Three-dimensional sonographic and power Doppler characterization of ovaries in late follicular phase

To determine ovarian blood flow characteristics using three-dimensional power Doppler ultrasound.

We examined 30 patients (30 cycles) prior to the start of their in vitro fertilization treatment in the late follicular phase using three-dimensional power Doppler ultrasound. The volume, vascularization index, flow index, vascularization flow index, mean grayness and the presence of the dominant follicle were determined for each ovary separately.

The dominant follicle could be detected in 24 out of 30 cycles (80.0%). The volume of the dominant ovary was 9.9 (standard deviation, 4.0) cm3 and the volume of the non-dominant ovary 6.8 (standard deviation, 2.8) cm3 (P < 0.001). Mean grayness in the dominant ovary was 43.3 (standard deviation, 5.0) and in the non-dominant 47.2 (standard deviation, 4.0) (P < 0.001), but no other differences could be observed between dominant and non-dominant ovaries. The shell with a diameter of 2 mm surrounding the dominant follicle had a higher vascularization index (mean, 9.0; standard deviation, 5.9) and vascularization flow index (mean, 4.2; standard deviation, 2.8) than the whole dominant ovary (mean, 5.5; standard deviation, 2.5 and mean, 2.5; standard deviation, 1.3, respectively) (P = 0.003 and 0.002, respectively). In the cycles without a dominant follicle (n = 6), flow index (mean, 50.0; standard deviation, 5.9) and vascularization flow index (mean, 7.3; standard deviation, 6.2) on the left side were higher than on the right side (mean, 40.2; standard deviation, 3.1; mean, 1.5; standard deviation, 1.4; P-values 0.013 and 0.046, respectively).

In the dominant ovary, the volume was higher and mean grayness lower than in the non-dominant ovary. The vascularization index in the shell surrounding the dominant follicle was higher than the average vascularization index in the whole dominant ovary. In addition, there were differences in the vascularization and flow indices between right and left ovaries, which may be related to the anatomical difference in the venous drainage between right and left ovaries.