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1.
Nutr Cancer ; 71(8): 1276-1282, 2019.
Article in English | MEDLINE | ID: mdl-31025887

ABSTRACT

Background: Anthropometric indices have a debatable relationship with breast cancer (BC) among different ethnicity. In the current study, we have evaluated the relationship between anthropometric indices and BC in Iranian participants. Methods: Between 2012 and 2014, a total of 7,805 women were enrolled from different mammography centers in Isfahan province, Iran. For each participant, a detailed questionnaire was filled out and anthropometric indices were measured by trained technicians. We used logistic regression models to estimate odds ratios (OR) and 95% confidence interval (CI) for BC risk associated with anthropometry measurements, stratified on menopausal status. Results: In the postmenopausal group, weight ≥68 kg compared to weight <61.75 kg was associated with decreased risk of BC (OR = 0.78; 95% CI: 0.63-0.97). Postmenopausal women with Waist-Hip Ratio (WHR) ≥ 0.85 compared to WHR < 0.77 were at increased risk of BC (OR = 1.36; 95% CI: 1.07-1.73). Both premenopausal and postmenopausal women had a decreased risk of BC with higher Obesity Index (OI) and Relative Weight. Conclusion: Ethnicity appears to play an important role in the discrepancies between results of different studies about the correlation of anthropometric features with BC.


Subject(s)
Anthropometry/methods , Body Mass Index , Body Weight/physiology , Breast Neoplasms/etiology , Obesity/complications , Waist Circumference , Waist-Hip Ratio , Adult , Breast Neoplasms/pathology , Female , Humans , Iran , Middle Aged , Odds Ratio , Postmenopause , Premenopause , Retrospective Studies , Risk Factors
2.
Cureus ; 10(6): e2895, 2018 Jun 29.
Article in English | MEDLINE | ID: mdl-30175001

ABSTRACT

Transarterial radioembolization using yttrium-90 microspheres is an established and effective treatment for liver malignancies. Determining response to this treatment is difficult due to the radical changes that occur in tissue as a response to radiation. Though accurate assessment of treatment response is paramount for proper patient disposition, there is currently no standardized assessment protocol. Current methods of assessment often consider changes in size, necrosis, vascularity, fluorodeoxyglucose-positron emission tomography FDG-PET metabolic activity, and diffusion using diffusion-weighted magnetic resonance imaging (DWI). Current methods of assessment require a lag time of one to two months post-treatment to determine treatment effectiveness. This delay is a hindrance to obtaining better patient outcomes, giving rise to a need to identify markers for faster determination of treatment efficacy.

3.
Abdom Radiol (NY) ; 43(12): 3307-3316, 2018 12.
Article in English | MEDLINE | ID: mdl-29700590

ABSTRACT

PURPOSE: To evaluate precision of a software-based liver surface nodularity (LSN) score derived from CT images. METHODS: An anthropomorphic CT phantom was constructed with simulated liver containing smooth and nodular segments at the surface and simulated visceral and subcutaneous fat components. The phantom was scanned multiple times on a single CT scanner with adjustment of image acquisition and reconstruction parameters (N = 34) and on 22 different CT scanners from 4 manufacturers at 12 imaging centers. LSN scores were obtained using a software-based method. Repeatability and reproducibility were evaluated by intraclass correlation (ICC) and coefficient of variation. Using abdominal CT images from 68 patients with various stages of chronic liver disease, inter-observer agreement and test-retest repeatability among 12 readers assessing LSN by software- vs. visual-based scoring methods were evaluated by ICC. RESULTS: There was excellent repeatability of LSN scores (ICC:0.79-0.99) using the CT phantom and routine image acquisition and reconstruction parameters (kVp 100-140, mA 200-400, and auto-mA, section thickness 1.25-5.0 mm, field of view 35-50 cm, and smooth or standard kernels). There was excellent reproducibility (smooth ICC: 0.97; 95% CI 0.95, 0.99; CV: 7%; nodular ICC: 0.94; 95% CI 0.89, 0.97; CV: 8%) for LSN scores derived from CT images from 22 different scanners. Inter-observer agreement for the software-based LSN scoring method was excellent (ICC: 0.84; 95% CI 0.79, 0.88; CV: 28%) vs. good for the visual-based method (ICC: 0.61; 95% CI 0.51, 0.69; CV: 43%). Test-retest repeatability for the software-based LSN scoring method was excellent (ICC: 0.82; 95% CI 0.79, 0.84; CV: 12%). CONCLUSION: The software-based LSN score is a quantitative CT imaging biomarker with excellent repeatability, reproducibility, inter-observer agreement, and test-retest repeatability.


