子宫肌瘤超声消融与MRI信号特征关系的研究

MR image features of uterine fibroids after ultrasound ablation:report of 80 fibroids

目的探讨超声消融子宫肌瘤后磁共振信号变化的特征。方法65例患者共80个肌瘤在超声消融前1周及消融后4～8周行MRI检查,比较消融区消融前后T1加权/T2加权信号变化。结果增强扫描:治疗前灌注率98.8%(79/80),治疗后灌注率8.8%(7/80)。T1加权:消融前高、等、低信号分别占1.2%、91.3%和7.5%;消融后依次占83.8%、16.2%、0;消融后高信号肌瘤消融率100%(67/67),等信号肌瘤消融率46.2%(6/13),消融率差异显著(P<0.05);信号变化(均变成高信号)66个肌瘤,消融率100%(66/66),信号不变14个肌瘤,消融率50%(7/14),消融率差异显著(P<0.05)。T1加权高信号区域体积与消融体积直线相关(r=0.93,P<0.05)。T2加权信号变化与消融没有明显相关性(P>0.05)。结论超声消融子宫肌瘤后早期MRI的T1加权高信号,可成为判断肌瘤出现凝固性坏死的标准之一。

Objective To explore the signal characteristics of MR imaging after ultrasound ablation for uterine fibroids. Methods Totally 65 patients （41.2 ± 6.5 years old, before menopause） with 80 uterine fibroids who were admitted in our hospital from January 2007 to February 2008 were subjected in this study. They received MR imaging 1 week before and 4 to 8 weeks after ultrasound ablation. T1-weighted/T2-weighted signals before and after the therapy were compared. Results The filling rate was 98.8% （79/80） before therapy, but 8.8% （7/80） after therapy on contrast-enhanced scanning. Before therapy on T1-weighted scanning： high-signal 1.2%, intermediate-signal 91.3%, low-signal 7.5% ; after therapy 83.8%, 16.2% and 0 in turn ; high-signal fibroids 100% （ 67/67 ） showed necrosis ; intermediate-signal fibroids 46.2% （ 6/13 ） showed necrosis（ P 〈 0.05 ） ; signal of 66 fibroids increased to high-signal, and 100% （67/67） showed necrosis. Signal of 14 fibroids had no change, and 50% （7/14） showed necrosis （ P 〈 0. 05 ） ; relationship of volume between high-signal area on T1-weighted and necrosis area had linear correlation （ r =0. 93, P 〈 0. 05）. There was not obviously relationship between change of signal of T2-weighted and necrosis （P 〉 0. 05 ）. Conclusion High-signal of MR T1-weighted imaging indicates coagulation necrosis of the fibroids in early period after ultrasound ablation.