Accuracy of 3-D Surface Rendering of 2-D Ultrasound Images of the Uterus Using a Novel Software in Mapping Uterine Fibroids

Abstract

Three-dimensional surface rendering of 2-D ultrasound images of the uterus in mapping uterine fibroids is a fast-evolving imaging technique that holds great potential for gynecology. The purpose of this study was to assess the accuracy of 3-D surface rendering of 2-D ultrasound images of the uterus using a new Fibroid Mapping Reviewer Application (FMRA) software for mapping uterine fibroids as compared with the pathological evaluation of uterine fibroids in pre-menopausal women undergoing hysterectomy. We enrolled women aged 35-55 y scheduled for hysterectomy for symptomatic fibroids at a tertiary care hospital from 2019 to 2021. Per pre-set guidelines, we recorded 2-D images and videos of the uterus with fibroids during the transvaginal ultrasound. The recordings were transferred through USB, loaded in the FMRA software and post-processed to generate a 3-D rendered uterus model. An experienced pathologist assessed and documented the gross examination details per a set protocol. We compared the pre-specified dimensions related to the size (L1, L2) and location (X, Y) of fibroids between the 3-D model and the pathologist's assessment of the hysterectomy specimen. A total of 25 fibroids in 25 women, the single largest per woman, were considered for analysis. The two methods had good correlation with respect to size (for L1, R²=0.9723, and for L2, R²=0.9784) and location (for X, R²=0.9618, and for Y, R²=0.9753). Inter-observer analysis revealed that measurements from two sonologists were reproducible (Cronbach's α=0.9 for the L1, L2 and L3 dimensions of fibroids from the 3-D model). The FMRA is a novel tool for mapping fibroids. With its proven accuracy, it will be helpful in planning surgeries and during guided procedures for managing uterine fibroids.