Focused ultrasound therapy for reducing recurrence of vulvar lichen simplex chronicus in rats: efficacy and mechanism

To explore the changes of collagen fibrosis in the vulva skin of SD rats with lichen simplex chronicus (LSC) after focused ultrasound therapy and explore the mechanism by which focused ultrasound reduces the recurrence of vulvar LSC. Fifty female SD rat models of vulvar LSC were established and randomly divided into the treatment group and the control group ( =25) for treatment with focused ultrasound and sham treatment, respectively. Before and after the treatment, vulvar skin tissues were sampled to observe the pathological changes with HE staining and assess the density of collagen fibers using Masson staining. The ultrastructure of the collagen fibers in the superficial dermis was observed using transmission electron microscopy. The expressions of notch1 and c-fos in the vulvar tissue were detected by immunohistochemistry and Western blotting. After 4 weeks of focused ultrasound therapy, 16% (4/25) of the rats in the treatment group showed lesion progression to LSIL, 4% (1/25) still had LSC, and 80% (20/2