A Voluson E8 ultrasound system with coded contrast imaging (GE Healthcare, Milwaukee, WI) was used. The mechanical index of the instrument was set at 0.12–0.18. An RIC5-9-D transvaginal volume transducer with a frequency range of 5.0–9.0 MHz and scanning angles from 0 to 179° was used in the examinations.
An SF6 microbubble agent (SonoVue, Bracco S.p.A., Milan, Italy) was used to prepare the contrast medium for four-dimensional (4D) HyCoSy. Specifically, the content in one SonoVue vial was first suspended with 5 mL of 0.9% normal saline, followed by further dilution of 2.5 mL with up to 20 mL of 0.9% normal saline using a 20 mL syringe. The diluted solution of SonoVue was used in the HyCoSy examination.
The 4D HyCoSy was conducted within 3–7 days after menstruation. Before the start of the procedure, we checked the mobility of both of the ovaries following a previously published method [17 ]. The examinations and evaluation reports were performed by five sonographers, each of whom had more than 5 years of experience in using ultrasonography to perform gynecologic and obstetric examinations.
An SF6 microbubble agent (SonoVue, Bracco S.p.A., Milan, Italy) was used to prepare the contrast medium for four-dimensional (4D) HyCoSy. Specifically, the content in one SonoVue vial was first suspended with 5 mL of 0.9% normal saline, followed by further dilution of 2.5 mL with up to 20 mL of 0.9% normal saline using a 20 mL syringe. The diluted solution of SonoVue was used in the HyCoSy examination.
The 4D HyCoSy was conducted within 3–7 days after menstruation. Before the start of the procedure, we checked the mobility of both of the ovaries following a previously published method [17 ]. The examinations and evaluation reports were performed by five sonographers, each of whom had more than 5 years of experience in using ultrasonography to perform gynecologic and obstetric examinations.