was scored by the same observers. κ ≥ 0.61 was considered good agreement. RESULTS: The 600 male participants were on average 63.5 (SD 5.3) years old and had smoked on average 38.0 pack-years. In the first round κ values ranged from 0.32 to 0.74 and 7 out of 10 values were below 0.61. After the consensus meeting the interobserver agreement ranged from 0.51 to 0.86 and 3 out of 10 values were below 0.61. The agreement improved significantly. CONCLUSIONS: This is the first study that reports interobserver agreement for the diagnosis of DISH on chest CT, showing mostly good agreement for modified Resnick criteria. KEY POINTS: • DISH is diagnosed on fluoroscopic and radiographic examinations using Resnick criteria • Evaluation of DISH on chest CT was modestly reproducible with the Resnick criteria • A consensus meeting and Resnick criteria modification improved inter-rater reliability for DISH • Reproducible CT criteria for DISH aids research into this poorly understood entity.


Assuntos
Hiperostose Esquelética Difusa Idiopática/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Idoso , Competência Clínica , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiografia Torácica/métodos , Radiografia Torácica/normas , Distribuição Aleatória , Reprodutibilidade dos Testes , Fumar , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
8.
EJNMMI Res ; 5(1): 76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26695768

RESUMO

PURPOSE: The purpose of this study is to give an overview of studies investigating the role of fludeoxyglucose F18 ((18)F-FDG) positron emission tomography (PET) scanning in patients with aortic aneurysms with a focus on molecular characteristics of the aneurysm wall. METHODS: MEDLINE, EMBASE, and the Cochrane database were searched for relevant articles. After inclusion and exclusion, we selected 18 relevant articles reporting on (18)F-FDG PET scanning of aortic aneurysms. RESULTS: The sample size of studies is limited, and there are no standardized imaging protocols and quantification methods. (18)F-FDG PET scanning was shown to display molecular characteristics of the aortic wall. Different studies showed contradictory findings of aortic (18)F-FDG uptake in aneurysm patients compared to controls. CONCLUSIONS: Non-invasively determining molecular characteristics of aortic wall weakening might lead to better rupture and growth prediction. This might influence the decision of the surgeon between conservative and surgical treatment of aneurysms. To date, there is conflicted evidence regarding the use of (18)F-FDG PET scanning to predict aneurysm rupture and growth. The role of (18)F-FDG PET scanning in rupture risk prediction needs to be further investigated, and standardized imaging protocols and quantification methods need to be implemented.

9.
Phys Med Biol ; 60(14): 5527-42, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26133986

RESUMO

MR-guided HIFU ablation is a promising technique for the non-invasive treatment of breast cancer. A phase I study was performed to assess the safety and treatment accuracy and precision of MR-HIFU ablation in breast cancer patients (n=10) using a newly developed MR-HIFU platform dedicated to applications in the breast. In this paper a technical analysis of the performance of the dedicated breast MR-HIFU system during breast tumors ablation is described. The main points of investigation were the spatial targeting accuracy and precision of the system and the performance of real-time respiration-corrected MR thermometry.The mean targeting accuracy was in the range of 2.4-2.6 mm, whereas the mean targeting precision was in the range of 1.5-1.8 mm. To correct for respiration-induced magnetic field fluctuations during MR temperature mapping a look-up-table (LUT)-based correction method was used. An optimized procedural sedation protocol in combination with the LUT-based correction method allowed for precise MR thermometry during the ablation procedure (temperature standard deviation <3 °C). No unwanted heating in the near field (i.e. skin) nor in the far field (pectoral muscle) was detected.The newly developed dedicated breast MR-HIFU system allows for safe, accurate and precise ablation of breast tumors.


