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1.
Artigo em Inglês | MEDLINE | ID: mdl-38518086

RESUMO

OBJECTIVE: To quantitatively analyze the morphological characteristics of osteophytes in DISH and syndesmophytes in AS, and summarize different ossification patterns to help identify the two diseases. Associated factors for new bone formation would be investigated. METHODS: Fifty patients with DISH and 50 age-, sex-, CT examination site- matched patients with AS were enrolled. Radiographic and clinical data were reviewed. Osteophytes (syndesmophytes) in front of each vertebral body and the corresponding intervertebral disc space were defined as vertebral osteophytes unit (VOU). The volume, angle and location (contralateral, ipsilateral, bilateral) of osteophytes in each VOU were measured and compared between DISH and AS groups. RESULTS: In each VOU, the volume and angle of osteophytes in DISH were significantly larger. The best osteophytes volume and angle cutoff value in predicting DISH was 0.59 cm3 and 40.15°. Contralateral, bilateral, ipsilateral osteophytes were recorded in 59.32%, 36.38%, 4.3% of assessed VOUs in patients with DISH and 64.78%, 29.31%, 5.91% in AS (p<0.001), respectively. As to ipsilateral osteophytes, the volume was inversely correlated with the center of the vertebral body to the center of the descending aorta (DISH: r = -0.45, p= 0.01; AS: r = -0.83, p<0.001). Advanced age, disease duration, smoking and overweight contribute to the progression of osteophytes and syndesmophytes. CONCLUSION: Morphological features of osteophytes are helpful to distinguish DISH with AS. Aortic pulsations inhibit or hinder new bone formation in both DISH and AS. Maintaining normal BMI could postpone osteophytes formation.

2.
Asian Pac J Allergy Immunol ; 36(1): 51-57, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28577522

RESUMO

BACKGROUND: A proportion of cases of Rosai-Dorfman disease exhibit some histological features consistent with IgG4-related disease (IgG4RD). Several investigators have discussed whether Rosai-Dorfman disease belongs to the spectrum of IgG4RD or is concurrent with it by coincidence. OBJECTIVE: To elucidate the relationship between the two diseases, we report key features, including IgG4 and amyloid levels, of four cases of Rosai-Dorfman disease in the breast. METHODS: The histological features of the four cases were analyzed and the numbers of IgG4+ plasma cells and IgG4/IgG ratios were evaluated. Serum IgG4 concentrations were also measured in two recent cases. A literature review was also performed. RESULTS: Two cases (case 1 and 2) showed features of IgG4RD, including lymphoid follicle formation with regressive changes, obliterative phlebitis, increased number of IgG4+ plasma cells, and increased IgG4/IgG ratio; one of the two had an elevated serum IgG4 level. Amyloidosis was detected in these cases, with amyloid in the stroma and the vessel walls of the lesion. The other two cases (case 3 and 4) only had mild increases in the numbers of IgG4+ plasma cells, while amyloid was deposited in the stroma only. CONCLUSIONS: A subset of Rosai-Dorfman disease may overlap with IgG4RD in the breast. When Rosai-Dorfman disease has features of IgG4RD, amyloidosis could be induced in the lesion.


Assuntos
Doenças Mamárias/patologia , Histiocitose Sinusal/patologia , Doença Relacionada a Imunoglobulina G4/patologia , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
3.
Heart Surg Forum ; 20(1): E026-E031, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28263147

RESUMO

OBJECTIVE: The aim of this study was to quantify left ventricular torsion by newly applied cardiovascular magnetic resonance feature tracking (CMR-FT), and to evaluate the clinical value of the ventricular torsion as a sensitive indicator of cardiac function by comparison of preoperative and postoperative torsion. METHODS: A total of 54 volunteers and 36 patients with previous myocardial infarction (MI) and LV ejection fraction (EF) between 30%-50% were screened preoperatively or postoperatively by MRI. The patients' short axis views of the whole heart were acquired, and all patients had a scar area >75% in at least one of the anterior or inferior segments. Their apical and basal rotation values were analyzed by feature tracking, and the correlation analysis was performed for the improvement of LV torsion and ejection fraction after CABG. The intra- and inter-observer reliabilities of torsion measured by CMR-FT were assessed. RESULTS: In normal hearts, the apex rotated counterclockwise in the systolic period with the peak rotation as 10.2 ± 4.8°, and the base rotated clockwise as the peak value was 7.0 ± 3.3°. There was a timing hiatus between the apex and base untwisting, during which period the heart recoils and its suction sets the stage for the following rapid filling period. The postoperative torsion and rotation significantly improved compared with preoperative ones. However, the traditional indicator of cardiac function, ejection fraction, didn't show significant improvement. CONCLUSION: Left ventricular torsion derived from CMR-FT, which does not require specialized CMR sequences, was sensitive to patients with low ejection fraction whose cardiac function significantly improved after CABG. The rapid acquisition of this measurement has potential for the assessment of cardiac function in clinical practice.


