The relationship of T2WI signal intensity of uterine fibroids and the temperature curve in MR-guided high-intensity focused ultrasound (HIFU) ablation

Background/introduction MR guided high-intensity focused ultrasound (HIFU) ablation is increasingly being used worldwide to treat symptomatic uterine fibroids because of its excellent therapeutic efficacy in controlling symptoms and its excellent safety record. High signal intensity on T2WI MR images of fibroids is firstly considered a factor that induces poor ablation outcomes. Nevertheless, to our HIFU clinical practice, signal intensity on T2WI MR images is not that accurate for determining whether the fibroids are hyper-perfusion or hypo-perfusion because signal intensity on T2WI is just a relative and subjective parameter, which cannot quantify perfusion. It is demonstrated that the temperature curve (i.e. temperature change as a function of time) during HIFU treatments is a relatively accurate manifestation of fibroids’ reaction to sonication. The purpose of this study was to retrospectively study the relationship of T2WI signal intensity of uterine fibroids and the temperature curve in MR guided HIFU.