Assuntos
Neoplasias da Mama/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Termometria/métodos , Mama/citologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Meios de Contraste/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Invasividade Neoplásica , Temperatura
10.
Neth Heart J ; 23(6): 312-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25920514
11.
AJNR Am J Neuroradiol ; 36(6): 1056-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25907522

RESUMO

BACKGROUND AND PURPOSE: Ischemic stroke studies emphasize a difference between reperfusion and recanalization, but predictors of reperfusion have not been elucidated. The aim of this study was to evaluate the relationship between reperfusion and recanalization and identify predictors of reperfusion. MATERIALS AND METHODS: From the Dutch Acute Stroke Study, 178 patients were selected with an MCA territory deficit on admission CTP and day 3 follow-up CTP and CTA. Reperfusion was evaluated on CTP, and recanalization on CTA, follow-up imaging. Reperfusion percentages were calculated in patients with and without recanalization. Patient admission and treatment characteristics and admission CT imaging parameters were collected. Their association with complete reperfusion was analyzed by using univariate and multivariate logistic regression. RESULTS: Sixty percent of patients with complete recanalization showed complete reperfusion (relative risk, 2.60; 95% CI, 1.63-4.13). Approximately one-third of patients showed some discrepancy between recanalization and reperfusion status. Lower NIHSS score (OR, 1.06; 95% CI, 1.01-1.11), smaller infarct core size (OR, 3.11; 95% CI, 1.46-6.66; and OR, 2.40; 95% CI, 1.14-5.02), smaller total ischemic area (OR, 4.20; 95% CI, 1.91-9.22; and OR, 2.35; 95% CI, 1.12-4.91), lower clot burden (OR, 1.35; 95% CI, 1.14-1.58), distal thrombus location (OR, 3.02; 95% CI, 1.76-5.20), and good collateral score (OR, 2.84; 95% CI, 1.34-6.02) significantly increased the odds of complete reperfusion. In multivariate analysis, only total ischemic area (OR, 6.12; 95% CI, 2.69-13.93; and OR, 1.91; 95% CI, 0.91-4.02) was an independent predictor of complete reperfusion. CONCLUSIONS: Recanalization and reperfusion are strongly associated but not always equivalent in ischemic stroke. A smaller total ischemic area is the only independent predictor of complete reperfusion.


Assuntos
Neovascularização Fisiológica/fisiologia , Traumatismo por Reperfusão/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Isquemia Encefálica/diagnóstico por imagem , Angiografia Cerebral/métodos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
12.
Neth Heart J ; 23(2): 133-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25410576

RESUMO

BACKGROUND: More than 90 % of exercise-related cardiac arrests occur in men, predominantly those aged 45 years and older with coronary artery disease (CAD) as the main cause. The current sports medical evaluation (SME) of middle-aged recreational athletes consists of a medical history, physical examination, and resting and exercise electrocardiography. Coronary CT (CCT) provides a minimally invasive low radiation dose opportunity to image the coronary arteries. We present the study protocol of the Measuring Athlete's Risk of Cardiovascular events (MARC) study. MARC aims to assess the additional value of CCT to a routine SME in asymptomatic sportsmen ≥45 years without known CAD. DESIGN: MARC is a prospective study of 300 asymptomatic sportsmen ≥45 years who will undergo CCT if the SME does not reveal any cardiac abnormalities. The prevalence and determinants of CAD (coronary artery calcium score ≥100 Agatston Units (AU) or ≥50 % luminal stenosis) will be reported. The number needed to screen to prevent the occurrence of one cardiovascular event in the next 5 years, conditional to adequate treatment, will be estimated. DISCUSSION: We aim to determine the prevalence and severity of CAD and the additional value of CCT in asymptomatic middle-aged (≥45 years) sportsmen whose routine SME revealed no cardiac abnormalities.

