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1.
JAMA Netw Open ; 3(1): e1920084, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31995217

RESUMO

Importance: Errors and adverse events occur frequently in health care. Three-dimensional (3-D) laparoscopic systems claim to provide more realistic depth perception and better spatial orientation compared with their 2-D counterparts. Objective: To compare the association of 3-D vs 2-D systems with technical performance during laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures using a multiport intraoperative data capture system. Design, Setting, and Participants: This cohort study was performed between May and December 2018, with a total of 50 LRYGB procedures performed in an academic tertiary care center; recordings of the operations were evaluated with a 30-day follow-up. All procedures were performed by the same surgical team. Exposure: Surgical teams used 2-D or 3-D laparoscopic systems. Main Outcomes and Measures: Technical performance was evaluated using the Objective Structured Assessment of Technical Skill and surgical errors and events using the Generic Error Rating Tool. Results: Of the 50 patients who underwent LRYGB procedures, 42 (86%) were women, with a median (interquartile range) age of 42 (35-47) years and a median (interquartile range) body mass index of 46 (42-48), with no significant demographic differences between the groups whose operations were performed using the 2-D and 3-D systems. The mean (SD) number of errors per case was significantly lower in procedures using the 3-D laparoscopic system than in those using the 2-D system (17 [6] vs 33 [2]; P < .001). The mean (SD) number of error-related events was significantly lower in procedures using the 3-D system than in those using the 2-D system (6 [2] vs 11 [4]; P < .001). Mean (SD) Objective Structured Assessment of Technical Skill scores were significantly higher when the 3-D system was used than when the 2-D system was used (28 [4] vs 22 [3]; P < .001). Conclusions and Relevance: In this limited sample of LRYGB procedures, the use of a 3-D laparoscopic system was associated with a statistically significant reduction in errors and events as well as higher Objective Structured Assessment of Technical Skill scores compared with 2-D systems.


Assuntos
Derivação Gástrica/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagem Tridimensional/métodos , Laparoscopia/métodos , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Ultrasonics ; 101: 106001, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31505328

RESUMO

Ultrasound is the first-line tool for screening hepatic steatosis. Statistical distributions can be used to model the backscattered signals for liver characterization. The Nakagami distribution is the most frequently adopted model; however, the homodyned K (HK) distribution has received attention due to its link to physical meaning and improved parameter estimation through X- and U-statistics (termed "XU"). To assess hepatic steatosis, we proposed HK parametric imaging based on the α parameter (a measure of the number of scatterers per resolution cell) calculated using the XU estimator. Using a commercial system equipped with a 7-MHz linear array transducer, phantom experiments were performed to suggest an appropriate window size for α imaging using the sliding window technique, which was further applied to measuring the livers of rats (n = 66) with hepatic steatosis induced by feeding the rats a methionine- and choline-deficient diet. The relationships between the α parameter, the stage of hepatic steatosis, and histological features were verified by the correlation coefficient r, one-way analysis of variance, and regression analysis. The phantom results showed that the window side length corresponding to five times the pulse length supported a reliable α imaging. The α parameter showed a promising performance for grading hepatic steatosis (p < 0.05; r2 = 0.68). Compared with conventional Nakagami imaging, α parametric imaging provided significant information associated with fat droplet size (p < 0.05; r2 = 0.53), enabling further analysis and evaluation of severe hepatic steatosis.


Assuntos
Fígado Gorduroso/diagnóstico por imagem , Ultrassonografia/métodos , Animais , Modelos Animais de Doenças , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Imagens de Fantasmas , Ratos , Ratos Wistar
3.
Forensic Sci Int ; 307: 110119, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31869652

RESUMO

It is important that fingermark enhancement techniques are safe and simple to carry out. Many chemicals are widely used to enhance and develop bloody fingermark. However, the use of natural products for fingermark detection and examination has several advantages and challenges. In this study, Lac dye (Laccifer lacca) was used to enhance bloody fingermarks on various types of non-porous and porous materials. Bloody fingermarks were deposited using a depletion series technique on eleven different surfaces. To assess the efficiency of Lac dye stain, comparisons were performed with Amido black stain as a reference method. Results revealed the similarity between Lac dye and Amido black on non-porous materials, in terms of both fingermark grades, and color intensity. However, Lac dye showed relatively low performance for enhancing and developing bloody fingermarks on porous materials. This indicates that Lac dye can be beneficially used as an alternative to chemicals such as Amido black on a non-porous surface. Further study into Lac dye formulation on porous materials is recommended.


