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1.
Eur Radiol ; 26(3): 639-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26105021

RESUMO

OBJECTIVES: This study aimed to evaluate the prevalence of colonic diverticula according to age, gender, distribution, disease extension and symptoms with CT colonography (CTC). METHODS: The study population included 1091 consecutive patients who underwent CTC. Patients with diverticula were retrospectively stratified according to age, gender, clinical symptoms and colonic segment involvement. Extension of colonic diverticula was evaluated using a three-point quantitative scale. Using this data, a multivariate regression analysis was applied to investigate the existence of any correlation among variables. RESULTS: Colonic diverticula were observed in 561 patients (240 men, mean age 68 ± 12 years). Symptomatic uncomplicated diverticular disease (SUDD) was present in 47.4% of cases. In 25.6% of patients ≤40 years, at least one diverticulum in the colon was observed. Prevalence of right-sided diverticula in patients >60 years was 14.2% in caecum and 18.5% in ascending colon. No significant difference was found between symptomatic and asymptomatic patients regarding diverticula prevalence and extension. No correlation was present between diverticula extension and symptoms. CONCLUSION: The incidence of colonic diverticula appears to be greater than expected. Right colon diverticula do not appear to be an uncommon finding, with their prevalence increasing with patient age. SUDD does not seem to be related to diverticula distribution and extension. KEY POINTS: Incidence of colonic diverticula appears to be greater than expected. Right colon diverticula do not appear to be an uncommon finding. SUDD does not seem to be related to diverticula distribution and extension.


Assuntos
Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Divertículo do Colo/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Doenças do Ceco/diagnóstico por imagem , Doenças do Ceco/epidemiologia , Colo Ascendente/diagnóstico por imagem , Colo Descendente/diagnóstico por imagem , Colo Sigmoide/diagnóstico por imagem , Colo Transverso/diagnóstico por imagem , Meios de Contraste , Divertículo do Colo/diagnóstico por imagem , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/estatística & dados numéricos , Prevalência , Estudos Retrospectivos , Fatores Sexuais
2.
Circulation ; 130(6): 484-95, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25092278

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden death in the young, although not all patients eligible for sudden death prevention with an implantable cardioverter-defibrillator are identified. Contrast-enhanced cardiovascular magnetic resonance with late gadolinium enhancement (LGE) has emerged as an in vivo marker of myocardial fibrosis, although its role in stratifying sudden death risk in subgroups of HCM patients remains incompletely understood. METHODS AND RESULTS: We assessed the relation between LGE and cardiovascular outcomes in 1293 HCM patients referred for cardiovascular magnetic resonance and followed up for a median of 3.3 years. Sudden cardiac death (SCD) events (including appropriate defibrillator interventions) occurred in 37 patients (3%). A continuous relationship was evident between LGE by percent left ventricular mass and SCD event risk in HCM patients (P=0.001). Extent of LGE was associated with an increased risk of SCD events (adjusted hazard ratio, 1.46/10% increase in LGE; P=0.002), even after adjustment for other relevant disease variables. LGE of ≥15% of LV mass demonstrated a 2-fold increase in SCD event risk in those patients otherwise considered to be at lower risk, with an estimated likelihood for SCD events of 6% at 5 years. Performance of the SCD event risk model was enhanced by LGE (net reclassification index, 12.9%; 95% confidence interval, 0.3-38.3). Absence of LGE was associated with lower risk for SCD events (adjusted hazard ratio, 0.39; P=0.02). Extent of LGE also predicted the development of end-stage HCM with systolic dysfunction (adjusted hazard ratio, 1.80/10% increase in LGE; P<0.03). CONCLUSIONS: Extensive LGE measured by quantitative contrast enhanced CMR provides additional information for assessing SCD event risk among HCM patients, particularly patients otherwise judged to be at low risk.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/mortalidade , Meios de Contraste , Morte Súbita Cardíaca/epidemiologia , Gadolínio , Imagem Cinética por Ressonância Magnética/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Método Simples-Cego , Adulto Jovem
3.
Radiology ; 276(3): 706-14, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25786157

