Ovarian cysts, especially when large, can be painful. If a cyst does not resolve on its own, draining the fluid from it can provide at least temporary pain relief. In some cases, the fluid will reaccumulate, and surgery may be needed for permanent relief. In other patients, the fluid will not recur or will reaccumulate slowly enough to be managed by repeated cyst punctures, thus obviating the need for surgery.

Removal of fluid from an ovarian cyst can also be used to differentiate an infected from a noninfected cyst. Ovarian cyst aspiration should generally be avoided when there is a clinical suspicion of ovarian malignancy, because of the possibility of tumor seeding.

Ovarian cysts can be aspirated transvaginally (Figure 35.1.1) or transabdominally (Figure 35.1.2), with the optimal approach depending on the location of the cyst. In most cases, the transvaginal approach is preferable, but transabdominal ultrasound guidance may be the optimal approach if the cyst extends close to the anterior abdominal wall.

Transvaginal ovarian cyst drainage is performed by cleaning the vagina with an antiseptic solution, inserting a transvaginal transducer equipped with a needle guide, and inserting a needle through the guide. Using continuous real-time guidance, the needle
is advanced into the cyst. Once it is within the cyst, the stylet is removed, a syringe is attached, and the cyst is drained. If the cyst is multilocular, all (or at least the several largest) locules can be drained by redirecting the needle into different areas.

When transabdominal guidance is used, the procedure begins by cleaning the puncture site on the anterior abdominal wall with an antiseptic solution. Guidance can be done with or without a needle guide attachment on the transducer.

When a woman undergoes in vitro fertilization, she takes medication to stimulate her ovaries to produce multiple follicles. Many of these follicles contain oocytes (i.e., eggs). The oocytes are retrieved using ultrasound-guided aspiration of the follicles. The oocytes are fertilized by incubating them with the father’s sperm, and the resultant embryos are then transferred into the woman’s uterus.

Egg retrieval is usually performed under transvaginal ultrasound guidance. In some cases, when the ovaries are located high in the pelvis and close to the anterior abdominal wall, transabdominal guidance may be the better choice (Figure 35.2.1). With either guidance approach, the needle is advanced into each follicle and fluid is aspirated. The fluid is then examined for the presence of an oocyte.

Uterine instrumentation procedures, such as dilation and curettage (D&C) and office endometrial biopsy, are generally performed blindly. There are several situations in which ultrasound guidance is valuable, including the following: