Changes in apparent diffusion coefficients in the normal uterus during different phases of the menstrual cycle

Abstract

ABSTRACT. This study investigated the apparent diffusion coefficients (ADCs) of the uterine zonal structures (myometrium, endometrium and junctional zone) among reproductive women, and their changes during the menstrual cycle. Magnetic resonance (MR) images of seven healthy females (aged 24-31 years) were obtained during the periovulatory, luteal and menstrual phases. Diffusion-weighted imaging (DWI) was performed with a single-shot echo-planar imaging (EPI) sequence in the midsagittal plane of the uterus using three b-values (b50, 500 or 1000 s mm . Intermeasurement variation between the two ROIs ranged from 0 to 0.48610 23 mm 2 s 21 per measurement. The magnitude of these variations was comparable to reported differences between malignant and non-malignant tissues. These preliminary results, from a small number of subjects, suggest that the menstrual cycle and individual variation in pre-menopausal women should be considered when interpreting the ADC values of uterine structures.

Diffusion Tensor Imaging of the Uterine Zones Related to the Menstrual Cycle and Menopausal Status at 3 Tesla MRI

“…Studies regarding the cyclic ADC changes of uterine zones in the literature revealed that ADC values increase beginning from the proliferative phase to secretory phase, and are higher in the secretory phase, probably related to increased fluid content (4,15,19,20).…”

“…These mechanisms may be the cause of the high ADC values of the endometrial zone during the mid-secretory phase (15,(21)(22)(23). For the myometrium, edema in the secretory phase may have an effect to lower FA values, whereas myometrial contractions and relatively low water content might have increased FA values (4).…”

“…However, the thickness and signal intensities of the myometrium and especially the endometrium change during different phases of the menstrual cycle (2,3). Depending on the histologic changes in the myometrium and endometrium, variation of the apparent diffusion coefficient (ADC) values of the normal uterine zones in the different periods of the cycle is demonstrated in the literature (4,5). Diffusion-weighted imaging (DWI) can show abnormal signals reflecting pathologic foci based on differences in molecular diffusion.…”

“…Diffusion tensor imaging is the best method to evaluate the anisotropic properties of solid organs, and it, unlike DWI, permits the analysis of diffusion along multiple directions. Recently, the improvement of this technique made it a useful and complementary sequence to conventional imaging techniques for demonstrating the fiber structures of the uterus (4,8,(10)(11)(12)(13).…”

Diffusion weighted MRI for detecting and monitoring cancer: a review of current applications in body imaging

“…The difference in the ADC values between malignant and nonmalignant lesions is comparable to the variation in the ADC values of normal structures during the menstrual cycle. Thus, the phase of the menstrual cycle must be considered when characterizing or monitoring lesions with ADC (104,106,107).…”