13.
Eur Radiol ; 25(1): 132-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25323601

RESUMO

OBJECTIVES: Further survival benefits may be gained from low-dose chest computed tomography (CT) by assessing vertebral fractures and bone density. We sought to assess the association between CT-measured vertebral fractures and bone density with all-cause mortality in lung cancer screening participants. METHODS: Following a case-cohort design, lung cancer screening trial participants (N = 3,673) who died (N = 196) during a median follow-up of 6 years (inter-quartile range: 5.7-6.3) were identified and added to a random sample of N = 383 from the trial. We assessed vertebral fractures using Genant's semiquantative method on sagittal reconstructions and measured bone density (Hounsfield Units (HU)) in vertebrae. Cox proportional hazards modelling was used to determine if vertebral fractures or bone density were independently predictive of mortality. RESULTS: The prevalence of vertebral fractures was 35% (95% confidence interval 30-40%) among survivors and 51% (44-58%) amongst cases. After adjusting for age, gender, smoking status, pack years smoked, coronary and aortic calcium volume and pulmonary emphysema, the adjusted hazard ratio (HR) for vertebral fracture was 2.04 (1.43-2.92). For each 10 HU decline in trabecular bone density, the adjusted HR was 1.08 (1.02-1.15). CONCLUSIONS: Vertebral fractures and bone density are independently associated with all-cause mortality. KEY POINTS: • Lung cancer screening chest computed tomography contains additional, potentially useful information. • Vertebral fractures and bone density are independently predictive of mortality. • This finding has implications for screening and management decisions.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Absorciometria de Fóton , Idoso , Biomarcadores/sangue , Densidade Óssea/fisiologia , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Osteoporose/mortalidade , Fraturas por Osteoporose/mortalidade , Modelos de Riscos Proporcionais , Fumar/mortalidade , Tomografia Computadorizada por Raios X/efeitos adversos
14.
Cerebrovasc Dis ; 37(2): 116-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24435107

RESUMO

BACKGROUND: In stroke erythrocyte-rich thrombi are more sensitive to intravenous thrombolysis with recombinant tissue plasminogen activator (IV-rtPA) and have higher density on non-contrast CT (NCCT). We investigated the relationship between thrombus density and recanalization and whether persistent occlusions can be predicted by Hounsfield unit (HU) measurements. METHODS: In 88 IV-rtPA-treated patients with intracranial ICA or MCA occluding thrombus and follow-up imaging, thrombus and contralateral vessel attenuation measurements were performed on thin-slice NCCT. Mean absolute and relative HU were compared between patients with persistent occlusion (modified Thrombolysis in Cerebral Infarction system, grade 0/1/2a) and recanalization (grade 2b/3). Univariate and multivariate (adjusted for stroke subtype, clot burden score, occlusion site and time to thrombolysis) odds ratios for persistent occlusion were calculated. Additional prognostic value for persistent occlusion was estimated by adding HU measurements to the area under the curve (AUC) of known determinants and calculating optimal cut-off values. RESULTS: Patients with persistent occlusion (n = 19) had significant lower mean HU (absolute 52.2 ± 9.5, relative 1.29 ± 0.20) compared to recanalization (absolute 63.1 ± 10.7, relative 1.54 ± 0.23, both p < 0.0001). Odds ratios for persistent occlusion were 3.1 (95% confidence interval, CI 1.6-6.0) univariate and 3.1 (95% CI 1.7-5.7) multivariate per 10 absolute HU decrease and 3.2 (95% CI 1.6-6.5) univariate and 4.1 (95% CI 1.8-9.1) multivariate per 0.20 relative HU decrease. Attenuation measurements significantly increased the AUC (0.67) of the known determinants to 0.84 (absolute HU) and 0.86 (relative HU). Cut-off values of <56.5 absolute HU and <1.38 relative HU showed optimal predictive values for persistent occlusion. CONCLUSIONS: Thrombus density is related to recanalization rate. Lower absolute and relative HU are independently related to persistent occlusion and HU measurements significantly increase discriminative performances of known recanalization determinants.


