Magnetic Resonance Imaging-guided Focused Ultrasound Surgery in a Swine Adenomyosis Model

The purpose of this study was to explore the feasibility of magnetic resonance imaging-guided focused ultrasound surgery (MRgFUS) for the treatment of an adenomyosis model of Bama pigs and the changes in the level of oxytocin receptor (OTR), vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) in the myometrium tissues of Bama pigs after MRgFUS.

Three Bama pig models of adenomyosis were established by autologous endometrial implantation and evaluated by magnetic resonance imaging, computed tomography, and hematoxylin-eosin (H&E) staining. After the successful construction of the model, the pigs underwent MRgFUS. Before the modeling surgery, three months after the modeling, and two months after ablation, the myometrium tissues were clipped, then embedded and H&E stained for immunohistochemical examination. The average optical density of OTR, VEGF, and COX-2 were semi-quantitatively analyzed.

The adenomyosis models were established in all Bama pigs and confirmed by magnetic resonance imaging, computed tomography and H&E staining. Magnetic resonance imaging and computed tomography examination showed that the uterine wall at the modeling site was significantly thickened with uneven enhancement after contrast injection. All Bama pigs with adenomyosis lesions underwent MRgFUS without complications. The expression level of OTR and COX-2 in the myometrium increased three months after modeling surgery and decreased two months after MRgFUS. The expression level of VEGF decreased two months after MRgFUS.

Autologous endometrial implantation is effective in establishing the adenomyosis model of Bama pigs. It is feasible to treat adenomyosis in the Bama pig model with MRgFUS. The levels of OTR, COX-2 and VEGF in the local myometrium decreased after MRgFUS, which may be associated with symptom relief after treatment.