Assuntos
Ponte de Artéria Coronária , Ventrículos do Coração/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/cirurgia , Função Ventricular Esquerda/fisiologia , Adulto , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Período Pós-Operatório , Curva ROC , Reprodutibilidade dos Testes , Volume Sistólico/fisiologia
4.
IEEE Trans Med Imaging ; 43(4): 1476-1488, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38048240

RESUMO

Accurate vascular segmentation from High Resolution 3-Dimensional (HR3D) medical scans is crucial for clinicians to visualize complex vasculature and diagnose related vascular diseases. However, a reliable and scalable vessel segmentation framework for HR3D scans remains a challenge. In this work, we propose a High-resolution Energy-matching Segmentation (HrEmS) framework that utilizes deep learning to directly process the entire HR3D scan and segment the vasculature to the finest level. The HrEmS framework introduces two novel components. Firstly, it uses the real-order total variation operator to construct a new loss function that guides the segmentation network to obtain the correct topology structure by matching the energy of the predicted segment to the energy of the manual label. This is different from traditional loss functions such as dice loss, which matches the pixels between predicted segment and manual label. Secondly, a curvature-based weight-correction module is developed, which directs the network to focus on crucial and complex structural parts of the vasculature instead of the easy parts. The proposed HrEmS framework was tested on three in-house multi-center datasets and three public datasets, and demonstrated improved results in comparison with the state-of-the-art methods using both topology-relevant and volumetric-relevant metrics. Furthermore, a double-blind assessment by three experienced radiologists on the critical points of the clinical diagnostic processes provided additional evidence of the superiority of the HrEmS framework.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
5.
Tumour Biol ; 34(3): 1537-45, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23397543

RESUMO

The purpose of this study was to investigate the diagnostic value of the apparent diffusion coefficient (ADC), measured by diffusion-weighted magnetic resonance imaging (MRI), for the diagnosis of breast lesions presenting as mass and non-mass-like enhancement (NMLE). The breast MRI studies of 174 patients were reviewed retrospectively. A total of 188 histologically confirmed lesions were analyzed and classified into 127 mass enhancement (86 malignant and 41 benign) and 61 NMLE (42 malignant and 19 benign). The ADC values were measured using a spin-echo echo-planner-imaging (SE-EPI) sequence with b=1,000 s/mm(2). Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. The mean ADC was 0.99 ± 0.22 × 10(-3)mm(2)/s for invasive cancer, 1.23 ± 0.33 × 10(-3)mm(2)/s for ductal carcinoma in situ (DCIS), and 1.52 ± 0.35 × 10(-3)mm(2)/s for benign adenosis. The mean ADC of all NMLE lesions was 1.44 ± 0.41 × 10(-3)mm(2)/s, which is higher than the mean ADC of all mass lesions, 1.12 ± 0.33 × 10(-3)mm(2)/s. In the ROC analysis, the optimal cutoff ADC value for differentiating benign from malignant lesions was 1.05 × 10(-3)mm(2)/s for mass lesions and 1.35 × 10(-3)mm(2)/s for NMLE. In conclusion, ADC values can be used for the diagnosis of invasive and DCIS as well as benign tumors. The NMLE lesions tend to have higher ADC values than mass lesions; therefore, the morphological appearance of a lesion needs to be considered when using the ADC value for diagnosis.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico , Adenoma/diagnóstico , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Imagem de Difusão por Ressonância Magnética , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Curva ROC , Estudos Retrospectivos
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(3): 305-10, 2013 Jun.
Artigo em Zh | MEDLINE | ID: mdl-23827069