Assuntos
Trombose Intracraniana/tratamento farmacológico , Terapia Trombolítica , Trombose/diagnóstico por imagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
15.
Eur Radiol ; 24(3): 603-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24078055

RESUMO

OBJECTIVE: To investigate the diagnostic value of 3-Tesla (T) breast MRI in patients presenting with microcalcifications on mammography. METHODS: Between January 2006 and May 2009, 123 patients with mammographically detected BI-RADS 3­5 microcalcifications underwent 3-T breast MRI before undergoing breast biopsy. All MRIs of the histopathologically confirmed index lesions were reviewed by two breast radiologists. The detection rate of invasive carcinoma and ductal carcinoma in situ (DCIS) was evaluated, as well as the added diagnostic value of MRI over mammography and breast ultrasound. RESULTS: At pathology, 40/123 (33%) lesions proved malignant; 28 (70%) DCIS and 12 (30%) invasive carcinoma. Both observers detected all invasive malignancies at MRI, as well as 79% (observer 1) and 86% (observer 2) of in situ lesions. MRI in addition to conventional imaging led to a significant increase in area under the receiver operating characteristic (ROC) curve from 0.67 (95% CI 0.56­0.79) to 0.79 (95% CI 0.70­0.88, observer 1) and to 0.80 (95% CI 0.71­0.89, observer 2), respectively. CONCLUSIONS: 3-T breast MRI was shown to add significant value to conventional imaging in patients presenting with suspicious microcalcifications on mammography. KEY POINTS: • 3-T MRI is increasingly used for breast imaging in clinical practice. • On 3-T breast MRI up to 86% of DCIS lesions are detected. • 3-T MRI increases the diagnostic value in patients with mammographically detected microcalcifications.


Assuntos
Neoplasias da Mama/patologia , Calcinose/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Biópsia por Agulha , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Feminino , Fibroadenoma/diagnóstico por imagem , Fibroadenoma/patologia , Doença da Mama Fibrocística/diagnóstico por imagem , Doença da Mama Fibrocística/patologia , Humanos , Mamografia , Pessoa de Meia-Idade , Invasividade Neoplásica , Curva ROC , Ultrassonografia Mamária
16.
Stroke ; 45(2): 527-32, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24347422

RESUMO

BACKGROUND AND PURPOSE: Randomized clinical trials show higher 30-day risk of stroke or death after carotid artery stenting compared with surgery. We examined whether operator experience is associated with 30-day risk of stroke or death in the Carotid Stenting Trialists' Collaboration database. METHODS: The Carotid Stenting Trialists' Collaboration is a pooled individual patient database including all patients recruited in 3 randomized trials of stenting versus endarterectomy for symptomatic carotid stenosis (Endarterectomy Versus Angioplasty in patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Angioplasty versus Carotid Endarterectomy trial, and International Carotid Stenting Study). Lifetime carotid artery stenting experience, lifetime experience in stenting procedures excluding the carotid, and annual number of procedures performed within the trial (in-trial volume), divided into tertiles, were used to measure operator experience. The outcome event was the occurrence of any stroke or death within 30 days of the procedure. The analysis was done per protocol. RESULTS: Among 1546 patients who underwent carotid artery stenting, 120 (7.8%) had a stroke or death within 30 days of the procedure. The 30-day risk of stroke or death did not differ according to operator lifetime carotid artery stenting experience (P=0.8) or operator lifetime stenting experience excluding the carotid (P=0.7). In contrast, the 30-day risk of stroke or death was significantly higher in patients treated by operators with low (mean ≤3.2 procedures/y; risk 10.1%; adjusted risk ratio=2.30 [1.36-3.87]) and intermediate annual in-trial volumes (3.2-5.6 procedures/y; 8.4%; adjusted risk ratio=1.93 [1.14-3.27]) compared with patients treated by high annual in-trial volume operators (>5.6 procedures/y; 5.1%). CONCLUSIONS: Carotid stenting should only be performed by operators with annual procedure volume ≥6 cases per year.