Assuntos
Compostos Azo , Manchas de Sangue , Dermatoglifia , Aumento da Imagem/métodos , Corantes , Humanos , Masculino , Naftalenossulfonatos , Porosidade
4.
Medicine (Baltimore) ; 98(44): e17738, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689821

RESUMO

This study aimed to evaluate a novel real-time rotational optical coherence tomography (OCT) imaging system (OCTIS) with a fiber-optic probe to look at endometrium and to correlate the OCTIS images with standard histology. OCT could obtain real-time images resembling histological examination. With recent development of customized probes, it allows OCT to be used in the field of gynecology.This is a pilot, prospective, ex-vivo and observational study. Women underwent hysterectomy for various gynecological conditions were recruited and OCTIS images were obtained from endometrium of 15 fresh uterus specimens immediately after hysterectomy. The excised uterus was cut open and OCTIS imaging was obtained. The scanned region of endometrium was excised for histological examination and OCTIS images were precisely compared to corresponding histological images and ultrasound images. Blinded qualitative analysis on OCTIS images was performed by 2 assessors to determine inter-rating reliability on the histopathological diagnosis.Epithelium, glands, cysts, and stroma of endometrium were clearly seen by the OCTIS. Different phases of menstrual cycle of normal endometrium could be differentiated and pathological condition such as hyperplastic and dysplasic endometrium, which corresponded well with histological findings, could be identified. The inter-rater reliability between assessors on overall OCTIS endometrium and neoplastic OCTIS endometrium was moderate (Kendall τb of 0.58) and substantial (Kendall τb of 0.76), respectively.OCTIS can provide real-time, high-resolution and rotational imaging modality to view endometrial structure with high consistency with histological examination and satisfactory agreement between observers. It has a great potential to be developed in the clinical use of endometrial assessment for gynecological applications.


Assuntos
Hiperplasia Endometrial/diagnóstico por imagem , Endométrio/diagnóstico por imagem , Aumento da Imagem/métodos , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Endométrio/patologia , Feminino , Humanos , Histerectomia , Aumento da Imagem/instrumentação , Pessoa de Meia-Idade , Variações Dependentes do Observador , Projetos Piloto , Período Pós-Operatório , Estudos Prospectivos , Reprodutibilidade dos Testes , Método Simples-Cego , Tomografia de Coerência Óptica/instrumentação
5.
Medicine (Baltimore) ; 98(48): e18101, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770231

RESUMO

This retrospective study aimed to improve the diagnostic accuracy of breast lymphoma (BL) by analyzing the findings of BL on mammography and magnetic resonance imaging (MRI).Fifteen patients with breast lymphoma (BL, Primary/Secondary: 13/2) were confirmed by pathology. The imaging findings of those patients were analyzed by 2 senior radiologists.BL commonly showed significant enhancement with penetrating vessels and septation in masses on dynamic contrast-enhanced MRI (DCE-MRI). Diffusion limitation of BL is more pronounced than breast cancer on diffusion weighted imaging.The study suggests that the penetrating vessels and diffusion restriction of lesions are helpful for the diagnosis and differential diagnosis of BL.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Aumento da Imagem/métodos , Linfoma/diagnóstico por imagem , Imagem por Ressonância Magnética/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Adulto , Meios de Contraste , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/estatística & dados numéricos , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Mamografia/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Medicine (Baltimore) ; 98(48): e18207, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770279

