The Comparative Study Of Prognosis In Different Gray-Scale Change During The Treatment Of Fibroids By High Intensity Focused Ultrasound

Background:It is tested by a large number of clinical researches that High Intensity Focused Ultrasound (HIFU) is safe and effective. Especially many scholars have already confirmed the treasure to intramural fibroid through HIFU. It has become one of the available methods to treat fibroid clinically for the patients. The reduction degree of the muscular tumor after the HIFU treatment is the most important concern during follow-up visit. Although integrate and bonus gray-scale during the surgery can both show the treatment is effective, the hints are different due to the differences between changes of gray value. There are few reports about the differences in tissue composition and component ratio. This study is focused on intramural fibroid with more that 70 percent of HIFU ablation. According to the difference of gray-scale and the signal of Magnetic Resonance Imaging, MRI for T2 Weighted Image, intramural fibroid is cataloged. The study compares the absorption of the muscular tumor after the surgery to better forecast and estimate the prognosis of fibroid and provide reference for further clinical application. As the former researches showed that MRI T2 high intensity might prompt that the fibroid had much more cellular, and the HIFU is not recommended due to the ablation has low efficiency. As a result, this study is only aimed at the fibroid of MRI T2 low and intermediate intensity.Objective:1.To analyse the influencing factors of gray-scale change in ablation.2.To observe the side sffects with different gray-scale change during and immediately after the ablation, and to evaluate the safety of different gray-scale change.3.To compare the effect of bolus gray-scale change and integrate gray-scale change on the absorption of fibroid tissue after treatment by HIFU.Methods:93 patients with 106 uterine fibroids treated by HIFU were retrospectively analyzed, patients were divided into two groups:low intensity group and intermediate intensity group. According to the change of gray-scale during HIFU ablation, and based on the signal intensity of T2-weighted magnetic resonance images patients were further divided into four groups:Group A, integrate gray-scale(MRI T2WI low signal intensity), 18 fibroids; Group B, bolus gray-scale(MRI T2WI low signal intensity),33 fibroids; Group C, integrate gray-scale(MRI T2WI equal signal intensity), 19 fibroids;and Group D, bolus gray-scale(MRI T2WI equal signal intensity),36 fibroids. To observe the side sffects with different gray-scale change during and immediately after the ablation,and calculate the average treatment intensity, treatment power and ablation rate. Patients were followed up by ultrasound examination at 1,3,6 and 12months after ablation. Relationship between fibroid shrink rate and different gray-scale were analyzed.Results:1.There existed a significant difference of fibroid volume between Group A and B, as well as between Group C and D(P<0.05).The volume of the group of integrate gray-scale was smaller than that of the group of bolus gray-scale. The volume of Group A was significantly smaller than that of Group C(P<0.05). There were no statistic differences of patients age, ablation rate, the average treatment intensity and treatment power between these four groups (.P>0.05).2.Most cases reported adverse reactions including pain in sacrococcygeal region and treatment volume, as well as skin scald and radiating ache in underbody appeared in partial patients. The pain score during the treatment ranged from 1 to 6, which released after a rest or following with a deeper sedation. Chi-square test showed no significant difference of adverse reaction among groups.2 patients in both Group B and Group D had immediate vaginal bleeding after the treatment.3 patients of Group B(9.09%) and 4 patients of Group D(11.11%) had vaginal bleeding 3 days after the treatment.3.The fibroid shrink rates between Group A and B,Group C and D at each follow-up time-point had no significant different (P>0.05).4.There was significant difference in fibroid shrink rates between Group B and Group D at 12 months follow-up(P=0.041),rrespectively are 67.86(58.53,75.66)% and 76.06(56.70,85.80)%.Conclusions:1.The large fibroids tended to appear bolus gray-scale in treatment, whose efficiency was higher than integrate gray-scale.2.The patients who appeared bolus gray-scale in ablation were more likely to have vagina bleeding than those with integrate gray-scale.It was considered to be correlated with stimulation of endometria for its difficulty to control.3.The study showed that when achieving satisfactory ablation rate, there was no obvious correlation with fibroid shrink rates and the gray-scale changes at the same follow-up time-point.4.The fibroid shrink rate in T2 equal signal intensity group was higher than that in T2 low signal intensity group, but the possibility of recurrence may be also higher. The relationship among the signal intensity of T2-weighted images, the different gray-scale and the acoustic characteristic of target tissue needed further research.