| This ovary contains a dominant follicle (DF). The ultrasonogram shows that the follicle penetrates deep into the center of the ovary. Fluid-filled cavities generate a black image while dense tissue like the ovarian stroma (OS) generates a gray to white image. This follicle could easily be palpated per rectum. However, the exact size of the follicle would be difficult to ascertain. Ultrasound technology allows changes in diameter to be measured precisely. |