RESUMO

Few indexes are available for nuclear medicine image quality assessment, particularly for respiratory blur assessment. A variety of methods for the identification of blur parameters has been proposed in literature mostly for photographic pictures but these methods suffer from a high sensitivity to noise, making them unsuitable to evaluate nuclear medicine images. In this paper, we aim to calibrate and test a new blur index to assess image quality.Blur index calibration was evaluated by numerical simulation for various lesions size and intensity of uptake. Calibrated blur index was then tested on gamma-camera phantom acquisitions, PET phantom acquisitions and real-patient PET images and compared to human visual evaluation.For an optimal filter parameter of 9, non-weighted and weighted blur index led to an automated classification close to the human one in phantom experiments and identified each time the sharpest image in all the 40 datasets of 4 images. Weighted blur index was significantly correlated to human classification (ρ = 0.69 [0.45;0.84] P < .001) when used on patient PET acquisitions.The provided index allows to objectively characterize the respiratory blur in nuclear medicine acquisition, whether in planar or tomographic images and might be useful in respiratory gating applications.


Assuntos
Aumento da Imagem/métodos , Medicina Nuclear , Tomografia por Emissão de Pósitrons , Algoritmos , Humanos , Medicina Nuclear/métodos , Medicina Nuclear/normas , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/normas , Razão Sinal-Ruído
7.
Med Sci Monit ; 25: 5992-5996, 2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31401642

RESUMO

BACKGROUND To determine if ADC and DCE-MRI can be used to differentiate angiomatous meningiomas (AMs) from solitary fibrous tumors/hemangiopericytomas (SFT/HPCs). MATERIAL AND METHODS We retrospectively reviewed records of 103 patients from 1 January 1 2014 to 1 November 2018. We enrolled 41 patients who had undergone a 3T MRI, with histologically confirmed AMs in 20 (48.80%) patients, and SFT/HPCs in 21 (51.20%) patients. The ADC and DCE-MRI features were derived and then compared by 2 independent-samples t tests and Wilcoxon rank sum test to obtain the ROC. RESULTS AMs had significantly lower ADC values than did SFT/HPCs, but AMs had significantly higher MCER values than did SFT/HPCs. A threshold value of 1.03×10⁻³ mm²/s for ADC to predict AMs from SFT/HPCs was estimated (AUC=0.902, sensitivity=88.20%, specificity=83.30%). Optimal diagnostic performance (AUC=0.825, sensitivity=84.60%, specificity=81.80%) was obtained when setting MCER=226.7% as the threshold value. CONCLUSIONS The ADC values of AMs were lower than those of SFT/HPCs; the MCER of AMs were greater than those of SFT/HPCs, and ADC was more useful than MCER, and these parameters could help diagnosis.


Assuntos
Hemangiopericitoma/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Tumores Fibrosos Solitários/diagnóstico por imagem , China , Meios de Contraste , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Jpn J Radiol ; 37(10): 701-709, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401722

RESUMO

OBJECTIVES: To evaluate quantitative three-dimensional (3D) dynamic contrast-enhanced ultrasound (DCE-US) in the assessment of tumor angiogenesis using an orthotropic liver tumor model. METHODS: Nine New Zealand white rabbits with liver orthotropic VX2 tumors were established and imaged by two-dimensional (2D) and 3D DCE-US after SonoVue® bolus injections. The intraclass correlation coefficients of perfusion parameters, including peak intensity (PI), mean transit time, time to peak, and area under the curve, were calculated based on time-intensity curve. The percentage area of microvascular (PAMV) and the expression of vascular endothelial growth factor (VEGF) were both evaluated by immunohistochemical analysis and weighted by the tumor activity area ratio. Correlations between quantitative and histologic parameters were analyzed. RESULTS: The reproducibility of 3D DCE-US quantitative parameters was excellent (ICC 0.91-0.99); but only PI showed high reproducibility (ICC 0.97) in 2D. None of the parameters of quantitative 2D DCE-US were significantly correlated with weighted PAMV or VEGF. For 3D DCE-US, there was a positive correlation between PI and weighted PAMV (r = 0.74, P = 0.04) as well as VEGF (r = 0.79, P = 0.02). CONCLUSION: Quantitative parameters of 3D DCE-US show feasibility, higher reproducibility and accuracy for the assessment of tumor angiogenesis using an orthotropic liver tumor model compared with 2D DCE-US.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Imagem Tridimensional/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Ultrassonografia/métodos , Animais , Modelos Animais de Doenças , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/patologia , Neovascularização Patológica/patologia , Coelhos , Reprodutibilidade dos Testes
11.
Biomed Res Int ; 2019: 3843295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467888