RESUMO

PURPOSE: To use suitable objective methods of analysis to assess the influence of the combination of an integrated-circuit computed tomographic (CT) detector and iterative reconstruction (IR) algorithms on the visualization of small (≤3-mm) coronary artery stents. MATERIALS AND METHODS: By using a moving heart phantom, 18 data sets obtained from three coronary artery stents with small diameters were investigated. A second-generation dual-source CT system equipped with an integrated-circuit detector was used. Images were reconstructed with filtered back-projection (FBP) and IR at a section thickness of 0.75 mm (FBP75 and IR75, respectively) and IR at a section thickness of 0.50 mm (IR50). Multirow intensity profiles in Hounsfield units were modeled by using a sum-of-Gaussians fit to analyze in-plane image characteristics. Out-of-plane image characteristics were analyzed with z upslope of multicolumn intensity profiles in Hounsfield units. Statistical analysis was conducted with one-way analysis of variance and the Student t test. RESULTS: Independent of stent diameter and heart rate, IR75 resulted in significantly increased xy sharpness, signal-to-noise ratio, and contrast-to-noise ratio, as well as decreased blurring and noise compared with FBP75 (eg, 2.25-mm stent, 0 beats per minute; xy sharpness, 278.2 vs 252.3; signal-to-noise ratio, 46.6 vs 33.5; contrast-to-noise ratio, 26.0 vs 16.8; blurring, 1.4 vs 1.5; noise, 15.4 vs 21.2; all P < .001). In the z direction, the upslopes were substantially higher in the IR50 reconstructions (2.25-mm stent: IR50, 94.0; IR75, 53.1; and FBP75, 48.1; P < .001). CONCLUSION: The implementation of an integrated-circuit CT detector provides substantially sharper out-of-plane resolution of coronary artery stents at 0.5-mm section thickness, while the use of iterative image reconstruction mostly improves in-plane stent visualization.


Assuntos
Vasos Coronários , Processamento de Imagem Assistida por Computador , Stents , Tomografia Computadorizada por Raios X , Algoritmos , Imagens de Fantasmas , Desenho de Prótese
4.
Cardiology ; 131(2): 122-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25925893

RESUMO

OBJECTIVES: An increased dispersion of myocardial repolarization represents one of the mechanisms underlying the arrhythmic risk in hypertrophic cardiomyopathy (HCM). We investigated spatial myocardial repolarization dispersion indices in HCM patients with nonsustained ventricular tachycardia (NSVT) and, contextually, their main clinical determinants. METHODS: Fifty-two well-matched HCM outpatients were categorized into two groups according to the presence or the absence of NSVT at 24-hour Holter electrocardiogram (ECG) monitoring. Each patient underwent a clinical examination, including Doppler echocardiogram integrated with tissue Doppler imaging, cardiac magnetic resonance, and 12-lead surface ECG to calculate the dispersion for the following intervals: QRS, Q-Tend (QTe), Q-Tpeak, Tpeak-Tend (TpTe), J-Tpeak, and J-Tend. RESULTS: The NSVT group showed only QTe dispersion and TpTe dispersion values to be significantly higher than their counterparts. NSVT occurrence was independently predicted by late gadolinium enhancement presence (p=0.021) and QTe Bazett dispersion (p=0.030), the latter strongly associated with the myocardial performance index (MPI) obtained at the basal segment of the interventricular septum (p=0.0004). CONCLUSION: Our data support QTe dispersion as an easy and noninvasive tool for identifying HCM patients with NSVT propensity. The strong relationship between QTe dispersion and MPI allows us to hypothesize an intriguing link between electrical instability and confined myocardial areas of systodiastolic dysfunction.


Assuntos
Cardiomiopatia Hipertrófica/complicações , Sistema de Condução Cardíaco/fisiologia , Taquicardia Ventricular/diagnóstico , Cardiomiopatia Hipertrófica/fisiopatologia , Diástole/fisiologia , Ecocardiografia Doppler , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole/fisiologia , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/fisiopatologia
5.
Acta Radiol ; 56(3): 355-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24676084

RESUMO

Several imaging options are available today to diagnose endometriosis. Currently, the two techniques most used are sonography and magnetic resonance imaging (MRI). Three-dimensional (3D) sonography has proved to be particularly sensitive in the diagnosis of endometriosis. In recent years, MRI has emerged as a high reproducible method to explore endometriosis; moreover, its capability to evaluate tissue signal is an extremely powerful system in the differential diagnosis with other pathologies and for the identification of malignant degeneration. The purpose of this paper is to present the state-of-the-art of MRI of endometriosis by performing a review of the literature and showing the epidemiology, pathogenesis, and classification of endometriosis. In this work, the technique that should be used, MR findings of endometriosis and the principles of differential diagnosis are explained.