RESUMO

OBJECTIVE: To explore the value of phase ordering with automatic window selection(PAWS)and simultaneous multiple volume(SMV)algorithm double respiratory navigator-gated two-dimensional(2DNAV)dual inversion recovery(DIR)fast spin echo(FSE)high-resolution black-blood coronary artery wall magnetic resonance imaging(MRI)and evaluate its advantages and limitations. METHODS: PAWS and SMV 2DNAV DIR FSE high-resolution black-blood MRI was performed in 21 healthy volunteers. The images were evaluated qualitatively by using four grades(grade 0can not evaluate;grade 1bad;grade 2good;grade 3perfect). Images defined as grade 0 and grade 1 were excluded and those defined as grade 2 and 3 were evaluated further. Thickness of proximal(or middle)segment of right coronary artery(RCA)and left anterior descending branch(LAD)were measured. The difference of wall thickness was analyzed by using two-tailed independent sample t-test. P values of less than 0.05 were considered statistically significant. RESULTS: Among the 38 slice images,31 slices(RCA13 slices,LAD18 slices;grade 214 slices,grade 317 slices)were obtained for further evaluation. The mean thickness of RCA and LAD was(0.94±0.16)and(0.89±0.15)mm,respectively,and the difference was not significant(t=-0.790,P>0.05). CONCLUSION: PAWS and SMV algorithm 2DNAV DIR FSE high-resolution black-blood MRI has certain clinical value for coronary artery wall imaging.


Assuntos
Vasos Coronários/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Ann Transl Med ; 11(9): 323, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37405001

RESUMO

Background: Five-year treatment with tamoxifen (TAM) has been the traditional standard of care for breast cancer. Organising pneumonia (OP) is a rare but significant complication of radiation therapy for breast cancer. The effect of TAM leading to OP has not yet been clearly documented. Case Description: This report describes the case of a 38-year-old female who developed progressive aggravation of round-like patchy bilateral pulmonary infiltrated with a reverse halo sign but without any clinical symptoms 5 months after TAM therapy, following breast-conserving surgery and radiotherapy (RT) for breast carcinoma. A lung biopsy was performed and revealed a histological pattern of OP. TAM therapy was discontinued, and subsequent gradual radiological improvement was observed. As there was no proof for TAM had caused the incident, TAM was re-administrated. Eight months after reinstitution of TAM, the same patchy migratory bilateral pulmonary infiltrated with reverse halo sign was found on chest CT with the patient claiming no discomforts nor any clinical symptoms. The diagnosis of TAM-related OP was made based on the exclusion of other causes and recurrence with the re-administration of TAM. The multidisciplinary team (MDT) concluded that TAM should be withdrawn and a "wait-and-see" approach was taken after a comprehensive assessment, instead of altering the medication or performing prophylactic mastectomy. Conclusions: The withdrawal and rechallenge of TAM strongly suggest that it may play a role as a cofactor in the occurrence of OP after RT for breast cancer, and RT may also be a cofactor in the occurrence of OP. It is extremely important to be alerted to the possibility of OP after concurrent or sequential hormonal therapy and RT.

8.
Int J Cardiovasc Imaging ; 39(9): 1741-1752, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37316646

RESUMO

This study aimed to construct a large animal model of coronary microvascular embolism, and investigate whether it could mimic the clinical imaging phenotypes of myocardial hypoperfusion in patients with ST-segment elevation myocardial infarction (STEMI). Nine minipigs underwent percutaneous coronary embolization with microspheres, followed by cardiac magnetic resonance (CMR) on week 1, 2 and 4 post operation. Microvascular obstruction (MVO) was defined as the isolated hypointense core within the enhanced area on late gadolinium enhancement images, which evolved during a 4-week follow-up. Fibrotic fraction of the segments was measured by Masson trichrome staining using a panoramic analysis software. Iron deposit and macrophage infiltration were quantified based on Perl's blue and anti-CD163 staining, respectively. Seven out of 9 (77.8%) minipigs survived and completed all of the imaging follow-ups. Four out of 7 (57.1%) minipigs were identified as transmural infarct with MVO. The systolic wall thickening (SWT) of MVO zone was similar to that of infarct zone (P = 0.762). Histopathology revealed transmural deposition of collagen, with microvessels obstructed by microspheres. The fibrotic fraction of infarct with MVO segments was similar to that of infarct without MVO segments (P = 0.954). The fraction of iron deposit in infarct with MVO segments was higher than that of infarct without MVO segments (P < 0.05), but the fraction of macrophage infiltration between these two segments did not show statistical difference (P = 0.723). Large animal model of coronary microvascular embolism could mimic most clinical imaging phenotypes of myocardial hypoperfusion in patients with STEMI, demonstrated by serial CMR and histopathology.