RESUMO

Breast cancer is a main cause of disease and death for women globally. Because of the limitations of traditional mammography and ultrasonography, magnetic resonance imaging (MRI) has gradually become an important radiological method for breast cancer assessment over the past decades. MRI is free of the problems related to radiation exposure and provides excellent image resolution and contrast. However, a disadvantage is the injection of contrast agent, which is toxic for some patients (such as patients with chronic renal disease or pregnant and lactating women). Recent findings of gadolinium deposits in the brain are also a concern. To address these issues, this paper develops an intravoxel incoherent motion- (IVIM-) MRI-based histogram analysis approach, which takes advantage of several hyperspectral techniques, such as the band expansion process (BEP), to expand a multispectral image to hyperspectral images and create an automatic target generation process (ATGP). After automatically finding suspected targets, further detection was attained by using kernel constrained energy minimization (KCEM). A decision tree and histogram analysis were applied to classify breast tissue via quantitative analysis for detected lesions, which were used to distinguish between three categories of breast tissue: malignant tumors (i.e., central and peripheral zone), cysts, and normal breast tissues. The experimental results demonstrated that the proposed IVIM-MRI-based histogram analysis approach can effectively differentiate between these three breast tissue types.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Meios de Contraste/uso terapêutico , Feminino , Humanos , Imagem Tridimensional/métodos , Mamografia/métodos
12.
Eur J Radiol ; 118: 51-57, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31439258

RESUMO

PURPOSE: To test the potential impact of pharmacokinetic parameters, derived from DCE-MRI analysis, on the diagnostic performance of PI-RADSv.2 classification in prostate lesions characterization. METHOD: Among patients who underwent multiparametric prostate MRI (mpMRI) (January 2016-March 2018) followed by histological evaluation (targeted biopsies/prostatectomy), 103 men were retrospectively selected. For each patient the index lesion was identified and pharmacokinetic parameters (Ktrans, Kep, Ve, Vp) were assessed. MRI diagnostic performance in the detection of significant tumors [Gleason Score (GS)≥7] was assessed, considering PI-RADS≥3 as positive. RESULTS: GS ≥ 7 (n = 59) showed higher Ktrans (p < 0.01) and Kep (p = 0.01) compared to GS < 7. At ROC curve analysis, a Ktrans cut-off of 191 × 10-3/min was identified to predict the presence of GS ≥ 7 (AUC:0.75; sensitivity:95%; specificity:61%). Sensitivity and PPV of mpMRI using PI-RADSv.2 were 98% and 61%. Reclassifying PI-RADS≥3 lesions according to Ktrans cut-off, 22 false positives were shifted to true negatives with 3 false negative findings; PPV raised to 79%. Appling Ktrans cut-off to PI-RADS 3 lesions of peripheral zone (n = 18), 12 true negatives, 4 true positives, 2 false positives were identified. CONCLUSIONS: Despite its high sensitivity prostate mpMRI generates many false positive cases: Ktrans in addition to PIRADS v.2 seems to improve MRI-PPV and may help in avoiding redundant biopsies.


