有没有了解子宫Adnexa里hypoechoic structure的呀？

pelvic sono显示是 In the right adnexa there is a hypoechoic structure measuring 1.8 cm. This structure presents with peripheral vascularity and does not particularly move when external pressure is applied.
这种一般是什么情况呀？ 家庭医生没说啥。
查了一下好像接下来可以做一下doppler measurement?
另外还有一些Moderate free fluid within the pelvis. 查了一下好像比较常见？