Breast fat volume measurement using wide-bore 3 T MRI: comparison of traditional mammographic density evaluation with MRI density measurements using automatic segmentation.

AIM: To compare magnetic resonance imaging (MRI)-derived breast density measurements using automatic segmentation algorithms with radiologist estimations using the Breast Imaging Reporting and Data Systems (BI-RADS) density classification. MATERIALS AND METHODS: Forty women undergoing mammography and dynamic breast MRI as part of their clinical management were recruited. Fat-water separated MRI images derived from a two-point Dixon technique, phase-sensitive reconstruction, and atlas-based segmentation were obtained before and after intravenous contrast medium administration. Breast density was assessed using software from Advanced MR Analytics (AMRA), Linköping, Sweden, with results compared to the widely used four-quartile quantitative BI-RADS scale. RESULTS: The proportion of glandular tissue in the breast on MRI was derived from the AMRA sequence. The mean unenhanced breast density was 0.31±0.22 (mean±SD; left) and 0.29±0.21 (right). Mean breast density on post-contrast images was 0.32±0.19 (left) and 0.32±0.2 (right). There was "almost perfect" correlation between pre- and post-contrast breast density quantification: Spearman's correlation rho=0.98 (95% confidence intervals [CI]: 0.97-0.99; left) and rho=0.99 (95% CI: 0.98-0.99; right). The 95% limits of agreement were -0.11-0.08 (left) and -0.08-0.03 (right). Interobserver reliability for BI-RADS was "substantial": weighted Kappa k=0.8 (95% CI: 0.74-0.87). The Spearman correlation coefficient between BI-RADS and MRI breast density was rho=0.73 (95% CI: 0.60-0.82; left) and rho=0.75 (95% CI: 0.63-0.83; right) which was also "substantial". CONCLUSION: The AMRA sequence provides a fully automated, reproducible, objective assessment of fibroglandular breast tissue proportion that correlates well with mammographic assessment of breast density with the added advantage of avoidance of ionising radiation.

Non-verbal behavior as courtship signals: the role of control and choice in selecting partners.

In this work, we provide evidence based on direct observation of behavior in encounters of opposite-sexed strangers, that women initiate and "control" the outcome. In the first minute of these videotaped 10-min interactions, neither female "solicitation" behavior nor "negative" behavior is strongly related to professed interest in the man, while female "affirmative" behavior at this stage modulates male verbal output in later stages (4-10 min). Although the rate of female courtship-like behavior is significantly higher in the first minute, it is only in the fourth to tenth minute that the rate of female courtship-like behavior is correlated with professed female interest. We hypothesize that this serves as a strategic dynamic reflecting sexual asymmetry in parental investment and the potential cost of male deception to women. Ambiguous protean behavioral strategies veil individuals' intentions and make their future actions unpredictable. These behavioral strategies may result in men's overestimation of female sexual interest.

Fuzziness of nonverbal courtship communication unblurred by motion energy detection.

A new method for the assessment of qualitative description of nonverbal behavior (automatic movie analysis) is introduced. This model-free method does not use any assumptions on the structure and organization of nonverbal behavior. Cross-cultural comparison (Germany, Japan) of unobtrusively filmed initial interactions between 2 opposite-sex strangers revealed no consistent courtship repertoire of directly observable behavior categories. Furthermore, an extensive analysis of gaze behavior and speech revealed differences between the countries but also showed no consistent relation to interest. Motion energy detection demonstrated in both cultures that female movement quality score (number of movements, duration, size, speed, and complexity) covaries with female interest. This effect is in concordance with the theory that in early stages of interactions manipulative efforts occur in order to avoid possible deception in high-risk situations.