Assuntos
Meios de Contraste/farmacocinética , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Avaliação como Assunto , Reações Falso-Positivas , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/patologia , Curva ROC , Sistemas de Informação em Radiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
J Med Ultrason (2001) ; 46(4): 449-458, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377939

RESUMO

PURPOSE: Histological grading is important for the treatment algorithm in pancreatic neuroendocrine neoplasms (PNEN). The present study examined the efficacy of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) and time-intensity curve (TIC) analysis of PNEN diagnosis and grading. METHODS: TIC analysis was performed in 30 patients using data obtained from CH-EUS, and a histopathological diagnosis was made via EUS-guided fine-needle aspiration or surgical resection. The TIC parameters were analyzed by dividing them into G1/G2 and G3/NEC groups. Then, patients were classified into non-aggressive and aggressive groups and evaluated. RESULTS: Twenty-six patients were classified as G1/G2, and four as G3/NEC. From the TIC analysis, five parameters were obtained (I: echo intensity change, II: time for peak enhancement, III: speed of contrast, IV: decrease rate for enhancement, and V: enhancement ratio for node/pancreatic parenchyma). Three of these parameters (I, IV, and V) showed high diagnostic performance. Using the cutoff value obtained from the receiver-operating characteristic (ROC) analysis, the correct diagnostic rates of parameters I, IV, and V were 96.7%, 100%, and 100%, respectively, between G1/G2 and G3/NEC. A total of 21 patients were classified into the non-aggressive group, and nine into the aggressive group. Using the cutoff value obtained from the ROC analysis, the accurate diagnostic rates of I, IV, and V were 86.7%, 86.7%, and 88.5%, respectively, between the non-aggressive and aggressive groups. CONCLUSION: CH-EUS and TIC analysis showed high diagnostic accuracy for grade diagnosis of PNEN. Quantitative perfusion analysis is useful to predict PNEN grade diagnosis preoperatively.


Assuntos
Meios de Contraste , Endossonografia/métodos , Aumento da Imagem/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Curva ROC , Estudos Retrospectivos
14.
Neural Netw ; 118: 310-320, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326663

RESUMO

Accounting for the morphology of shale formations, which represent highly heterogeneous porous media, is a difficult problem. Although two- or three-dimensional images of such formations may be obtained and analyzed, they either do not capture the nanoscale features of the porous media, or they are too small to be an accurate representative of the media, or both. Increasing the resolution of such images is also costly. While high-resolution images may be used to train a deep-learning network in order to increase the quality of low-resolution images, an important obstacle is the lack of a large number of images for the training, as the accuracy of the network's predictions depends on the extent of the training data. Generating a large number of high-resolution images by experimental means is, however, very time consuming and costly, hence limiting the application of deep-learning algorithms to such an important class of problems. To address the issue we propose a novel hybrid algorithm by which a stochastic reconstruction method is used to generate a large number of plausible images of a shale formation, using very few input images at very low cost, and then train a deep-learning convolutional network by the stochastic realizations. We refer to the method as hybrid stochastic deep-learning (HSDL) algorithm. The results indicate promising improvement in the quality of the images, the accuracy of which is confirmed by visual, as well as quantitative comparison between several of their statistical properties. The results are also compared with those obtained by the regular deep learning algorithm without using an enriched and large dataset for training, as well as with those generated by bicubic interpolation.


Assuntos
Aprendizado Profundo , Aumento da Imagem/métodos , Imagem Tridimensional/métodos , Processos Estocásticos
15.
Radiol Med ; 124(12): 1306-1314, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31317380