Assuntos
Doença da Artéria Coronariana , Embolia , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Animais , Suínos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Meios de Contraste , Porco Miniatura , Circulação Coronária , Valor Preditivo dos Testes , Gadolínio , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Modelos Animais , Embolia/diagnóstico por imagem , Embolia/etiologia , Microcirculação
9.
Quant Imaging Med Surg ; 13(12): 8350-8357, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38106260

RESUMO

Background: Background parenchymal enhancement (BPE) is defined as the enhanced proportion of normal fibroglandular tissue on enhanced magnetic resonance imaging. BPE shows promise as a quantitative imaging biomarker (QIB). However, the lack of consensus among radiologists in their semi-quantitative grading of BPE limits its clinical utility. Methods: The main objective of this study was to develop a BPE quantification model according to clinical expertise, with the BPE integral being used as a QIB to incorporate both the volume and intensity of the enhancement metrics. The model was applied to 2,786 cases to compare our quantitative results with radiologists' semi-quantitative BPE grading to evaluate the effectiveness of using the BPE integral as a QIB for analyzing BPE. Comparisons between multiple groups of nonnormally distributed BPE integrals were performed using the Kruskal-Wallis test. Results: Our study found a considerable degree of concordance between our BPE quantitative integral and radiologists' semi-quantitative assessments. Specifically, our research results revealed significant variability in BPE integral attained through the BPE quantification framework among all semi-quantitative BPE grading groups labeled by experienced radiologists, including mild-moderate (P<0.001), mild-marked (P<0.001), and moderate-marked (P<0.001). Furthermore, there was an apparent correlation between BPE integral and BPE grades, with marked BPE displaying the highest BPE integral, followed by moderate BPE, with mild BPE exhibiting the lowest BPE integral value. Conclusions: The study developed and implemented a BPE quantification framework, which incorporated both the volume and intensity of enhancement and which could serve as a QIB for BPE.

10.
Radiology ; 262(1): 269-78, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22056688

RESUMO

PURPOSE: To assess quantitative susceptibility mapping (QSM) for reducing the inconsistency of standard magnetic resonance (MR) imaging sequences in measurements of cerebral microbleed burden. MATERIALS AND METHODS: This retrospective study was HIPAA compliant and institutional review board approved. Ten patients (5.6%) were selected from among 178 consecutive patients suspected of having experienced a stroke who were imaged with a multiecho gradient-echo sequence at 3.0 T and who had cerebral microbleeds on T2*-weighted images. QSM was performed for various ranges of echo time by using both the magnitude and phase components in the morphology-enabled dipole inversion method. Cerebral microbleed size was measured by two neuroradiologists on QSM images, T2*-weighted images, susceptibility-weighted (SW) images, and R2* maps calculated by using different echo times. The sum of susceptibility over a region containing a cerebral microbleed was also estimated on QSM images as its total susceptibility. Measurement differences were assessed by using the Student t test and the F test; P < .05 was considered to indicate a statistically significant difference. RESULTS: When echo time was increased from approximately 20 to 40 msec, the measured cerebral microbleed volume increased by mean factors of 1.49 ± 0.86 (standard deviation), 1.64 ± 0.84, 2.30 ± 1.20, and 2.30 ± 1.19 for QSM, R2*, T2*-weighted, and SW images, respectively (P < .01). However, the measured total susceptibility with QSM did not show significant change over echo time (P = .31), and the variation was significantly smaller than any of the volume increases (P < .01 for each). CONCLUSION: The total susceptibility of a cerebral microbleed measured by using QSM is a physical property that is independent of echo time.


Assuntos
Hemorragia Cerebral/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Algoritmos , Análise de Variância , Circulação Cerebrovascular , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Estudos Retrospectivos
11.
Quant Imaging Med Surg ; 12(7): 3860-3872, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35782247