Assuntos
Endometriose/diagnóstico , Imageamento por Ressonância Magnética/métodos , Diagnóstico Diferencial , Feminino , Humanos , Ovário/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sistema Urinário/patologia
6.
Acta Radiol ; 56(4): 413-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24615417

RESUMO

BACKGROUND: Monoenergetic extrapolation of cardiac dual-energy computed tomography (DECT) could be useful in artifact reduction in clinical practice. PURPOSE: To evaluate the potential of monoenergetic extrapolation of cardiac DECT data for reducing artifacts from metal and high iodine contrast concentration. MATERIAL AND METHODS: With IRB approval and in HIPAA compliance, 35 patients (22 men, 61 ± 12 years) underwent cardiac DECT with dual-source CT (100 kVp and 140 kVp). Contrast material injection protocols were adapted to the patient's weight using non-ionic low-osmolar 370 mgI/mL iopromide. Datasets were transferred to a stand-alone workstation and dedicated monoenergetic analysis software was used for postprocessing. Reconstructions with the following five photon energies were generated: 40 keV, 60 keV, 80 keV, 100 keV, and 120 keV. Artifact severity was graded on a 5-point Likert scale (0, massive artifact; 5, absence of artifact). The size of artifact and image noise (expressed as HU) in anatomic structures adjacent to the artifact were measured. Quantitative and subjective image quality was compared using Friedman and Wilcoxon tests. RESULTS: We observed artifacts arising from densely concentrated contrast material in the superior vena cava (SVC) in 18 patients, from sternal wires in 14, from bypass clips in eight, and from coronary artery stents in seven. Artifact size in monoenergetic reconstructions from 40 to 120 keV decreased from 21.3 to 19 mm for the SVC (P < 0.001), from 8.4 to 2.6 mm for sternal wires (P < 0.001), from 6.4 to 2.2 mm for bypass clips (P < 0.001), and from 5.9 to 2.7 mm for stents (P < 0.001), respectively. The quality score changed from 0.2 to 3.8 for the SVC (P < 0.001), from 0.1 to 4 for sternal wires (P < 0.001), from 0 to 3.9 for bypass clips (P < 0.001), and from 0 to 3.9 for stents (P < 0.001). Lowest noise in adjacent structures was found at 80 keV for the SVC (39.1 HU), for sternal wires (33.3), for bypass clips (26.9), and for stents (33.9). CONCLUSION: A significant reduction of high-attenuation artifacts can be achieved by use of higher monoenergetic energy levels with cardiac DECT. However, image noise in anatomic structures affected by artifacts is lowest at 80 keV, which suggests an evaluation approach that makes use of multiple energy levels for a complete diagnosis.


Assuntos
Artefatos , Doença da Artéria Coronariana/diagnóstico por imagem , Coração/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos
7.
J Stroke Cerebrovasc Dis ; 24(2): 284-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25440349

RESUMO

PURPOSE: Cerebral microbleeds (CMBs) are small dot-like lesions appearing as hyposignals on gradient echo (GRE) T2* magnetic resonance (MR) sequences, whereas the leukoaraiosis (LA) indicates the presence of patchy areas of hypersignal on fluid-attenuated inversion recovery (FLAIR) MR sequences in the periventricular white matter. The purpose of this work was to evaluate the association between LA and CMBs. MATERIAL AND METHODS: Eighty-five consecutive (men 55; median age 64 years) patients were retrospectively analyzed using a 1.5 T system; CMBs were studied using a T2*-weighted GRE sequence and classified as absent (grade 1), mild (grade 2; total number of microbleeds, 1-2), moderate (grade 3; total number of microbleeds, 3-10), and severe (grade 4; total number of microbleeds, >10). LA was assessed with FLAIR MR sequences and was graded based on the European Task Force on Age-Related White Matter Changes as follows: 1 (no lesions), 2 (focal lesions > 5 mm), 3 (early confluent lesions), and 4 (diffuse involvement of an entire brain region). RESULTS: We considered 170 cerebral hemispheres. The prevalence of CMBs was 24.7% (42 of 170), whereas the prevalence of LA was 27.1% (46 of 170). A statistically significant correlation was observed between LA and CMBs (correlation rho = .495, P value = .001). Multiple logistic regression analysis showed an association between CMBs and cerebrovascular symptoms (P = .0023). CONCLUSION: Results of this study suggest an association between CMBs and LA. Moreover, we found that LA is associated with the presence of cerebrovascular symptoms.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/epidemiologia , Leucoaraiose/epidemiologia , Idoso , Hemorragia Cerebral/patologia , Comorbidade , Feminino , Humanos , Leucoaraiose/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
8.
Eur Radiol ; 24(7): 1487-96, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24816935

