Menstrual-Cycle Dependence of Breast Parenchyma Elasticity: Estimation With Magnetic Resonance Elastography of Breast Tissue During the Menstrual Cycle

Magnetic resonance elastography (MRE) is a promising diagnostic method that produces images with a contrast proportional to the elasticity of the tissue. This study investigated using MRE the dependence of breast tissue elasticity from the menstrual cycle of healthy volunteers.Five volunteers (age 26-36) without breast disease and contraceptive medication were examined once weekly over 2 menstrual cycles. Examinations were performed with a 1.5 T magnet (ACS-NT, Philips Medical Systems, Best, The Netherlands). Low-frequency mechanical waves (65 Hz) were transmitted into the tissue by an oscillator. By means of a motion-sensitive spin-echo sequence, mechanical waves were displayed within the phase of the MR image and phase images were used to reconstruct the local distribution of elasticity. The elasticity of fibroglandular tissue and adipose breast tissue was analyzed individually, and the median and mean values of elasticity over the menstrual cycle were determined.All volunteers presented a repeating pattern concerning the elasticity over the 2 cycles. After 5 days of the onset of menses, the median value of elasticity for fibroglandular adipose tissue declined significantly by -29% (P = 0.010). After the second week of the cycle, fibroglandular tissue showed again an increase in elasticity (P = 0.028). The highest median values of elasticity were obtained during days 11 to 23 with an increase of up to 35%. For adipose tissue, only a slight and not significant variation of elasticity during the menstrual cycle was determined.MRE is able to measure a dependence of tissue elasticity on the menstrual cycle.