RESUMO

The purpose of this study was to determine whether MRE performed with diffusion-weighted imaging (DWI) sequences is comparable to contrast-enhanced MRE in the detection of active small-bowel inflammation in pediatric patients with Crohn's disease (CD). We included in our study 68 patients with diagnosis of CD between April 2015 and June 2018 that underwent MRE examination. Examination protocol includes coronal and axial FISP, T2-w half-Fourier RARE and DWI sequences, a baseline coronal T1-w fat-saturated ultrafast (GRE) sequence followed by contrast 3D T1-w GRE. All images were assessed by two radiologists who graded each of bowel segments for the presence of inflammation on a four-point confidence scale on the basis of wall thickening and wall signal on DWI and ADC maps and comparing their results with post-contrast images. When considering all bowel segments, we found 41 true positive and 25 true negative on DWI. One false positive case corresponded to the absence of inflammatory histopathology changes at the level of the terminal ileum in a 15-year-old male, and one false negative case was in a 10-year-old female with only jejunal lesion. The corresponding sensitivity, specificity, PPV, NPV and accuracy were 97.6% (95% CI 67.7-99.7), 96.1% (95% CI 66.7-98.5), 97.6% (95% CI 70.8-98.4), 96.1% (95% CI 64.2-90.6) and 97% (95% CI 84.2-97.5), respectively. Analyzing the gadolinium-enhanced set, 35 true positive and 25 true negative results were found. One false positive case was found, and it was the same as with DWI. The corresponding sensitivity, specificity, PPV, NPV and accuracy were 83.3% (95% CI 65.9-86.7), 96.1% (95% CI 68.7-88.9), 97.2% (95% CI 84.3-98.7), 78.1% (95% CI 27.9-72.1) and 88.2% (95% CI 41.2-85.6), respectively. Sensitivity for the detection of active IBD lesion was significantly better with DWI than with CE-T1-w imaging (p = 0.002), whereas the specificity was similar (p = 0.743). Our study has shown that DWI sequences have a high accuracy in detecting the bowel segment affected by CD. These results emphasize the utility to include the DWI/ADC in standard MR enterography protocols and suggest that DWI could replace T1-weighted post-contrast sequences.


Assuntos
Doença de Crohn/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Aumento da Imagem/métodos , Intestinos/diagnóstico por imagem , Adolescente , Criança , Meios de Contraste , Doença de Crohn/patologia , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Gadolínio , Humanos , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
16.
Jpn J Radiol ; 37(9): 651-659, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31321619

RESUMO

PURPOSE: To determine the consistency of major hepatocellular carcinoma (HCC) features between CT and MRI based on Liver Imaging Reporting and Data System (LI-RADS) v2018 and to investigate the additional value on gadoxetic acid-enhanced MRI. MATERIALS AND METHODS: Patients who underwent dynamic CT and gadoxetic acid-enhanced MRI within 1 month were investigated. Two radiologists evaluated the presence of major HCC features and categorized observations using LI-RADS v2018 algorithm. In addition, each observation was recorded as hyper-, iso-, or hypo-intensity on hepatobiliary-phase (HBP) images. RESULTS: Sixty-one patients with 110 observations were identified. Among 88 observations classified as LR-3, 4 or 5, arterial phase hyper-enhancement and washout appearance showed higher frequencies on CT than on MRI (75.0% vs. 58.0%, P < 0.001, and 60.2% vs. 44.3%, P = 0.014, respectively). Of the 59 LR-3 observations categorized on MRI, 70.0% of observations with hypo-intensity on HBP images were HCCs, whereas 89.5% of observations with iso- or hyper-intensity on HBP images were non-HCCs (P < 0.001) CONCLUSION: The frequencies of arterial phase hyper-enhancement and washout appearances were higher on CT than on gadoxetic acid-enhanced MRI. For LR-3 observations, adding the hepatobiliary-phase hypo-intensity to major features improved the diagnostic performance of MRI in distinguishing HCCs from non-HCC lesions.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Gadolínio DTPA , Aumento da Imagem/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Sistemas de Informação em Radiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Meios de Contraste , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
17.
Magn Reson Imaging Clin N Am ; 27(3): 427-437, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279447

RESUMO

Cardiac MR (CMR) imaging contributes uniquely to the comprehensive assessment and management of aortic stenosis (AS), beyond the information provided by transthoracic echocardiography. The severity of AS and subsequent ventricular remodeling response can be assessed using cine images and phase-contrast mapping. CMR imaging also identifies myocardial tissue characteristics, which are valuable markers of left ventricular decompensation and adverse outcomes in AS. CMR imaging may be used as an alternative modality for transcatheter aortic valve replacement (TAVR) planning and post-TAVR management. This article explores the clinical utility of CMR imaging evaluation.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Coração/diagnóstico por imagem , Coração/fisiopatologia , Imagem por Ressonância Magnética/métodos , Substituição da Valva Aórtica Transcateter , Velocidade do Fluxo Sanguíneo/fisiologia , Meios de Contraste , Gadolínio , Humanos , Aumento da Imagem/métodos , Imagem Cinética por Ressonância Magnética , Índice de Gravidade de Doença , Remodelação Ventricular/fisiologia
18.
Magn Reson Imaging Clin N Am ; 27(3): 475-490, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279451