RESUMO

PURPOSE: The primary aim was to assess the perforation rate of CTC; the secondary aim was to identify potential clinical/technical predictors of this complication. METHODS: Methods for analysis were based on PRISMA (preferred reporting items for systematic reviews and meta-analyses). From the selected studies, the rate of CTC perforation and patient/technical characteristics potentially associated with this event were extracted. Forest plots showing individual and pooled estimates of the perforation rate were obtained for all analyses. I(2) was used to evaluate heterogeneity between studies. RESULTS: Eleven articles out of the 187 initially identified were selected for the analysis (103,399 patients). There were 29,048 (28%) asymptomatic individuals and 30,773 (30%) symptomatic patients; this characteristic was not reported in the remaining subjects (42%). Colon distension was obtained manually in 69,222 (67%) and using an automated carbon dioxide insufflator in 26,479 (26%) patients; in the remaining 7% of patients, this information was missing. Twenty-eight colonic perforations were reported, with the CTC perforation rate estimated to be 0.04% (95% CI. 0.00-0.10), 19-fold higher in symptomatic than in screening subjects (OR: 19.2, CI 3.3-108 and P = 0.001). The surgical rate was 0.008%. No CTC-related deaths were reported. CONCLUSIONS: The perforation rate in CTC is very low, particularly considering asymptomatic individuals. KEY POINTS: • This is the first meta-analysis on this topic, based on 100,000 patients. • The CTC-related colorectal perforation rate is 0.04%, 0.02% in asymptomatic subjects. • The CTC-induced surgery rate is 0.008% (1:12,500). • The perforation rate in CTC is low, particularly in average-risk, asymptomatic individuals.


Assuntos
Colo/lesões , Colonografia Tomográfica Computadorizada/efeitos adversos , Neoplasias Colorretais/diagnóstico por imagem , Perfuração Intestinal/epidemiologia , Saúde Global , Humanos
9.
Eur Radiol ; 24(2): 519-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24192980

RESUMO

OBJECTIVES: This study evaluated the performance of a novel automated software tool for epicardial fat volume (EFV) quantification compared to a standard manual technique at coronary CT angiography (cCTA). METHODS: cCTA data sets of 70 patients (58.6 ± 12.9 years, 33 men) were retrospectively analysed using two different post-processing software applications. Observer 1 performed a manual single-plane pericardial border definition and EFVM segmentation (manual approach). Two observers used a software program with fully automated 3D pericardial border definition and EFVA calculation (automated approach). EFV and time required for measuring EFV (including software processing time and manual optimization time) for each method were recorded. Intraobserver and interobserver reliability was assessed on the prototype software measurements. T test, Spearman's rho, and Bland-Altman plots were used for statistical analysis. RESULTS: The final EFVA (with manual border optimization) was strongly correlated with the manual axial segmentation measurement (60.9 ± 33.2 mL vs. 65.8 ± 37.0 mL, rho = 0.970, P < 0.001). A mean of 3.9 ± 1.9 manual border edits were performed to optimize the automated process. The software prototype required significantly less time to perform the measurements (135.6 ± 24.6 s vs. 314.3 ± 76.3 s, P < 0.001) and showed high reliability (ICC > 0.9). CONCLUSIONS: Automated EFVA quantification is an accurate and time-saving method for quantification of EFV compared to established manual axial segmentation methods. KEY POINTS: • Manual epicardial fat volume quantification correlates with risk factors but is time-consuming. • The novel software prototype automates measurement of epicardial fat volume with good accuracy. • This novel approach is less time-consuming and could be incorporated into clinical workflow.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Pericárdio/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Software , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Design de Software
10.
Eur Radiol ; 24(7): 1537-46, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737530

