The researchers are doing this study to see how well multiparametric ultrasound (mpUS) imaging can evaluate vaginal tissue before and after IVRT. IVRT is routinely used to treat endometrial cancer but can cause damage to the vaginal tissue (vaginal toxicity). Side effects of vaginal toxicity can include vaginal dryness, itching, soreness, discharge, narrowing or shortening of the vagina (stenosis), and vaginal fibrosis (hardening), which can affect sexual function. The researchers will also look at whether participants are able to complete (tolerate) all mpUS imaging for this study.