In vivo perfusion, T1, and T2 measurements in the female pelvis during the normal menstrual cycle:: A feasibility study

Purpose: To quantify T-1, T-2, and regional tissue perfusion in uterine tissues, with MR imaging in clinically feasible imaging times, using echo planar imaging (EPI) techniques over a single menstrual cycle. Materials and Methods: A total of 24 healthy ovulating women were scanned; however, complete data sets through the menstrual cycle were not obtained from all women. Three scans were performed to coincide prospectively with the follicular, periovulatory, and luteal phases of the cycle. T, and perfusion were measured simultaneously using flow alternating inversion recovery (FAIR), while T2 was measured using a single Hahn spin-echo (SE) EPI sequence. Results: Between the follicular and periovulatory phases, statistically significant increases (P < 0.05) were seen for the T-2 of the endometrium and perfusion of the myometrium as well as the T-2/T-1 ratio for both endometrium and myometrium. A statistically significant decrease was seen in the endometrial T-2 between the periovulatory and luteal phases of the cycle. Tissue differentiation was achieved using the parameters measured, with T-1 and T-2 being statistically greater for the endometrium than for the myometrium, and endometrial perfusion being statistically lower than myometrial perfusion. Conclusion: These results show the feasibility of using these techniques to measure T-1, T-2, and perfusion in uterine tissues and of extending this work to study pathological conditions.