RESUMO

OBJECTIVES: To evaluate the feasibility, image quality and radiation dose of prospectively ECG-triggered high-pitch coronary CT angiography (CCTA) with 30 mL contrast agent at 70 kVp. METHODS: Fifty-eight patients with suspected coronary artery disease, a body mass index (BMI) of less than 25 kg/m(2), sinus rhythm and a heart rate (HR) of less than 70 beats per minute (bpm) were prospectively enrolled in this study. Thirty mL of 370 mg I/mL iodinated contrast agent was administrated at a flow rate of 5 mL/s. All patients underwent prospectively ECG-triggered high-pitch CCTA on a second-generation dual-source CT system at 70 kVp using automated tube current modulation. RESULTS: Fifty-six patients (96.6%) had diagnostic CCTA images and two patients (3.4%) had one vessel with poor image quality each rated as non-diagnostic. No significant effects of HR, HR variability and BMI on CCTA image quality were observed (all P > 0.05). Effective dose was 0.17 ± 0.02 mSv and the size-specific dose estimate was 1.03 ± 0.13 mGy. CONCLUSION: Prospectively ECG-triggered high-pitch CCTA at 70 kVp with 30 mL of contrast agent can provide diagnostic image quality at a radiation dose of less than 0.2 mSv in patients with a BMI of less than 25 kg/m(2) and an HR of less than 70 bpm. KEY POINTS: • Prospectively ECG-triggered high-pitch CCTA at 70 kVp/30 mL contrast agent is feasible. • Diagnostic image quality can be obtained at a radiation dose of less than 0.2 mSv. • This protocol is suitable for normal-weight patients with slow heart rate.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia , Iohexol/análogos & derivados , Tomografia Computadorizada Multidetectores/métodos , Interpretação de Imagem Radiográfica Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/fisiopatologia , Estudos de Viabilidade , Feminino , Humanos , Injeções Intravenosas , Iohexol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Reprodutibilidade dos Testes
11.
AJR Am J Roentgenol ; 203(1): W70-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24951230

RESUMO

OBJECTIVE: The purpose of this article is to prospectively determine the value of stress dual-energy CT (DECT) myocardial perfusion imaging to coronary CT angiography (CTA) for the assessment of coronary artery disease (CAD) in a high-risk population. SUBJECTS AND METHODS: We prospectively enrolled 29 consecutive patients who were referred for cardiac SPECT examinations for known or suspected CAD to also undergo pharmacologic stress cardiac DECT. In 25 patients, cardiac catheterization was available as the reference standard for morphologically significant stenosis. The performance of coronary CTA alone, DECT myocardial perfusion alone, and the combination of both was assessed by calculating sensitivity, specificity, and AUC values. RESULTS: For morphologically significant stenosis, coronary CTA alone and myocardial DECT assessment alone had 95% sensitivity and 50% specificity. The combined approach yielded 100% sensitivity and 33% specificity if either was positive and 90% sensitivity and 67% specificity if both were positive. The AUC value was highest (0.78) if both were positive. For hemodynamically significant lesions, coronary CTA alone had 91% sensitivity and 38% specificity, and DECT alone had 95% sensitivity and 75% specificity. The combined approach yielded 100% sensitivity and 38% specificity if either was positive and 86% sensitivity and 75% specificity if both were positive. AUC values were highest for DECT alone (0.85) and the "both positive" evaluation (0.80). CONCLUSION: The combined analysis of coronary CTA and DECT myocardial perfusion reduces the number of false-positives in a high-risk population for CAD and outperforms the purely anatomic test of coronary CTA alone for the detection of morphologically and hemodynamically significant CAD.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Teste de Esforço/métodos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Adenosina , Cateterismo Cardíaco , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Feminino , Humanos , Iopamidol , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Purinas/administração & dosagem , Pirazóis/administração & dosagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Sensibilidade e Especificidade
12.
AJR Am J Roentgenol ; 203(2): W174-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24848691