RESUMO

Background: The breast imaging reporting and data system (BI-RADS) lexicon provides a standardized terminology for describing leision characteristics but does not provide defined rules for converting specific imaging features into diagnostic categories. The inter-reader agreement of the BI-RADS is moderate. In this study, we explored the use of a simplified protocol and scoring system for BI-RADS categorization which integrates the morphologic features (MF), kinetic time-intensity curve (TIC), and apparent diffusion coefficient (ADC) values with equal weights, with a view to providing a convenient and practical method for breast magnetic resonance imaging (MRI) and improving the inter-reader agreement and diagnostic performance of BI-RADS. Methods: This cross-sectional, retrospective, single-center study included 879 patients with 898 histopathologically verified lesions who underwent an MRI scan on a 3.0 Tesla GE Discovery 750 MRI scanner between January 1, 2017, and June 30, 2020. The BI-RADS categorization of the studied lesions was assessed according to the sum of the assigned scores (the presence of malignant MF, lower ADC, and suspicious TIC each warranted a score of +1). Total scores of +2 and +3 were classified as category 5, scores of +1 were classified as category 4, and scores of +0 but with other lesions of interest were classified as category 3. The receiver operating characteristic (ROC) curves were plotted, and the sensitivity, specificity, and accuracy of this categorization were investigated to assess its efficacy and its consistency with pathology. Results: There were 472 malignant, 104 risk, and 322 benign lesions. Our simplified scoring protocol had high diagnostic accuracy, with an area under curve (AUC) value of 0.896. In terms of the borderline effect of pathological risk and category 4 lesions, our results showed that when risk lesions were classified together with malignant ones, the AUC value improved (0.876 vs. 0.844 and 0.909 vs. 0.900). When category 4 and 5 lesions were classified as malignant, the specificity, accuracy, and AUC value decreased (82.3% vs. 93.2%, 89.3% vs. 90.2%, and 0.876 vs. 0.909, respectively). Therefore, to improve the diagnostic accuracy of the protocol for BI-RADS categorization, only category 5 lesions should be considered to be malignant. Conclusions: Our simplified scoring protocol that integrates MF, TIC, and ADC values with equal weights for BI-RADS categorization could improve both the diagnostic performance of the protocol for BI-RADS categorization in clinical practice and the understanding of the benign-risk-malignant breast diseases.

12.
Cardiovasc Diagn Ther ; 12(1): 103-113, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35282666

RESUMO

Background: To analyze the relationship between left ventricular (LV) myocardial strain and transmurality of myocardial infarction at three circular sections (basal, mid-ventricular, apical) by a combined analysis of cardiac magnetic resonance feature tracking (CMR-FT) and late gadolinium enhancement (LGE) information in a cohort of ST-elevation acute myocardial infarction (STEMI) patients after primary percutaneous coronary intervention (PPCI). Methods: In all, 136 patients with STEMI who underwent PPCI within 12 hours of symptom onset were included. CMR-FT and LGE-MRI were performed 5±2 days after PCI for measuring regional and global myocardial strain indexes and transmural extent. Multivariate regression analysis and Kaplan-Meier survival analysis were performed. Results: Regional radial and circumferential strain decreased with increasing transmurality of myocardial infarction irrespective of basal, mid-ventricular, or apical segments. Segmental longitudinal strain was significantly decreased in the transmural infarcted segments only at the apical and mid-ventricular levels. A significant correlation was found between the number of transmural infarcts and global strain parameters in the apical and mid-ventricular portions. Transmural infarcted segments in apical + mid-ventricular portions >2 was related to an increased risk of cardiac events in patients with STEMI following PPCI than those ≤2. GLS was found to be an independent predictor of cardiac events in these patients. Conclusions: The number of transmural infarcted segments in apical + mid-ventricular portions affects LV global function and prognosis. Global longitudinal strain (GLS) is a significant predictor of adverse events after PPCI for STEMI. Morphologic and functional data fused to study complex pathophysiologic processes of LV early after STEMI may help in risk stratification of patients.

13.
Front Oncol ; 12: 946580, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033449

RESUMO

Importance: The utilization of artificial intelligence for the differentiation of benign and malignant breast lesions in multiparametric MRI (mpMRI) assists radiologists to improve diagnostic performance. Objectives: To develop an automated deep learning model for breast lesion segmentation and characterization and to evaluate the characterization performance of AI models and radiologists. Materials and methods: For lesion segmentation, 2,823 patients were used for the training, validation, and testing of the VNet-based segmentation models, and the average Dice similarity coefficient (DSC) between the manual segmentation by radiologists and the mask generated by VNet was calculated. For lesion characterization, 3,303 female patients with 3,607 pathologically confirmed lesions (2,213 malignant and 1,394 benign lesions) were used for the three ResNet-based characterization models (two single-input and one multi-input models). Histopathology was used as the diagnostic criterion standard to assess the characterization performance of the AI models and the BI-RADS categorized by the radiologists, in terms of sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC). An additional 123 patients with 136 lesions (81 malignant and 55 benign lesions) from another institution were available for external testing. Results: Of the 5,811 patients included in the study, the mean age was 46.14 (range 11-89) years. In the segmentation task, a DSC of 0.860 was obtained between the VNet-generated mask and manual segmentation by radiologists. In the characterization task, the AUCs of the multi-input and the other two single-input models were 0.927, 0.821, and 0.795, respectively. Compared to the single-input DWI or DCE model, the multi-input DCE and DWI model obtained a significant increase in sensitivity, specificity, and accuracy (0.831 vs. 0.772/0.776, 0.874 vs. 0.630/0.709, 0.846 vs. 0.721/0.752). Furthermore, the specificity of the multi-input model was higher than that of the radiologists, whether using BI-RADS category 3 or 4 as a cutoff point (0.874 vs. 0.404/0.841), and the accuracy was intermediate between the two assessment methods (0.846 vs. 0.773/0.882). For the external testing, the performance of the three models remained robust with AUCs of 0.812, 0.831, and 0.885, respectively. Conclusions: Combining DCE with DWI was superior to applying a single sequence for breast lesion characterization. The deep learning computer-aided diagnosis (CADx) model we developed significantly improved specificity and achieved comparable accuracy to the radiologists with promise for clinical application to provide preliminary diagnoses.

