MR Imaging of Normal Ovary in Menstruating Women: Detection Rate and Size of the Ovary and the Number and Size of the Follicle According to the Age

Purpose: To determine the rates at which normal ovaries in women of reproductive age were observed at MRI, as well as differences in the size of a normal ovary and follicles, and the number of follicles, according to age. Materials and Methods: The MRI findings in 46 patients with normal ovaries were retrospectively analysed and proven grossly at surgery and/or pathologically. The detection rate and size of the ovaries, and the number of follicles and size of the largest were determined, and differences were analyzed according to age: under 30, 30-39, and 40 years or over. Results: Among 46 patients, bilateral ovaries were detected in 39 and unilateral ovary in seven. The overall detection rate was 92.4% (85/92), varying according to age. It was 100% (18/18) in those aged under 30, 95% (38/40) in the 30-40 age group, and 85.3% (29/34) among those aged 40 or over. Ovary size ranged between 15 and 50 (average, 24.3) mm and was most commonly 20-30 mm, regardless of age (60%). The average size was 28.8 mm under 30 years of age, 25.3 mm between 30 and 39, and 20.3 mm at age 40 or over (p