RESUMO

OBJECTIVE: The purpose of this study was to determine the feasibility of global quantitative measurements of left ventricular myocardial perfusion derived from stress dynamic CT myocardial perfusion imaging. MATERIALS AND METHODS: The coronary CT angiographic and CT myocardial perfusion imaging datasets of 146 patients were visually evaluated for the presence of coronary artery stenosis and perfusion defects. For the quantitative analysis, volumes of interest were defined over the entire left ventricular myocardium to obtain global myocardial blood flow (MBF), myocardial blood volume (MBV), and volume transfer constant (K(trans)). RESULTS: In patients without anatomically significant coronary stenosis or perfusion defects, the mean value of global MBF was 137.9 ± 28.8 mL/100 mL/min; MBV, 19.5 ± 2.3 mL/100 mL; and K(trans), 85.8 ± 15.2 mL/100 mL/min. In patients with perfusion defects in one, two, or three vessels, the mean global MBF values were 132.6 ± 29.2, 117.4 ± 4.9, and 92.5 ± 11.2 mL/100 mL/min; MBV, 17.9 ± 3.2, 16.1 ± 3.1, and 12.8 ± 1.7 mL/100 mL; and K(trans), 80.4 ± 12.9, 76.6 ± 13.8, and 72.6 ± 15.5 mL/100 mL/min. In patients with significant (> 50%) stenosis in one, two, or three vessels at coronary CT angiography, the mean global MBF values were 129.2 ± 28.3, 120.5 ± 24.2, and 119.4 ± 33.5 mL/100 mL/min; MBV, 17.8 ± 3.3, 17.2 ± 3.2, and 14.7 ± 4.1 mL/100 mL; and K(trans), 80.3 ± 12.9, 76.0 ± 14.7, and 77.6 ± 13.2 mL/100 mL/min. CONCLUSION: Global quantitative assessment of left ventricular perfusion with stress dynamic CT myocardial perfusion imaging is feasible, and the findings correlate with the visual assessment of perfusion and the presence of coronary artery stenosis at coronary CT angiography. The potential clinical utility of this technique as a diagnostic tool for differentiating normal from globally reduced myocardial perfusion or as a prognostic marker merits further investigation.


Assuntos
Estenose Coronária/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Angiografia Coronária , Circulação Coronária , Estudos de Viabilidade , Feminino , Humanos , Imageamento Tridimensional , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos
13.
Circ J ; 78(5): 1216-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24632791

RESUMO

BACKGROUND: Growing evidence suggests that late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) is an additive marker of disease severity, and possibly of arrhythmic risk, in hypertrophic cardiomyopathy (HCM). We investigated the possible relationship between LGE and markers of myocardial repolarization dispersion in HCM. METHODS AND RESULTS: Eighty-five HCM outpatients underwent CMR and short-period electrocardiogram analysis to calculate the temporal myocardial repolarization dispersion through the QT variance normalized for QT mean (QTVN) and the QT variability index (QTVI). The QT dispersion in the spatial domain was also obtained. Patients with LGE (62%) had higher left atrial volume, maximum wall thickness, and left ventricular mass (P<0.0001), as well as a greater prevalence of non-sustained ventricular tachycardia (P<0.0001) and hypotensive blood pressure response (P=0.044). Both QTVN and QTVI were higher in the group with LGE (P<0.0001). At multivariate analysis, using QTVI as the dependent variable, %LGE (P<0.0001), age (P<0.0001), left ventricular outflow obstruction (P=0.038), and sudden cardiac death risk factor burden (P=0.020) reached statistical significance. Otherwise, only %LGE (P=0.005) and left ventricular mass index (P=0.015) remained associated with QTVN. CONCLUSIONS: Temporal myocardial repolarization dispersion correlates with LGE extent. Whether these variables could be useful in HCM clinical management warrants confirmation by larger prospective studies.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Eletrocardiografia , Gadolínio/administração & dosagem , Imageamento por Ressonância Magnética , Miocárdio , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/fisiopatologia
14.
Pediatr Radiol ; 44(9): 1158-68; quiz 1155-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25142330

RESUMO

Pulmonary venous anomalies comprise a wide spectrum of anatomical variations and their clinical presentations may vary from the relatively benign single partial anomalous pulmonary venous connection (PAPVC) to the critical obstructed total anomalous pulmonary venous connection (TAPVC). We briefly review the common anomalies encountered, while highlighting the utility that computed tomographic angiography (CTA) provides for this spectrum of extracardiac vascular malformations and connections. CTA has established itself as an invaluable imaging modality in these patients. A detailed knowledge of the CTA imaging findings in pulmonary venous anomalies is crucial to guide clinical decision-making in these patients.


