GNRH1 and uterine corpus leiomyoma: 339 women with 368 hyperintense uterine fibroids on T2WI who underwent single-session HIFU ablation were enrolled, including 283 patients with 303 fibroids in the single-session HIFU (sHIFU) group and 56 patients with 65 fibroids in the HIFU pretreated with GnRH-a (Gn-HIFU) group.