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1.
J Acad Nutr Diet ; 115(3): 353-359, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25300225

RESUMO

BACKGROUND: Breast density is an established predictor of breast cancer risk, and there is considerable interest in associations of modifiable lifestyle factors, such as diet, with breast density. OBJECTIVE: To determine whether dietary energy density (ED) is associated with percent dense breast volume (%DBV) and absolute dense breast volume (ADBV) in young women. DESIGN: A cross-sectional analysis was conducted with women who participated in the Dietary Intervention Study in Children Follow-Up Study. %DBV and ADBV were measured by magnetic resonance imaging. Diet was assessed by three 24-hour recalls. Dietary ED (kilocalories/gram) was calculated using three methods: food only, food and caloric beverages, and food and all beverages. PARTICIPANTS/SETTING: One hundred seventy-two women (aged 25 to 29 years) who were enrolled in the Dietary Intervention Study in Children Follow-Up Study. Participants who reported breast augmentation or reduction surgery or were pregnant or lactating within 3 months before breast density assessment were excluded. MAIN OUTCOME MEASURES: ADBV and %DBV. STATISTICAL ANALYSES PERFORMED: Multivariable linear mixed effects models were used. Final models were adjusted for race, smoking status, education, parity, duration of sex hormone use, whole body percent fat, childhood body mass index z score, and energy from beverages. RESULTS: After adjustment, each 1 kcal/g unit increase in food-only ED was associated with a 25.9% (95% CI 6.2% to 56.8%) increase in %DBV (P=0.01). Childhood body mass index z score modified the association between food-only ED and %DBV such that a significant positive association was observed only in women who were heavier as children. Food-only ED was not associated with ADBV in all women, but a borderline significant positive association was observed in women who had higher childhood body mass index z scores. CONCLUSIONS: This is the first report to suggest a potential role for dietary ED in breast density; the effects of long-term exposure to high-ED diets on breast cancer risk remain unknown.


Assuntos
Mama/anatomia & histologia , Dieta/métodos , Ingestão de Energia/fisiologia , Comportamento Alimentar/fisiologia , Absorciometria de Fóton , Adiposidade/fisiologia , Adulto , Composição Corporal/fisiologia , Índice de Massa Corporal , Mama/ultraestrutura , Estudos Transversais , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Análise Multivariada
2.
Magn Reson Imaging ; 29(9): 1215-21, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21920686

RESUMO

Promising recent investigations have shown that breast malignancies exhibit restricted diffusion on diffusion-weighted imaging (DWI) and may be distinguished from normal tissue and benign lesions in the breast based on differences in apparent diffusion coefficient (ADC) values. In this study, we assessed the influence of intravoxel fat signal on breast diffusion measures by comparing ADC values obtained using a diffusion-weighted single shot fast spin-echo sequence with and without fat suppression. The influence of breast density on ADC measures was also evaluated. ADC values were calculated for both tumor and normal fibroglandular tissue in a group of 21 women with diagnosed breast cancer. There were systematic underestimations of ADC for both tumor and normal breast tissue due to intravoxel contribution from fat signal on non-fat-suppressed DWI. This ADC underestimation was more pronounced for normal tissue values (mean difference=40%) than for tumors (mean difference=27%, P<.001) and was worse in women with low breast tissue density vs. those with extremely dense breasts (P<.05 for both tumor and normal tissue). Tumor conspicuity measured by contrast-to-noise ratio was significantly higher on ADC maps created with fat suppression and was not significantly associated with breast density. In summary, robust fat suppression is important for accurate breast ADC measures and optimal lesion conspicuity on DWI.


Assuntos
Tecido Adiposo/patologia , Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia , Neoplasias da Mama/patologia , Meios de Contraste/farmacologia , Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Mamografia/métodos , Pessoa de Meia-Idade , Modelos Estatísticos , Imagens de Fantasmas
3.
J Arthroplasty ; 23(6): 833-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18534519

RESUMO

There are currently no ideal quantitative measures assessing osteolysis after total joint arthroplasty. This study reports a new approach for quantification of osteolytic lesions on radiographs of total hip arthroplasty with the hypothesis that computer-assisted lesion quantification improves analysis precision over currently used qualitative visual assessment and thus improves progression monitoring. Duplicate exposure sets of anterior-posterior and frog-leg view radiographs of 15 volunteer total hip arthroplasty patients with radiographically evident periprosthetic lucencies were used. Two independent readers delineated the lesions using on-screen digital marker tools. Based on duplicate readings of the first exposure set only, intraoperator precision had a coefficient of variation (CV) from 1.5% to 3.4%, whereas interoperator precision CV ranged from 3.2% to 4.6%. The reproducibility of the x-ray technique as assessed by single readings of both sets of x-rays was CV 3.2% to 4.8%. The new technique compares favorably to precision of qualitative visual assessment and permits more accurate detection and quantitation of osteolytic lesions.


Assuntos
Artroplastia de Quadril/efeitos adversos , Fêmur/diagnóstico por imagem , Fêmur/patologia , Processamento de Imagem Assistida por Computador/métodos , Osteólise/diagnóstico por imagem , Osteólise/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico por Computador/métodos , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiografia , Reprodutibilidade dos Testes
4.
J Magn Reson Imaging ; 25(1): 82-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17173311

RESUMO

PURPOSE: To determine whether combining 3D fast imaging employing steady-state acquisition (FIESTA) and T1-weighted contrast-enhanced (CE) sequences could help characterize lesions in 32 women with benign, in situ, or invasive breast lesions. Since FIESTA provides both T1 and T2 information on the same three-dimensional (3D) matrix as high-resolution T1-weighted dynamic data, we aimed to verify whether invasive lesions could be separated from in situ and/or benign lesions using quantitative FIESTA measures of tissue intensity and homogeneity. MATERIAL AND METHODS: With the use of CE-MRI data, regions of interest (ROIs) were manually delineated in enhancing lesions and on surrounding normal tissue. These ROIs were then applied to 3D FIESTA data. Quantitative measures between lesion and normal tissue were compared among the lesion groups. RESULTS: On FIESTA most invasive cancer lesions were hypointense compared to surrounding normal tissue (mean lesion intensity was 89% of normal tissue intensity), whereas most ductal and benign lesions appeared hyperintense compared to surrounding normal tissue (lesions at 100.9% and 121.9% of normal tissue intensity, respectively). Measures obtained from resampled T2-weighted data showed no significant differences between the invasive and benign lesion groups. CONCLUSION: We detected significant differences between invasive and noninvasive lesions by quantifying intensity differences between the lesions and surrounding normal tissue on FIESTA.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias da Mama/patologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica
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