Proton density water fraction as a reproducible MR‐based measurement of breast density

2021 ◽  
Author(s):  
Leah C. Henze Bancroft ◽  
Roberta M. Strigel ◽  
Erin B. Macdonald ◽  
Colin Longhurst ◽  
Jacob Johnson ◽  
...  
Keyword(s):  
Breast Density ◽  
Proton Density ◽  
Water Fraction

scholarly journals An automated approach for the optimised estimation of breast density with Dixon methods

2020 ◽  
Vol 93 (1106) ◽  
pp. 20190639 ◽  
Author(s):  
Rosie Goodburn ◽  
Evanthia Kousi ◽  
Alison Macdonald ◽  
Veronica Morgan ◽  
Erica Scurr ◽  
...  
Keyword(s):  
Breast Density ◽  
Spatial Gradient ◽  
Breast Volume ◽  
Absolute Increase ◽  
Water Fraction ◽  
Total Percentage ◽  
Automated Method ◽  
Image Volume ◽  
Text Images ◽  
Uniform Scaling

Objective: To present and evaluate an automated method to correct scaling between Dixon water/fat images used in breast density (BD) assessments. Methods: Dixon images were acquired in 14 subjects with different T1 weightings (flip angles, FA, 4°/16°). Our method corrects intensity differences between water ([Formula: see text]) and fat ([Formula: see text]) images via the application of a uniform scaling factor (SF), determined subject-by-subject. Based on the postulation that optimal SFs yield relatively featureless summed fat/scaled-water ([Formula: see text]) images, each SF was chosen as that which generated the lowest 95th-percentile in the absolute spatial-gradient image-volume of [Formula: see text] . Water-fraction maps were calculated for data acquired with low/high FAs, and BD (%) was the total percentage water within each breast volume. Results: Corrected/uncorrected BD ranged from, respectively, 10.9–71.8%/8.9–66.7% for low-FA data to 8.1–74.3%/5.6–54.3% for high-FA data. Corrected metrics had an average absolute increase in BD of 6.4% for low-FA data and 18.4% for high-FA data. BD values estimated from low- and high-FA data were closer following SF-correction. Conclusion: Our results demonstrate need for scaling in such BD assessments, where our method brought high-FA and low-FA data into closer agreement. Advances in knowledge: We demonstrated a feasible method to address a main source of inaccuracy in Dixon-based BD measurements.

scholarly journals Proton density water fraction as a biomarker of bone marrow cellularity: Validation in ex vivo spine specimens

2014 ◽  
Vol 32 (9) ◽  
pp. 1097-1101 ◽  
Author(s):  
Iain J. MacEwan ◽  
Nicholas E. Glembotski ◽  
Darryl D’Lima ◽  
Won Bae ◽  
Koichi Masuda ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Ex Vivo ◽  
Proton Density ◽  
Water Fraction ◽  
Bone Marrow Cellularity ◽  
Marrow Cellularity

scholarly journals A Phantom System Designed to Assess the Effects of Membrane Lipids on Water Proton Relaxation

2018 ◽  
Author(s):  
Oshrat Shtangel ◽  
Aviv A. Mezer
Keyword(s):  
Membrane Lipids ◽  
Magnetization Transfer ◽  
Membrane Lipid ◽  
Water Proton ◽  
Proton Relaxation ◽  
Proton Density ◽  
Brain Lipids ◽  
Water Fraction ◽  
Lipid Environment

AbstractPurposeQuantitative magnetic resonance imaging (qMRI) provides a method for the non-invasive study of brain structure and associated changes, expressed in physical units. qMRI parameters have been shown to reflect brain tissue composition such as myelin. Nevertheless, it remains a major challenge to identify and quantify the contributions of specific molecular components to the MRI signal. Here, we describe a phantom system that can be used to evaluate the contribution of human brain lipids to qMRI parameters.MethodsA thin layer evaporation-hydration technique was used to formulate liposomes that mimic the physiological bi-layered membrane lipid environment. We then applied quantitative clinical MRI techniques with adjusted bias corrections in order to test the ability of the phantom system to estimate multiple qMRI parameters such as proton density (PD), T1, T2, T2* and magnetization transfer (MT).ResultsThe results indicated that phantoms composed of various lipids could provide a stable and reliable estimation of qMRI parameters. In addition, the calculated water fraction (WF) maps for the phantoms were found to accurately represent the true WF volumes.ConclusionWe have successfully created a biologically relevant liposome phantom system whose lipid composition can be fully controlled. This system can be used to measure the contributions of lipids to qMRI parameters under conditions that are relevant to in-vivo human scans.