Assuntos
Estenose das Carótidas/cirurgia , Stents , Idoso , Idoso de 80 Anos ou mais , Angioplastia , Estenose das Carótidas/complicações , Estenose das Carótidas/mortalidade , Protocolos Clínicos , Bases de Dados Factuais , Endarterectomia das Carótidas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento
17.
Eur J Vasc Endovasc Surg ; 46(4): 411-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954165

RESUMO

OBJECTIVE: To study the changes in peak systolic velocities of the ipsilateral external carotid artery (ECA) following carotid revascularization. METHODS: All patients randomized to carotid artery stenting (CAS) or carotid endarterectomy (CEA) in the International Carotid Stenting Study (ICSS; ISRCTN25337470) in our center were included. Peak systolic velocities (PSV) were assessed with duplex ultrasound (DUS) at baseline, at 30 days, and at 12 and 24 months after treatment. Our primary outcome measure was the change in blood flow velocities in the ECA (ΔPSVECA). Secondary outcome measure was the prevalence of post interventional ECA occlusion. RESULTS: Of 270 patients enrolled in ICSS at our center, 224 patients (mean age, 68.8 years; 154 males) were included in the present study (116 CAS, 108 CEA). Baseline PSV in the ipsilateral ECA was similar between the groups. Following CAS, PSV gradually increased during follow-up, whereas PSV remained relatively stable after CEA; mean difference of PSV between CAS and CEA: 23 cm/s (95% CI, -5 to 52), 58 cm/s (95% CI, 27-89), and 69 cm/s (95% CI, 31-107) at 30 days, 12 months, and 24 months. One new ECA occlusion occurred after CAS and two after CEA. CONCLUSION: Blood flow velocities in the ipsilateral ECA increase significantly after CAS but not after CEA. However, this does not lead to a higher rate of ECA occlusion in the first 2 years after revascularization. We conclude that CAS is not inferior to CEA in preserving the ECA as a possible potential collateral pathway for cerebral blood supply within 2 years following revascularization.


Assuntos
Angioplastia , Artéria Carótida Externa/cirurgia , Estenose das Carótidas/terapia , Endarterectomia das Carótidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Amaurose Fugaz/etiologia , Amaurose Fugaz/fisiopatologia , Angioplastia/instrumentação , Velocidade do Fluxo Sanguíneo , Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Externa/fisiopatologia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/cirurgia , Circulação Cerebrovascular , Circulação Colateral , Feminino , Humanos , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/fisiopatologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Recidiva , Fluxo Sanguíneo Regional , Índice de Gravidade de Doença , Stents , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler Dupla
18.
Eur Radiol ; 23(11): 2961-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23982289

RESUMO

OBJECTIVE: To assess the feasibility of 7-T contrast-enhanced breast MRI in patients with suspicious masses. METHODS: Twenty patients with 23 suspicious breast masses on conventional imaging (mean size 13 mm, range 5-27 mm) were examined at 7 T. The MRI protocol included a dynamic series with injection of 0.1 mmol/kg gadobutrol (seven consecutive 3D T1-weighted gradient echo sequences, resolution 1 × 1 × 2 mm(3), temporal resolution 63 s) and ultra-high-resolution imaging (T1-weighted 3D gradient echo sequence, resolution 0.45 × 0.57 × 0.45 mm(3)). Two observers (R1 and R2) independently judged the examinations on image quality and classified lesions according to BI-RADS. The added value of ultra-high-resolution imaging was assessed. RESULTS: The image quality was deemed excellent in 1 and 0, good in 10 and 12, sufficient in 8 and 8, and insufficient in 1 and 0 for R1 and R2 respectively. Twenty of the 23 lesions were identified at 7-T MRI by both observers. All histopathologically proven malignant lesions (n = 19) were identified and classified as BI-RADS-MRI 4 or 5. Ultra-high-resolution imaging increased reader confidence in 88 % (R1) and 59 % (R2) of acquisitions. CONCLUSION: The study shows the feasibility of dynamic contrast-enhanced 7-T breast MRI, where all malignant mass lesions were identified by two observers. KEY POINTS: • Magnetic resonance imaging is important in the evaluation of breast cancer. • Recently, 7-T MRI has become available. • The 7-T dynamic contrast-enhanced breast MRI is feasible in patients. • The 7-T breast examinations are amenable to evaluation according to BI-RADS.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/patologia , Meios de Contraste , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos , Adulto , Idoso , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
19.
Neuroradiology ; 55(9): 1071-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23793862