Assuntos
Angiografia/métodos , Veias Pulmonares/anormalidades , Veias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Malformações Vasculares/diagnóstico por imagem , Humanos , Recém-Nascido , Síndrome de Cimitarra/diagnóstico por imagem
15.
Surg Endosc ; 27(6): 2058-67, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23292563

RESUMO

BACKGROUND: Laparoscopic surgery, despite its well-known advantages and continuous technological innovations, still has limitations such as the lack of tactile sensation and reduced view of the operative field. These limitations are particularly evident when performing laparoscopic colorectal resection due to the variability of the number and course of mesenteric vessels. Today, the patient's vascular anatomy can be mapped using computed tomography (CT) angiography and processing of the images with rendering software to reconstruct a three-dimensional model of the mesenteric vessels. To assess how prior knowledge of the patient's mesenteric vascular anatomy represents an advantage when performing laparoscopic colorectal resections, we conducted a randomized, parallel, single-blinded controlled trial. METHODS: From January 2010 to January 2012, all patients with surgical indication to undergo standardized right or left hemicolectomy and anterior rectal resections were randomly assigned to two groups and subjected to CT angiography with three-dimensional reconstruction of mesenteric vessels. In the first group the surgeon was able to view the 3D reconstruction before and during surgery, while in the second group the surgeon was only able to view the 3D reconstruction after surgery. RESULTS: Evaluation of data from 112 patients shows statistically significantly lower operative time, episodes of difficult identification of right anatomy, and incidence of intraoperative and postoperative complication related to difficult or erroneous identification of mesenteric vessels in the group in which the surgeon was able to view the 3D reconstruction before and during surgery compared with the control group. CONCLUSION: This study shows that prior knowledge of the patient's mesenteric vascular anatomy represents an advantage when performing laparoscopic colorectal resection.


Assuntos
Doenças do Colo/cirurgia , Laparoscopia/métodos , Artérias Mesentéricas/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem , Doenças Retais/cirurgia , Idoso , Angiografia/métodos , Colectomia/métodos , Doenças do Colo/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Masculino , Tomografia Computadorizada Multidetectores/métodos , Estudos Prospectivos , Doenças Retais/diagnóstico por imagem , Método Simples-Cego
16.
J Comput Assist Tomogr ; 37(4): 543-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23863529

RESUMO

PURPOSE: This study was designed to compare the radiation dose in abdominal dual-energy (DE) and single-energy (SE) acquisitions obtained in clinical practice with a second-generation DE computed tomography (DECT) and to analyze the dose variation in comparison with an SE acquisition performed with a 64-row SECT (SECT). METHODS: A total of 130 patients divided into 2 groups underwent precontrast and portal abdominal 128-row CT examination. In group A, DE portal acquisition was performed using a detector configuration of 2 × 40 × 0.6 mm, tube A at 80 kVp and a reference value of 559 mAs, tube B at 140 kVp and a reference value of 216 mAs, pitch 0.6, and online dose modulation; group B underwent SE portal acquisition using a detector configuration of 64 × 0.6 mm, 120 kVp and a reference value of 180 mAs, pitch 0.75, and online dose modulation. Group C consisted of 32 subjects from group A previously studied with 64-row SECT using the following parameters: detector configuration 64 × 0.6 mm, 120 kVp and a reference value of 180 mAs, pitch 0.75, and online dose modulation. In each group, the portal phase dose-length product and radiation dose (mSv) were calculated and normalized for a typical abdominal acquisition of 40 cm. RESULTS: After normalization to standard 40-cm acquisition, a dose-length product of 599.0 ± 133.5 mGy · cm (range, 367.5 ± 1231.2 mGy · cm) in group A, 525.9 ± 139.2 mGy · cm (range, 215.7-882.8 mGy · cm) in group B, and 515.9 ± 111.3 mGy · cm (range, 305.5-687.2 mGy · cm) in group C was calculated for portal phase acquisition.A significant radiation dose increase (P < 0.05) was observed in group A (10.2 ± 2.3 mSv) compared with group B (8.9 ± 2.4) and group C (8.8 ± 1.9 mSv). No significant difference (P > 0.05) was reported between SE 64- and 128-row acquisitions. A significant positive correlation between radiation dose and body mass index was observed in each group (group A, r = 0.59, P < 0.0001; group B, r = 0.35, P < 0.0001; group C, r = 0.20, P = 0.0098). CONCLUSIONS: In clinical practice, abdominal DECT acquisition shows a significant but minimal radiation dose increase, on the order of 1 mSv, compared with 64- and 128-row SE acquisition. The slightly increased radiation dose can be justified if the additional information obtained using a spectral imaging approach directly impacts on patient management or reduce the overall radiation dose with the generation of virtual unenhanced images, which can replace the precontrast acquisition.