14.
J Am Heart Assoc ; 11(18): e026232, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36073634

RESUMO

Background Nicorandil was reported to improve microvascular dysfunction and reduce reperfusion injury when administered before primary percutaneous coronary intervention. In this multicenter, prospective, randomized, double-blind clinical trial (CHANGE [Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention]), we investigated the effects of nicorandil administration on infarct size in patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods and Results A total of 238 patients with ST-segment-elevation myocardial infarction were randomized to receive intravenous nicorandil (n=120) or placebo (n=118) before reperfusion. Patients in the nicorandil group received a 6-mg intravenous bolus of nicorandil followed by continuous infusion at a rate of 6 mg/h. Patients in the placebo group received the same dose of placebo. The predefined primary end point was infarct size on cardiac magnetic resonance (CMR) imaging performed at 5 to 7 days and 6 months after reperfusion. CMR imaging was performed in 201 patients (84%). Infarct size on CMR imaging at 5 to 7 days after reperfusion was significantly smaller in the nicorandil group compared with the placebo (control) group (26.5±17.1 g versus 32.4±19.3 g; P=0.022), and the effect remained significant on long-term CMR imaging at 6 months after reperfusion (19.5±14.4 g versus 25.7±15.4 g; P=0.008). The incidence of no-reflow/slow-flow phenomenon during primary percutaneous coronary intervention was much lower in the nicorandil group (9.2% [11/120] versus 26.3% [31/118]; P=0.001), and thus, complete ST-segment resolution was more frequently observed in the nicorandil group (90.8% [109/120] versus 78.0% [92/118]; P=0.006). Left ventricular ejection fraction on CMR imaging was significantly higher in the nicorandil group than in the placebo group at both 5 to 7 days (47.0±10.2% versus 43.3±10.0%; P=0.011) and 6 months (50.1±9.7% versus 46.4±8.5%; P=0.009) after reperfusion. Conclusions In the present trial, administration of nicorandil before primary percutaneous coronary intervention led to improved myocardial perfusion grade, increased left ventricular ejection fraction, and reduced myocardial infarct size in patients with ST-segment-elevation myocardial infarction. Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03445728.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Nicorandil/uso terapêutico , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
15.
Cardiovasc Drugs Ther ; 25(3): 259-65, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21626218

RESUMO

PURPOSE: Experimental and epidemiological studies suggest that omega-3 fatty acids have an antiarrhythmic effect. However, evidence from randomized controlled trials (RCTs) for prevention of sudden cardiac death (SCD) remains controversial. This study sought to evaluate the efficacy of omega-3 fatty acids for secondary prevention of SCD in patients with cardiovascular disease (CVD) in the era of guidelines-based therapy. METHODS: We conducted a PubMed/EMBASE/CENTRAL search for RCTs evaluating omega-3 fatty acids for CVD secondary prevention with at least 6 months follow-up and with data on SCD. Primary outcome was SCD. Secondary outcomes were cardiovascular mortality and all-cause mortality. RESULTS: Ten randomized controlled trials were identified evaluating a total of 33,429 patients with CVD. In patients with guidelines-adjusted therapy, omega-3 fatty acids did not reduce the risk ratio (RR) of SCD (RR:0.96; 95% CI: 0.84-1.10). In patients with non- guidelines-adjusted therapy, omega-3 fatty acids reduced the RR of SCD (RR: 0.64; 95% CI: 0.51-0.80). Overall, RR for cardiac death and all-cause mortality were 0.81 (95% CI: 0.69-0.95) and 0.89 (95% CI: 0.79-1.01), respectively. CONCLUSIONS: In the era of guidelines-adjusted treatment for CVD secondary prevention, omega-3 fatty acids do not appear to reduce SCD.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Morte Súbita Cardíaca/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Doenças Cardiovasculares/complicações , Morte Súbita Cardíaca/etiologia , Ácidos Graxos Ômega-3/administração & dosagem , Seguimentos , Humanos , Razão de Chances , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Prevenção Secundária/métodos
16.
J Clin Hypertens (Greenwich) ; 23(2): 218-231, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33369066