RESUMO

Cardiac magnetic resonance (CMR) imaging has gained significant traction as an imaging modality of choice in the evaluation of individuals with, or at risk for, heart failure. Ventricular arrhythmias, often malignant, may be sequelae of heart failure and arise from fibrosis. Late gadolinium enhancement evaluation by CMR has become a preferred modality to assess individuals at risk for malignant ventricular arrhythmias. A spectrum of various pathologies that predispose individuals to malignant ventricular arrhythmias, as well as the usefulness of CMR in their identification and prognostication, are reviewed.


Assuntos
Arritmias Cardíacas/diagnóstico , Meios de Contraste , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos , Arritmias Cardíacas/fisiopatologia , Humanos
19.
Magn Reson Imaging Clin N Am ; 27(3): 545-561, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279456

RESUMO

Late gadolinium enhancement (LGE) has become a standard clinical tool to evaluate myocardial fibrosis to define myocardial viability in the context of ischemic myocardial disease. More recently, LGE has also been used to characterize the presence and pattern of fibrosis in nonischemic cardiomyopathies. It yields unique and valuable diagnostic and prognostic insights for myriad nonischemic clinical indications and has become a key part of routine cardiac MR imaging, and a tool to guide treatment. This article reviews the technical aspects of LGE performance and its diagnostic and prognostic implications in nonischemic cardiomyopathy.


Assuntos
Meios de Contraste/farmacocinética , Gadolínio/farmacocinética , Cardiopatias/diagnóstico por imagem , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos , Humanos , Prognóstico , Reprodutibilidade dos Testes
20.
Can Assoc Radiol J ; 70(3): 239-245, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272725

RESUMO

PURPOSE: Late gadolinium hyperintensity (LGH) is sometimes seen in colorectal liver metastasis (CRLM) and represents a significant diagnostic pitfall due to overlap with LGH in benign hemangiomas; therefore, the objective of this study was to determine the prevalence of LGH and the ability of LGH to differentiate between CRLM and benign lesions with intravascular (gadofosveset) vs extracellular contrast agents (gadobutrol). METHODS: Patients with known colorectal cancer and suspected liver lesions were prospectively recruited into this institutional review board-approved, single institution study and received magnetic resonance imaging of the liver with gadofosveset and gadobutrol. The prevalence of LGH for CRLMs and solid benign lesions was determined. Receiver operating characteristics curves were determined for the presence of LGH as a predictor of benignity. The utility of LGH to differentiate between CRLM and solid benign lesions using gadofosveset vs gadobutrol was compared using the generalized estimating equation. RESULTS: Twenty-five patients with 131 solid focal liver lesions were recruited. The prevalence of LGH of CRLMs was 11.2% (95% confidence interval [CI]: 0.5%-21.8%) with gadofosveset vs 63.7% (95% CI: 45.7%-81.7%) with gadobutrol. The area under the receiver operating characteristic curve for the presence of LGH as a predictor of benignity was 0.86 using gadofosveset vs 0.75 using gadobutrol. Both LGH (P = .003) and the interaction of contrast agent and LGH (P = .003) statistically significantly differentiated CRLM from benign lesions. CONCLUSION: LGH is more common with extracellular than with intravascular contrast agents and is statistically significantly associated with benign lesions rather than metastases.


Assuntos
Neoplasias Colorretais/patologia , Meios de Contraste , Gadolínio , Aumento da Imagem/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Imagem por Ressonância Magnética/métodos , Compostos Organometálicos , Adulto , Idoso , Tomada de Decisão Clínica , Diagnóstico Diferencial , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
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