Subject(s)
Image Processing, Computer-Assisted/methods , Liver/diagnostic imaging , Phantoms, Imaging , Tomography, X-Ray Computed/methods , Observer Variation , Reproducibility of Results
4.
Abdom Radiol (NY) ; 42(4): 1189-1198, 2017 04.
Article in English | MEDLINE | ID: mdl-28028556

ABSTRACT

PURPOSE: The aim of the study was to determine in patients undergoing gadoxetate disodium (Gx)-enhanced MR exams whether proton density fat fraction (PDFF) estimation accuracy of magnitude-based multi-gradient-echo MRI (MRI-M) could be improved by using high flip angle (FA) on post-contrast images. MATERIALS AND METHODS: Thirty-one adults with known or suspected hepatic steatosis undergoing 3T clinical Gx-enhanced liver MRI were enrolled prospectively. MR spectroscopy (MRS), the reference standard, was performed before Gx to measure MRS-PDFF. Low (10°)- and high (50°)-flip angle (FA) MRI-M sequences were acquired before and during the hepatobiliary phase after Gx administration; MRI-PDFF was estimated in the MRS-PDFF voxel location. Linear regression parameters (slope, intercept, average bias, R 2) were calculated for MRS-PDFF as a function of MRI-PDFF for each MRI-M sequence (pre-Gx low-FA, pre-Gx high-FA, post-Gx low-FA, post-Gx high-FA) for all patients and for patients with MRS-PDFF <10%. Regression parameters were compared (Bonferroni-adjusted bootstrap-based tests). RESULTS: Three of the four MRI-M sequences (pre-Gx low-FA, post-Gx low-FA, post-Gx high-FA) provided relatively unbiased PDFF estimates overall and in the low-PDFF range, with regression slopes close to 1 and intercepts and biases close to zero. Pre-Gx high-FA MRI overestimated PDFF in proportion to MRS-PDFF, with slopes of 0.72 (overall) and 0.63 (low-PDFF range). Based on regression bias closest to 0, the post-Gx high-FA sequence was the most accurate overall and in the low-PDFF range. This sequence provided statistically significant improvements in at least two regression parameters compared to every other sequence. CONCLUSION: In patients undergoing Gx-enhanced MR exams, PDFF estimation accuracy of MRI-M can be improved by using high-FA on post-contrast images.


Subject(s)
Contrast Media/administration & dosage , Fatty Liver/diagnostic imaging , Gadolinium DTPA/administration & dosage , Magnetic Resonance Imaging/methods , Adult , Aged , Female , Humans , Image Enhancement/methods , Male , Middle Aged , Prospective Studies , Protons
5.
Radiology ; 283(3): 711-722, 2017 06.
Article in English | MEDLINE | ID: mdl-27809664

