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

Objective: 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 evalua-tion of uterine fibroids in pre-menopausal women undergoing hysterectomy. Methods: 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 docu-mented the gross examination details per a set protocol. We compared the prespecified 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 hyster-ectomy specimen. Results: 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 sonol-ogists were reproducible (Cronbach's alpha = 0.9 for the L1, L2 and L3 dimensions of fibroids from the 3-D model). Conclusion: 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.

Automated summary

This study assessed the accuracy of 3-D surface rendering of 2-D ultrasound images of the uterus using FMRA software for mapping uterine fibroids compared to pathological evaluation. The results showed good correlation between the two methods in terms of fibroid size and location. Inter-observer analysis also demonstrated reproducibility of measurements from two sonologists using the 3-D model.