MRI Analysis Of Adverse Reactions After HIFU Ablation Of Uterine Fibroids

Objective: To observe and analyze the adverse reactions of uterine fibroids after high focus ultrasound(HIFU)ablation and the therapeutic effects and adverse reactions of different T2 signal fibroids before surgery.Methods: Preoperative and postoperative MRI data of 103 patients with uterine fibroids treated with HIFU were collected.According to T2 signal intensity,it was divided into T2 low signal group,T2 equal signal group and T2 high signal group.According to the degree of ablation,the NPVR ≥ 70 % was divided into the ablation standard group,and the ablation rate NPVR < 70 % was divided into insufficient ablation.The ablation effect of fibroids with different T2 signals before operation and the adverse reactions(abdominal wall edema,endometrial injury,pelvic effusion,pelvic fascia swelling,piriformis edema,presacral fascia swelling,sacral bone marrow edema,rectal edema)were analyzed.Adverse reactions were used as dependent variables,and baseline characteristics and T2 signal characteristics were used as independent variables.Kruskal-Wallis H test and chi-square test were used to analyze whether there were differences and correlations between preoperative uterine baseline data and myoma T2 signal on the occurrence of adverse reactions.Results: In 103 cases of uterine myoma after HIFU operation,abdominal wall edema(52.40%),mucosal injury(18.40%),pelvic effusion(43.70%),pelvic fascia swelling(32.00%),anterior sacral fascia edema(58.30%),piriformis muscle edema(49.50%),sacral bone marrow edema(21.40%)and rectal edema(20.40%)occurred.Abdominal wall edema(x2=15.529,p<0.001),pelvic fascia swelling(x2=5.283,p=0.071),anterior sacral fascia edema(x2=11.218,p=0.004),piriformis myoedema(x2=19.278,p<0.001)and sacral bone marrow edema(x2=6.511,p=0.039)were statistically significant.The difference of fibroids in different T2 signal groups was statistically significant(x2=7.188,p=0.03)between ablation compliance(NPVR ≥70%)and underablation(NPVR<70%).The ablation compliance of fibroids in the T2 high-signal group was lower than that in the T2 low-signal group(p<0.05).The frequency of abdominal wall edema,anterior sacral fascia edema,piriformis myoedema and sacral bone marrow edema after myoma operation in T2 high signal group was significantly higher than that in T2 low signal group(p<0.05).There were no significant differences in mucosal injury(x2=2.891,p=0.236),pelvic effusion(x2=0.006,p=0.997)and rectal edema(x 2 =1.896,p=0.388)among fibroids of different T2 signal groups.Bivariate analysis showed that fibroid T2 signal(low/equal/high)was positively correlated with abdominal wall edema,anterior sacral fascia swelling,piriformis myoedema and sacral bone marrow edema,but negatively correlated with ablation reach(p < 0.05).In addition,age,fibroid diameter,fibroid volume,abdominal wall thickness and distance from fibroid to sacrum were positively correlated with abdominal wall edema(p < 0.05).Sacrococcygeal injuries(piriformis myoedema,sacral bone marrow edema,rectal edema)were negatively correlated with myoma-sacral distance(p<0.05).Conclusions:Preoperative T2 WI ablation of high-signal fibroids has a lower achieving effect than low-signal fibroids,and the probability of adverse reactions in high-signal fibroids is higher than that in isosignal fibroids and low-signal fibroids.Therefore,low-signal fibroids at T2 are more suitable for HIFU ablation.