Apparent diffusion coefficient of normal breast tissue during the menstrual cycle at 3 Tesla

Abstract

Introduction Diffusion-weighted magnetic resonance imaging (DW-MRI) is a quantitative MRI technique that provides physiological information by measuring the degree of water molecule diffusion within the extracellular space. It gives a quantitative measurement known as the apparent diffusion coefficient (ADC) value. The aim of the study is to show the influence of the menstrual cycle on breast ADC values and the relationship of the ADC to transverse relaxation (T2) value. Methods Female volunteers had one MRI scan per week over 4 weeks using a 3 T MRI scanner. The ADC of the fibroglandular tissue was measured using a single-shot SE-EPI with four b values (0, 50, 150, and 800 s/mm2). The T2 relaxation time was measured using T2w turbo spin echo (TSE) with four echo times (20, 40, 60, and 80 ms). ADC and T2 maps were generated automatically by standard Philips software. Results The study was performed on 11 healthy volunteers (23 to 41 years old) with a regular menstrual cycle. There is no significant difference between ADC and T2 values for the 4 weeks. Pearson's correlation coefficient indicated a negative correlation between ADC and T2 values. See Table 1. Table 1 Parameter Week 1 Week 2 Week 3 Week 4 ADC (×10-3 mm2/s)  Fibroglandular tissue 1.7 ± 0.2 1.7 ± 0.3 1.7 ± 0.3 1.7 ± 0.3 T2 (ms)  Fibroglandular tissue 57.6 ± 7 58 ± 7 58.7 ± 8 60 ± 10  Adipose tissue 78 ± 4 77 ± 4 77 ± 4 77 ± 4 Data presented as mean ± SD. Conclusion The study shows that ADC values are not affected by the normal hormonal fluctuations during the menstrual cycle.