Assuntos
Carga Corporal (Radioterapia) , Doses de Radiação , Radiografia Abdominal/estatística & dados numéricos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
17.
J Cardiovasc Comput Tomogr ; 17(2): 86-95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36934047

RESUMO

This review aims to summarize key articles published in the Journal of Cardiovascular Computed Tomography (JCCT) in 2022, focusing on those that had the most scientific and educational impact. The JCCT continues to expand; the number of submissions, published manuscripts, cited articles, article downloads, social media presence, and impact factor continues to grow. The articles selected by the Editorial Board of the JCCT in this review highlight the role of cardiovascular computed tomography (CCT) to detect subclinical atherosclerosis, assess the functional relevance of stenoses, and plan invasive coronary and valve procedures. A section is dedicated to CCT in infants and other patients with congenital heart disease, in women, and to the importance of training in CT. In addition, we highlight key consensus documents and guidelines published in JCCT last year. The Journal values the tremendous work by authors, reviewers, and editors to accomplish these contributions.


Assuntos
Estenose da Valva Aórtica , Sistema Cardiovascular , Substituição da Valva Aórtica Transcateter , Feminino , Humanos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Angiografia por Tomografia Computadorizada , Constrição Patológica , Coração , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X/métodos , Substituição da Valva Aórtica Transcateter/métodos
18.
AJR Am J Roentgenol ; 199(5 Suppl): S98-S105, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23097174

RESUMO

OBJECTIVE: Dual-energy CT (DECT) is an innovative imaging technique that operates on the basic principle of application of two distinct energy settings that make the transition from CT attenuation-based imaging to material-specific or spectral imaging. The purpose of this review is to describe the use of DECT in oncology. CONCLUSION: Applications of DECT in clinical practice are based on two capabilities: material differentiation and material identification and quantification. The capability of obtaining different material-specific datasets (iodine map, virtual unenhanced, and monochromatic images) in the same acquisition can improve lesion detection and characterization. This approach can also affect evaluation of the response to therapy and detection of oncology-related disorders. DECT is an innovative imaging technique that can dramatically affect the care of oncologic patients.


Assuntos
Neoplasias/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos
19.
J Imaging ; 8(2)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200737

RESUMO

Ischemic chronic cardiomyopathy (ICC) is still one of the most common cardiac diseases leading to the development of myocardial ischemia, infarction, or heart failure. The application of several imaging modalities can provide information regarding coronary anatomy, coronary artery disease, myocardial ischemia and tissue characterization. In particular, coronary computed tomography angiography (CCTA) can provide information regarding coronary plaque stenosis, its composition, and the possible evaluation of myocardial ischemia using fractional flow reserve CT or CT perfusion. Cardiac magnetic resonance (CMR) can be used to evaluate cardiac function as well as the presence of ischemia. In addition, CMR can be used to characterize the myocardial tissue of hibernated or infarcted myocardium. Echocardiography is the most widely used technique to achieve information regarding function and myocardial wall motion abnormalities during myocardial ischemia. Nuclear medicine can be used to evaluate perfusion in both qualitative and quantitative assessment. In this review we aim to provide an overview regarding the different noninvasive imaging techniques for the evaluation of ICC, providing information ranging from the anatomical assessment of coronary artery arteries to the assessment of ischemic myocardium and myocardial infarction. In particular this review is going to show the different noninvasive approaches based on the specific clinical history of patients with ICC.

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