Automated calculation of ovarian follicular diameters using three dimensional sonography in women undergoing in vitro fertilization (IVF): a prospective evaluation of a novel software

The objective of this study was to prospectively evaluate a novel software program that automatically retrieves, out of a 3D ovarian volume, the X, Y, Z diameter, the mean follicular diameter (MFD) and the relaxed follicular diameter (RFD) of each individual ovarian follicle. Prospective study. This study was conducted on 10 ovarian follicles from 3 separate 3D ovarian volumes. Two independent investigators, blind to each others' results, manually derived the X, Y and Z diameters of each follicle three times. In the sectional plane interface, the X and Y diameters were obtained in the A plane and the Z diameter was obtained in the B plane. Next, each investigator automatically derived the diameters of each follicle three times using the automated follicular assessment software. The new software uses a four-stage segmentation pipeline to segment the volumetric B-mode data. Then the best-fit ellipsoid is used to measure the diameters of each follicle. For each follicle the RFD is defined as the diameter of a perfect sphere, given that the volume of the sphere is equal to the calculated follicular volume. The required time and the accuracy of diameter measurements were calculated in addition to inter/intra observer variability for each modality. The accuracy of the software was assessed by comparing the measured MFD for each follicle to the automated MFD and RFD. Descriptive statistical analysis was performed. Overall there was no statistical difference, on a per follicle basis, between the measured MFDs and the calculated MFDs and RFDs. The manual method had significantly increased intra-observer variability when compared to the automated method (P<0.05). The inter-observer variability approached statistical significance for the manual method (P=.08) with measurements differing by as much as 26% between observers. The average time required for the automated software to derive the diameter of all of the chosen follicles in an ovarian volume (5.8 seconds) was significantly less than the average time required for the manual method (56.8 seconds) (P