Signal intensity of normal breast tissue at MR mammography on midfield: applying a random coefficient model evaluating the effect of doubling the contrast dose

Thermic effect of a meal and appetite in adults: an individual participant data meta-analysis of meal-test trials

Background

Thermic effect of a meal (TEF) has previously been suggested to influence appetite.

Objective

The aim of this study was to assess whether there is an association between appetite and TEF. Second, to examine whether protein intake is associated with TEF or appetite.

Design

Individual participant data (IPD) meta-analysis on studies were performed at the Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark. Five randomized meal-test studies, with 111 participants, were included. The included studies measured energy expenditure (EE) in respiration chambers and pre- and postprandial appetite sensations using Visual Analog Scales (VAS). The primary meta-analysis was based on a generic-inverse variance random-effects model, pooling individual study Spearman's correlation coefficients, resulting in a combined r-value with 95% confidence interval (95% CI). The I² value quantifies the proportion (%) of the variation in point estimates due to among-study differences.

Results

The IPD meta-analysis found no association between satiety and TEF expressed as the incremental area under the curve (TEF_iAUC) (r=0.06 [95% CI −0.16 to 0.28], P=0.58; I²=15.8%). Similarly, Composite Appetite Score (CAS) was not associated with TEF_iAUC (r=0.08 [95% CI −0.12 to 0.28], P=0.45; I²=0%). Posthoc analyses showed no association between satiety or CAS and TEF expressed as a percentage of energy intake (EI) (P>0.49) or TEF expressed as a percentage of baseline EE (P>0.17). When adjusting for covariates, TEF_iAUC was associated with protein intake (P=0.0085).

Conclusions

This IPD meta-analysis found no evidence supporting an association between satiety or CAS and TEF at protein intakes ∼15 E% (range 11–30 E%).

Normal breast parenchyma: contrast enhancement kinetics at dynamic MR mammography--influence of anthropometric measures and menopausal status

PURPOSE

To study T1 baseline signal intensity (SI) and contrast material enhancement kinetics of normal breast parenchyma by using dynamic contrast-enhanced (DCE) magnetic resonance (MR) mammography and to determine the influence of anthropometric measures and menopausal status on the variability of these features.

MATERIALS AND METHODS

Institutional review board approval and written informed consent were obtained. Between June 2008 and September 2011, 345 women (age range, 26-81 years; mean age, 51.3 years ± 11.6 [standard deviation]) underwent DCE MR mammography, with T1-weighted three-dimensional MR images (repetition time msec/echo time msec, 8.86/4.51; flip angle, 25°) acquired with a 1.5-T whole-body MR unit before and 1, 2, 3, 4, and 5 minutes after a gadobutrol bolus injection of 0.1 mmol per kilogram of body weight. Regions of interest were traced manually, and T1 SI of parenchyma was recorded. The influence of different predictors of T1 baseline SI and contrast enhancement was studied by using random-effects models.

RESULTS

T1 baseline SI varied considerably between women, with a mean of 167.7 ± 49.2 (71.4-424.7 [range]) and 175.9 ± 48.9 (51.8-458.3) in the right and the left breast, respectively (P < .01). T1 baseline SI increased linearly with age (P < .0001) and body weight (P < .0001). After contrast material delivery, relative percentage of enhancement was 8.1%, 13.8%, 18.2%, 22.1%, and 24.6% at 1, 2, 3, 4, and 5 minutes, respectively, but varied considerably between women. Contrast enhancement was 9.3% in the lowest quintile and 47.4% in the highest. Contrast enhancement increased with body weight (P < .01) but decreased in postmenopausal women (P < .01). Women with higher baseline T1 SI tended to have a higher contrast enhancement slope.

CONCLUSION

Anthropometric measures and menopausal status contribute to a large variability in contrast enhancement of normal breast parenchyma. This might influence the interpretation of contrast enhancement kinetics of breast lesions and current strategies for determining contrast medium dose for breast MR imaging.

Contrast enhancement kinetics of normal breast parenchyma in dynamic MR mammography: effects of menopausal status, oral contraceptives, and postmenopausal hormone therapy

OBJECTIVES

To investigate effects of menopausal status, oral contraceptives (OC), and postmenopausal hormone therapy (HT) on normal breast parenchymal contrast enhancement (CE) and non-mass-like enhancing areas in magnetic resonance mammography (MRM).

METHODS

A total of 459 female volunteers (mean age 49.1 ± 12.5 years) underwent T1-weighted 3D MRM 1-5 min after bolus injection of gadobutrol. Quantitative analysis was performed in normal breast parenchyma by manually tracing regions of interest and calculating percentage CE. Semiquantitative analysis was performed in non-mass-like enhancing areas, and signal intensity changes were characterised by five predefined kinetic curve types. The influence of OC (n = 69) and HT (n = 24) on CE was studied using random effects models.

RESULTS

Breast parenchymal enhancement was significantly higher in premenopausal than in postmenopausal women (P < 0.001). CE decreased significantly with the use of OC (P = 0.01), while HT had negligible effects (P = 0.52). Prevalence of kinetic curve types of non-mass-like enhancement differed strongly between pre- and postmenopausal women (P < 0.0001), but was similar in OC users and non-OC users (P = 0.61) as well as HT users and non-HT users (P = 0.77).

CONCLUSIONS

Normal breast parenchymal enhancement and non-mass-like enhancing areas were strongly affected by menopausal status, while they were not affected by HT use and only moderately by OC use.

KEY POINTS

Breast parenchymal enhancement at MR mammography is stronger in premenopausal than postmenopausal women. The prevalence of strong enhancing non-mass-like areas is greater before menopause. Such enhancing non-mass-like areas may impair lesion detection in premenopausal women. Breast parenchymal enhancement is only marginally affected by hormone use. Discontinuation of hormone use before MR mammography may be unnecessary.

Feasibility of a standardized ultrasound examination in patients with rheumatoid arthritis: a quality improvement among rheumatologists cohort

Background

Quality improvement is important to facilitate valid patient outcomes. Standardized examination procedures may improve the validity of US.

The aim of this study was to investigate the learning progress for rheumatologists during training of US examination of the hand in patients with rheumatoid arthritis (RA).

Methods

Rheumatologists with varying degrees of experience in US were instructed by skilled tutors. The program consisted of two days with hands-on training followed by personal US examinations performed in their individual clinics. Examinations were sent to the tutors for quality control. The US examinations were evaluated according to a scoring sheet containing 144 items. An acceptable examination was defined as > 80% correct scores.

Results

Thirteen rheumatologists participated in the study. They included a total of 104 patients with RA. Only few of the initial examinations were scored below 80%, and as experience increased, the scores improved (p = 0.0004). A few participants displayed decreasing scores.

The mean time spent performing the standardized examination procedure decreased from 34 min to less than 10 minutes (p = 0.0001).

Conclusion

With systematic hands-on training, a rheumatologist can achieve a high level of proficiency in the conduction of US examinations of the joints of the hand in patients with RA. With experience, examination time decreases, while the level of correctness is maintained. The results indicate that US may be applied as a valid measurement tool suitable for clinical practice and in both single- and multi-centre trials.