Mandate Suggested for Breast Density Reporting

2011 ◽  
Vol 44 (19) ◽  
pp. 4
Author(s):  
MARY ELLEN SCHNEIDER
Keyword(s):  
Breast Density

Breast Density Predicts Risk of Recurrence After Treatment

2007 ◽  
Vol 37 (2) ◽  
pp. 4
Author(s):  
BRUCE JANCIN
Keyword(s):  
Breast Density ◽  
Risk Of Recurrence

Battles Brew Over Disclosing Breast Density to Patients

2011 ◽  
Vol 41 (19) ◽  
pp. 53
Author(s):  
MARY ELLEN SCHNEIDER
Keyword(s):  
Breast Density

Magnetic resonance image attributes of the bovine ovarian follicle antrum during development and regression

Reproduction ◽  
2000 ◽  
pp. 311-323 ◽  
Author(s):  
JL Hilton ◽  
GE Sarty ◽  
GP Adams ◽  
RA Pierson
Keyword(s):  
Magnetic Resonance ◽  
Relaxation Rate ◽  
Follicular Fluid ◽  
Magnetic Resonance Image ◽  
Follicular Development ◽  
Physiological Status ◽  
Proton Density ◽  
Dominant Follicle ◽  
Rate Heterogeneity ◽  
Pixel Value

The magnetic resonance images and maps of bovine ovaries acquired at defined phases of follicular development and regression were studied to determine whether magnetic resonance image attributes of the follicular antrum reflect the physiological status of dominant and subordinate ovarian follicles. Ovariectomies were performed at day 3 of wave one, day 6 of wave one, day 1 of wave two and at >/= day 17 after ovulation. The timings of ovariectomies were selected to acquire growing, early static, late static and regressing follicles of the first wave and preovulatory follicles of the ovulatory wave. Pre-selection and subordinate follicles were also available for analysis. Serum samples were taken on the day of ovariectomy and follicular fluid samples were taken after imaging. Numerical pixel value and pixel heterogeneity in a spot representing approximately 95% of the follicular antrum were quantified in T(1)- and T(2)-weighted images. T(1) and T(2) relaxation rates (T(1) and T(2)), proton density, apparent diffusion coefficients and their heterogeneities were determined from the computed magnetic resonance maps. The antra of early atretic dominant follicles showed higher T(2)-weighted mean pixel value (P < 0.008) and heterogeneity (P < 0. 01) and lower T(2) heterogeneity (P < 0.008) than growing follicles. Subordinate follicles in the presence of a preovulatory dominant follicle had higher T(1), T(1) heterogeneity, proton density, proton density heterogeneity, and lower mean pixel value in T(1)-weighted images than subordinate follicles of the anovulatory wave (P < 0.04). T(1) relaxation rate heterogeneity and proton density heterogeneity were positively correlated with follicular fluid oestradiol concentration (r = 0.4 and 0.3; P < 0.04). T(2) relaxation rate heterogeneity was positively correlated with follicular fluid progesterone concentration (r = 0.4; P < 0.008). Quantitative differences in magnetic resonance image attributes of the antrum observed among phases of follicular development and regression coincided with changes in the ability of the dominant follicle to produce steroid hormones and ovulate, and thus were indicative of physiological status and follicular health.

Assessment of Antimicrobial Activity and total Polyphenol Content of Rosa multiflora and Rosa wichuraiana

2019 ◽  
Vol 10 (04) ◽  
pp. 646-650
Author(s):  
Hyeusoo Kim ◽  
Kyeong Won Yun
Keyword(s):  
Antimicrobial Activity ◽  
Ethyl Acetate ◽  
Antimicrobial Agents ◽  
Ethyl Acetate Fraction ◽  
Rosa Multiflora ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Water Fraction ◽  
Total Polyphenol Content ◽  
Rosa Species

The fruit of Rosa multiflora has been used as traditional herbal medicine in Asian countries. The present investigation was undertaken to study the antimicrobial activity and total polyphenol content of hexane, ether, ethyl acetate, water fraction of methanol extract of fruit and flower from Rosa multiflora and Rosa wichuraiana. Antimicrobial activity of the mentioned fractions against 3 gram-positive and 4 gram-negative bacteria using disk diffussion method. The measurement of minimal inhibition concentration (MIC) showed that the ethyl acetate fraction of the two Rosa species is the most effective against the tested bacteria. The total polyphenol content of ethyl acetate fraction of the two Rosa species is higher than the other fractions. The results indicate the antimicrobial activity was related with the total polyphenol content and the fruit and flower of the two Rosa species can be considered as a natural source of antimicrobial agents.

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