ABSTRACT

Purpose To determine whether use of the liver surface nodularity (LSN) score, a quantitative biomarker derived from routine computed tomographic (CT) images, allows prediction of cirrhosis decompensation and death. Materials and Methods For this institutional review board-approved HIPAA-compliant retrospective study, adult patients with cirrhosis and Model for End-Stage Liver Disease (MELD) score within 3 months of initial liver CT imaging between January 3, 2006, and May 30, 2012, were identified from electronic medical records (n = 830). The LSN score was measured by using CT images and quantitative software. Competing risk regression was used to determine the association of the LSN score with hepatic decompensation and overall survival. A risk model combining LSN scores (<3 or ≥3) and MELD scores (<10 or ≥10) was created for predicting liver-related events. Results In patients with compensated cirrhosis, 40% (129 of 326) experienced decompensation during a median follow-up period of 4.22 years. After adjustment for competing risks including MELD score, LSN score (hazard ratio, 1.38; 95% confidence interval: 1.06, 1.79) was found to be independently predictive of hepatic decompensation. Median times to decompensation of patients at high (1.76 years, n = 48), intermediate (3.79 years, n = 126), and low (6.14 years, n = 152) risk of hepatic decompensation were significantly different (P < .001). Among the full cohort with compensated or decompensated cirrhosis, 61% (504 of 830) died during the median follow-up period of 2.26 years. After adjustment for competing risks, LSN score (hazard ratio, 1.22; 95% confidence interval: 1.11, 1.33) and MELD score (hazard ratio, 1.08; 95% confidence interval: 1.06, 1.11) were found to be independent predictors of death. Median times to death of patients at high (0.94 years, n = 315), intermediate (2.79 years, n = 312), and low (4.69 years, n = 203) risk were significantly different (P < .001). Conclusion The LSN score derived from routine CT images allows prediction of cirrhosis decompensation and death. ©RSNA, 2016 Online supplemental material is available for this article.


Subject(s)
Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/mortality , Liver/diagnostic imaging , Tomography, X-Ray Computed , Female , Humans , Liver/pathology , Liver Cirrhosis/complications , Liver Cirrhosis/pathology , Male , Middle Aged , Predictive Value of Tests , Prognosis , Retrospective Studies
6.
Radiology ; 280(3): 771-81, 2016 09.
Article in English | MEDLINE | ID: mdl-27089026

ABSTRACT

Purpose To determine the accuracy, reproducibility, and intra- and interobserver agreement of a computer-based quantitative method to measure liver surface nodularity (LSN) from routine computed tomographic (CT) images as a biomarker for detection and evaluation of cirrhosis. Materials and Methods For this institutional review board-approved HIPAA-compliant retrospective study, adult patients with healthy livers (n = 24) or various stages of hepatitis C virus-induced chronic liver disease (n = 70) with routine nonenhanced and portal venous phase contrast agent-enhanced liver CT imaging with thick-section (5.0 mm) and thin-section (1.25-1.50 mm) axial images obtained between January 1, 2006, and March 31, 2011, were identified from the electronic medical records. A computer algorithm was developed to measure LSN and derive a score. LSN scores, splenic volume, and the ratio of left lateral segment (LLS) to total liver volume (TLV) were measured from the same multiphasic liver CT examinations. Accuracy for differentiating cirrhotic from noncirrhotic livers was assessed by area under the receiver operating characteristic curve. Intra- and interobserver agreement was assessed by intraclass correlation coefficient. Results Median LSN scores from nonenhanced thick-section CT images in cirrhotic livers (3.16; 56 livers) were significantly higher than in noncirrhotic livers (2.11; 38 livers; P < .001). LSN scores from the four CT imaging types (94 patients for each type) were very strongly correlated (range of Spearman r, 0.929-0.960). LSN scores from portal venous phase contrast-enhanced thick-section CT images had significantly higher accuracy (area under the receiver operating characteristic curve, 0.929) than splenic volume (area under the receiver operating characteristic curve, 0.835) or LLS-to-TLV ratio measurements (area under the receiver operating characteristic curve, 0.753) for differentiating cirrhotic from noncirrhotic livers (P = .038 and .003, respectively; n = 94). Intra- and interobserver agreements that used nonenhanced thick CT images were very good (intraclass correlation coefficient, 0.963 and 0.899, respectively). Conclusion Quantitative measurement of LSN on routine CT images accurately differentiated cirrhotic from noncirrhotic livers and was highly reproducible. (©) RSNA, 2016 Online supplemental material is available for this article.


