Figure 6a. Myometrial contraction in a healthy 30-year-old woman, who underwent MR imaging during a study that evaluated myometrial contractions during the menstrual phase. The half-Fourier acquisition single-shot turbo spin-echo sequence was used to obtain T2-weighted images. (a) Sagittal image obtained on cycle day 1 shows a focal area of low signal intensity in the anterior myometrium (arrows), a finding that closely simulates focal adenomyosis. (b) Sagittal image obtained on cycle day 3 shows a normal uterus with a thin and distinct junctional zone.