RESUMO

INTRODUCTION: More insights in the etiopathogenesis of thrombi could be helpful in the treatment of patients with acute ischemic stroke. The aim of our study was to determine the relationship between presence of a hyperdense vessel sign and thrombus density with different stroke subtypes. METHODS: We included 123 patients with acute ischemic anterior circulation stroke and a visible occlusion on CT-angiography caused by cardioembolism (n = 53), large artery atherosclerosis (n = 55), or dissection (n = 15). Presence or absence of a hyperdense vessel sign was assessed and thrombus density was measured in Hounsfield Units (HU) on non-contrast 1 mm thin slices CT. Subsequently, occurrence of hyperdense vessel sign and thrombus density (absolute HU and rHU (=HU thrombus/HU contralateral)) were related with stroke subtypes. RESULTS: The presence of hyperdense vessel signs differed significantly among subtypes and was found in 45, 64 and 93 % of patients with cardioembolism, large artery atherosclerosis and dissection, respectively (p = 0.003). The mean HU and rHU (+95 % CI) of the thrombi in all vessels were respectively 56.1 (53.2-59.0) and 1.39 (1.33-1.45) in cardioembolism, 64.6 (62.2-66.9) and 1.59 (1.54-1.64) in large artery atherosclerosis and 76.4 (73.0-79.8) and 1.88 (1.79-1.97) in dissection (p < 0.0001). We found the same significant ranking order in the density of thrombi with hyperdense vessel signs (mean HU and rHU (+95 % CI), respectively): cardioembolism 61.3 (57.4-65.3) and 1.49 (57.4-65.3); large artery atherosclerosis 67.3 (64.9-69.7) and 1.65 (1.58-1.71); dissection 76.4 (72.6-80.1) and 1.89 (1.79-1.99, p < 0.0001). CONCLUSION: Presence of a hyperdense vessel sign and thrombus density are related to stroke subtype.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Angiografia Cerebral/estatística & dados numéricos , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/epidemiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Idoso , Causalidade , Estudos de Coortes , Comorbidade , Diagnóstico Diferencial , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/estatística & dados numéricos
20.
Haemophilia ; 19(6): 939-43, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23710616

RESUMO

Magnetic resonance imaging (MRI) is the most sensitive imaging modality to assess joint lesions, but the clinical relevance of subtle joint changes in haemophilic patients playing sports is unknown. A haemophilia specific MRI score is available, but was never evaluated in physically active healthy controls. It is not known if unexpected MRI changes in young active haemophilic patients are due to sports participation. The aim of this study was to evaluate knees and ankles in a cohort of young active healthy men using a haemophilia specific MRI score to provide context for joint evaluation by MRI in young haemophilic patients. Three Tesla MRI of knees and ankles were performed in 30 healthy men aged 18-26 years, regularly active in sports. MR images were scored by a single independent radiologist, using the International Prophylaxis Study Group additive MRI score. One physiotherapist assessed clinical function using the Haemophilia joint health scores (HJHS). History of complaints or injuries affecting knees and/or ankles, very intensive sports and current sports activities were documented. Median age was 24.3 years (range 19.0-26.4) and median number of sports activities per week was 3 (range 1-4). Six joints (five knees, one ankle) had a history of a sports-related injury. The median HJHS per joint was 0 out of 20 (range 0-1). All joints had a MRI score of 0. These results suggest that regular sports participation or very low HJHS scores are not associated with haemophilia specific MRI changes in knees and ankles.


Assuntos
Tornozelo/diagnóstico por imagem , Transtornos Herdados da Coagulação Sanguínea/fisiopatologia , Articulação do Joelho/diagnóstico por imagem , Índice de Gravidade de Doença , Adulto , Tornozelo/fisiopatologia , Humanos , Articulação do Joelho/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Radiografia , Esportes , Adulto Jovem
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