The Clinical Study Of Oxytocin-assisted Ultrasound Ablation For Treatment Of Uterine Fibroids

Background:Uterine fibroids are the most common benign tumors of reproductive age women.The tumors often cause symptoms such as abnormal menstruation, pelvic pressure andadverse reproductive outcomes. The patients with significant symptoms usually needclinical intervention. With the development of society and medical advances, morepatients want to preserve their uterus even fertility while in the treatment of myomas.Ultrasound ablation is a safe and effective technique for treating symptomatic uterinefibroids, it could become a new non-invasive treatment option for fibroid patients whowant to preserve their uterus. OT (Oxytocin) is an effective uterine contraction agent,studies have confirmed that OT can shorten the treatment time and improve energyefficiency for ultrasound ablation of uterine fibroids. It suggest that OT may have asignificant impact on the blood perfusion of uterine fibroids and can improve thetreatment efficiency of ultrasound ablation for uterine fibroids.Objective:1. To explore the blood perfusion changes of uterine fibroids before and after theuse of OT.2. To observe the effect of OT on the ultrasound ablation for uterine fibroids.Methods:1. The effect of OT on the blood perfusion of uterine fibroids（Self-control study）：Contrast-enhanced ultrasound (CEUS) was performed for the uterine fibroids before andafter using OT, respectively, the dynamic images was analyzed with the software andTIC (time-intensity curve) was drawn to observe the blood perfusion changes of theuterine fibroids. If the effect of low dose OT was poor, the dose was increased to0.4U/min. 2. The effect of OT on the ultrasound ablation in the treatment of uterine fibroids(Randomized control study)： Patients were randomly divided into2groups. Theexperimental group was administered OT and control group received normal saline. Thevolume ablation rate and the energy required for ablating per unit volume of fibroidswere calculated by CEUS or contrast-enhanced MRI, differences between the twogroups were compared.Results:1. A total of52patients with54fibroids were enrolled in this study. Significanteffect was observed in48patients with50fibroids, the TTP (time to peak), Imax(maximum intensity), MTT (mean transit time) of fibroids were (15.8±4.9)s,(108.8±69.8)%,(73.4±34.4)s and (31.4±19.7) s,(17.1±20.4)%、(130.1±121.6)sbefore and after continuous intravenous injection0.1U/min OT for15minutes,respectively. There were significant differences before and after the use of OT (P<0.05).Four patients with low dose OT hadn’t observe significant changes of blood perfusion,increase the dose to0.4U/min had a further observation. The Imax of fibroids was(125.0±18.2)%、(103.9±37.5)%and (86.4±11.4)%, respectively.2. A total of17patients with17fibroids were observed, the OT group included10cases and the control group included7cases.In these two groups, the average age was (36.3±5.6)years and (39.7±2.9)years,respectively,(P value was0.196); the mean diameter was (64.2±8.9)cm and(61.3±8.7)cm, respectively (P value was0.525);the mean abdominal wall thickness was(23.0±4.3)mm and (27.8±5.1)mm, respectively (P value was more than0.05);thedistance from abdominal skin surface to the deepest wall of fibroids was(92.3±12.6)mm and (94.1±14.0)mm, respectively(P value was0.896). All aboveindicators had no statistical difference.The volume ablation rate and the energy required for ablating per unit volume offibroids were (88.5±11.8)%、(4.8±1.6) J/mm3and (69.2±15.9)%、(7.5±1.9) J/mm3for OT group and control group, respectively. The P values were less than0.05. Theirradiation time for per unit volume of fibroids were (9.2±3.3)s/cm3and (12.6±4.6)s/cm3,(P value was0.09). The OT group required less energy for ablating perunit volume of fibroids and had a higher ablation rate. There was statistically significantdifference between the two groups.Conclusion:Oxytocin continuous intravenous injection at a dose of0.1U/min can significantlyreduce the blood perfusion of majority uterine fibroids, which may help to enhance thetherapeutic efficacy for ultrasound ablation in the treatment of uterine fibroids.