Subject(s)
Liver Cirrhosis/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Biomarkers , Contrast Media , Female , Humans , Liver Cirrhosis/pathology , Male , Middle Aged , Reproducibility of Results , Retrospective Studies
7.
J Magn Reson Imaging ; 43(2): 398-406, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26201284

ABSTRACT

PURPOSE: To determine the accuracy and the effect of possible subject-based confounders of magnitude-based magnetic resonance imaging (MRI) for estimating hepatic proton density fat fraction (PDFF) for different numbers of echoes in adults with known or suspected nonalcoholic fatty liver disease, using MR spectroscopy (MRS) as a reference. MATERIALS AND METHODS: In this retrospective analysis of 506 adults, hepatic PDFF was estimated by unenhanced 3.0T MRI, using right-lobe MRS as reference. Regions of interest placed on source images and on six-echo parametric PDFF maps were colocalized to MRS voxel location. Accuracy using different numbers of echoes was assessed by regression and Bland-Altman analysis; slope, intercept, average bias, and R2 were calculated. The effect of age, sex, and body mass index (BMI) on hepatic PDFF accuracy was investigated using multivariate linear regression analyses. RESULTS: MRI closely agreed with MRS for all tested methods. For three- to six-echo methods, slope, regression intercept, average bias, and R2 were 1.01-0.99, 0.11-0.62%, 0.24-0.56%, and 0.981-0.982, respectively. Slope was closest to unity for the five-echo method. The two-echo method was least accurate, underestimating PDFF by an average of 2.93%, compared to an average of 0.23-0.69% for the other methods. Statistically significant but clinically nonmeaningful effects on PDFF error were found for subject BMI (P range: 0.0016 to 0.0783), male sex (P range: 0.015 to 0.037), and no statistically significant effect was found for subject age (P range: 0.18-0.24). CONCLUSION: Hepatic magnitude-based MRI PDFF estimates using three, four, five, and six echoes, and six-echo parametric maps are accurate compared to reference MRS values, and that accuracy is not meaningfully confounded by age, sex, or BMI.


Subject(s)
Liver/pathology , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods , Non-alcoholic Fatty Liver Disease/pathology , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Young Adult
8.
J Magn Reson Imaging ; 42(5): 1223-32, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25847512

ABSTRACT

PURPOSE: To assess accuracy of magnitude-based magnetic resonance imaging (M-MRI) in children to estimate hepatic proton density fat fraction (PDFF) using two to six echoes, with magnetic resonance spectroscopy (MRS) -measured PDFF as a reference standard. METHODS: This was an IRB-approved, HIPAA-compliant, single-center, cross-sectional, retrospective analysis of data collected prospectively between 2008 and 2013 in children with known or suspected nonalcoholic fatty liver disease (NAFLD). Two hundred eighty-six children (8-20 [mean 14.2 ± 2.5] years; 182 boys) underwent same-day MRS and M-MRI. Unenhanced two-dimensional axial spoiled gradient-recalled-echo images at six echo times were obtained at 3T after a single low-flip-angle (10°) excitation with ≥ 120-ms recovery time. Hepatic PDFF was estimated using the first two, three, four, five, and all six echoes. For each number of echoes, accuracy of M-MRI to estimate PDFF was assessed by linear regression with MRS-PDFF as reference standard. Accuracy metrics were regression intercept, slope, average bias, and R(2) . RESULTS: MRS-PDFF ranged from 0.2-40.4% (mean 13.1 ± 9.8%). Using three to six echoes, regression intercept, slope, and average bias were 0.46-0.96%, 0.99-1.01, and 0.57-0.89%, respectively. Using two echoes, these values were 2.98%, 0.97, and 2.72%, respectively. R(2) ranged 0.98-0.99 for all methods. CONCLUSION: Using three to six echoes, M-MRI has high accuracy for hepatic PDFF estimation in children.


Subject(s)
Fatty Liver/pathology , Liver/pathology , Magnetic Resonance Imaging , Adolescent , Adult , Child , Cross-Sectional Studies , Female , Humans , Magnetic Resonance Spectroscopy , Male , Protons , Reproducibility of Results , Retrospective Studies , Young Adult
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