RESUMO

It is widely recognized that hypertension is one of the major risk factor for disease severity and mortality in patients with coronavirus disease 2019 (COVID-19). However, type 2 diabetes mellitus (T2DM) and hypertension are frequent comorbid conditions, complicating the assessment of hypertension's individual contribution to the risk. The aims of this study were to evaluate the contributions of hypertension alone, T2DM alone, or their combination to the risk of death, acute respiratory distress syndrome (ARDS)/respiratory failure, and severe COVID-19 infection. Additionally, we assessed risks associated with elevated blood pressure and fasting blood glucose on the same three clinical outcomes. Multivariate logistic models were used for these analyses. Among the 3400 patients, 3327(97.9%) survived and 73(2.1%) died. Compared to patients having neither hypertension nor T2DM (n = 1392), the risk of mortality was significantly higher in patients with T2DM alone (n = 226, OR 5.26 [95% CI: 2.39-11.58]) or with T2DM in combination with hypertension (n = 507, OR 3.02, [95% CI: 1.48-6.15]). Similarly, T2DM was a risk factor for development of ARDS/respiratory failure and severe infection. Hypertension alone (n = 1275) only conferred additional risk for the development of severe infection (OR 1.22 [95% CI: 1.00-1.51]). In conclusion, neither hypertension nor elevated blood pressure was independent risk factors for death or ARDS/respiratory failure but hypertension marginally increased the risk of severe COVID-19 infection. The risk associated with hypertension is accentuated through its confounding effect on T2DM.


Assuntos
COVID-19/mortalidade , Diabetes Mellitus Tipo 2/complicações , Hipertensão/complicações , Síndrome do Desconforto Respiratório/mortalidade , Adulto , Idoso , Glicemia/análise , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/virologia , Estudos de Casos e Controles , China/epidemiologia , Comorbidade , Diabetes Mellitus Tipo 2/diagnóstico , Jejum/sangue , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/etiologia , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/genética , Índice de Gravidade de Doença
17.
Sci Rep ; 11(1): 4145, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603047

RESUMO

The pandemic of Coronavirus Disease 2019 (COVID-19) is causing enormous loss of life globally. Prompt case identification is critical. The reference method is the real-time reverse transcription PCR (RT-PCR) assay, whose limitations may curb its prompt large-scale application. COVID-19 manifests with chest computed tomography (CT) abnormalities, some even before the onset of symptoms. We tested the hypothesis that the application of deep learning (DL) to 3D CT images could help identify COVID-19 infections. Using data from 920 COVID-19 and 1,073 non-COVID-19 pneumonia patients, we developed a modified DenseNet-264 model, COVIDNet, to classify CT images to either class. When tested on an independent set of 233 COVID-19 and 289 non-COVID-19 pneumonia patients, COVIDNet achieved an accuracy rate of 94.3% and an area under the curve of 0.98. As of March 23, 2020, the COVIDNet system had been used 11,966 times with a sensitivity of 91.12% and a specificity of 88.50% in six hospitals with PCR confirmation. Application of DL to CT images may improve both efficiency and capacity of case detection and long-term surveillance.


Assuntos
COVID-19/diagnóstico por imagem , COVID-19/diagnóstico , Tomografia Computadorizada por Raios X/métodos , COVID-19/epidemiologia , COVID-19/metabolismo , China/epidemiologia , Confiabilidade dos Dados , Aprendizado Profundo , Humanos , Pulmão/patologia , Pneumonia/diagnóstico por imagem , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
18.
Radiology ; 257(1): 135-43, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20713607

