Prediction using T2-weighted magnetic resonance imaging-based radiomics of residual uterine myoma regrowth after high-intensity focused ultrasound ablation.

<bold>Objectives: </bold>To develop and evaluate magnetic resonance imaging (MRI)-based radiomics models for predicting residual myoma regrowth within 1 year after high-intensity focused ultrasound (HIFU) ablation of uterine myomas.<bold>Methods: </bold>A retrospective analysis of residual myoma regrowth within 1 year was performed on 428 myomas in 339 patients who were diagnosed with uterine myoma and treated with HIFU ablation in two hospital centers. In total, 851 radiomics features were extracted from T2-weighted images (T2WI) obtained 1 day after HIFU ablation, and the least absolute shrinkage and selection operator in the training cohort (n = 243) was employed to select radiomics features. Support vector machines were adopted to develop radiomics, clinicoradiological and combined radiomics-clinical models to predict residual myoma regrowth, defined as an increase in residual myoma volume of > 10% between that at day 1 post HIFU and that at follow-up MRI within 1 year. These models were validated in both internal (n = 81) and external (n = 104) test cohorts. The predictive performance and clinical application of these models were assessed using receiver-operating-characteristics-curve analysis, the area under the curve (AUC) and decision-curve analysis.<bold>Results: </bold>The AUCs of the T2WI-based radiomics prediction model in the internal and external test cohorts were 0.834 (95% CI, 0.747-0.920) and 0.801 (95% CI, 0.712-0.889), respectively, and those of the clinicoradiological model were 0.888 (95% CI, 0.816-0.960) and 0.912 (95% CI, 0.851-0.973), respectively. The combined model had better predictive performance than either the radiomics or the clinicoradiological model, with AUC values of 0.922 (95% CI, 0.857-0.987) and 0.930 (95% CI, 0.880-0.980) in the internal and external test cohorts, respectively. Decision-curve analysis also indicated that application of the combined model has clinical value, this model achieving more net benefits than the other two models.<bold>Conclusion: </bold>T2WI-based radiomics features can predict effectively the occurrence of residual myoma regrowth within 1 year after HIFU ablation of uterine myomas, which serves as an accurate and convenient reference for clinical decision-making. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]