RESUMO

PURPOSE: To assess the usefulness of apparent diffusion coefficients (ADCs) for characterizing renal cell carcinoma (RCC) subtypes at 3.0 T. MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study, and informed consent was waived. Eighty-three patients underwent diffusion-weighted (DW) magnetic resonance (MR) imaging of 85 renal masses. In each patient, precontrast single-shot spin-echo echo-planar DW imaging was performed with b values of 0 and 500 and 0 and 800 sec/mm(2) by using a 3.0-T MR imaging system. Differences in ADCs between the RCC lesions and uninvolved renal parenchyma were tested by using a paired-samples t test. One-way analysis of variance was used to compare ADCs of the various RCC subtypes. Receiver operating characteristic (ROC) curve analysis was used to test the ability of ADCs in differentiating clear cell from non-clear cell RCCs. RESULTS: Pathologic diagnoses of the 85 tumors (median diameter, 4.4 cm) in the 83 patients (54 men, 29 women; age range, 23-75 years; mean age, 49.4 years) were clear cell RCC for 49 tumors, papillary RCC for 22 tumors, and chromophobic RCC for 14 tumors. With b values of 0 and 500 sec/mm(2), clear cell RCCs showed a significantly higher mean ADC (1.849 × 10(-3) mm(2)/sec) than papillary (1.087 × 10(-3) mm(2)/sec) and chromophobic (1.307 × 10(-3) mm(2)/sec) RCCs (P < .001); however, the difference between papillary and chromophobic RCCs was not significant (P = .068). With b values of 0 and 800 sec/mm(2), clear cell RCC showed the largest mean ADC (1.698 × 10(-3) mm(2)/sec) of the three subtypes, and the difference between each pair of subtypes was significant (P < .001). ADCs obtained with b values of 0 and 800 sec/mm(2) were more effective for distinguishing clear cell from non-clear cell RCC (area under the ROC curve, 0.973): A threshold value of 1.281 × 10(-3) mm(2)/sec permitted distinction with high sensitivity (95.9%) and specificity (94.4%). CONCLUSION: DW imaging with b values of 0 and 800 sec/mm(2) allows sensitive and specific differentiation of clear cell, papillary, and chromophobic RCCs, suggesting that DW imaging may be useful in the preoperative characterization of RCC.


Assuntos
Carcinoma de Células Renais/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Renais/patologia , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Heart Surg Forum ; 12(4): E225-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19683994

RESUMO

BACKGROUND: The 3-dimensional arrangement of the ventricular mass has been controversial. The aim of the present study was to investigate the macroarchitecture of ventricular myocardial fibers and to analyze whether it is consistent with the helical ventricular myocardial band (HVMB) hypothesis. METHODS: Eight excised human hearts were scanned by diffusion tensor magnetic resonance imaging (DT-MRI). Fiber tracking was then used with the DT-MRI data to reconstruct and visualize the positions of the myocardial fibers to reveal the architecture of ventricular myocardial fibers. RESULTS: The left ventricular myocardial fibers were found to consist of 2 crossed populations that were approximately normal from the epicardium to the endocardium in the tangent plane. The myocardial fibers in the middle of the myocardium had a smooth, linear angular rotation. The ventricular myocardial fibers maintained complete continuity and specific orientations that corresponded to the HVMB structure. CONCLUSIONS: The architecture of the ventricular myocardial fibers in the human heart conforms to the HVMB structural hypothesis.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Ventrículos do Coração/citologia , Modelos Anatômicos , Modelos Cardiovasculares , Miócitos Cardíacos/citologia , Humanos , Técnicas In Vitro
20.
Heart Surg Forum ; 12(2): E85-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19383593

RESUMO

OBJECTIVE: The 3-dimensional arrangement of the ventricular mass remains controversial. In this study, we used magnetic resonance diffusion tensor imaging (MRDTI) in an attempt to determine whether the ventricular mass is arranged in the form of a helical ventricular myocardial band (HVMB) and what the geometrical features of the HVMB are in postmortem pig hearts. MATERIALS AND METHODS: Ten pig hearts were harvested from the slaughterhouse, and their whole-body MR images were obtained. The data were obtained via DTI by single-shot echo planar imaging and sensitivity encoding. The pig hearts were scanned with single-shot echo planar imaging and sensitivity-encoding scans (TE/TRZ78.5/10000 ms) with diffusion-sensitized gradients (b = 800 s/mm2) along 6 directions. Color-coded imaging and fiber-tracking techniques were used to investigate the arrangement of the fibers of ventricular mass on a GE Healthcare Advantage Workstation (Microsoft Windows). RESULTS: Color-coded images showed that the ventricular wall in each section was uniformly divided into 3 layers (subendocardial, middle, and subepicardial) in all samples. Fiber tracking showed that the subendocardial layer ran obliquely from base to apex, turned a circle, and transformed into the middle layer at the apex, and then ran obliquely upward. The ventricular mass was arranged in the form of double-helical coils. The crossing angle between subendocardial layer and middle layer was nearly vertical. CONCLUSION: Results of our investigation with MRDTI support the theory of Torrent-Guasp et al that the ventricular mass is arranged in the form of an HVMB.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Ventrículos do Coração/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Função Ventricular/fisiologia , Animais , Técnicas In Vitro , Tamanho do Órgão , Suínos
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