基于DTI评估子宫肌瘤HIFU治疗后对周边肌层的影响

The value of DTI in evaluation of the peripheral myometrium before and after HIFU treatment

目的比较高强度聚焦超声治疗(high intensity focued ultrasound,HIFU)子宫肌瘤后周边肌层扩散张量成像(diffusiontensor imaging,DTI)参数值,探究DTI评估HIFU治疗对周边肌层影响可行性。方法选取31例子宫肌瘤患者(42个病灶)HIFU治疗前后磁共振常规序列及DTI检查资料,记录HIFU治疗前后肌瘤周边肌层表观弥散系数(apparent diffusion coefficient,ADC)值、部分各向异性分数(fractional anisotropy,FA)值、各向异性容积比(volume ratio anisotropy,VRA)值和T2-weighted trace(T2-WT)值,重建扩散张量纤维束(diffusion tensor tractography,DTT)。配对t检验分析HIFU治疗前后肌瘤周边肌层DTI参数值变化特点。结果HIFU治疗前后肌瘤周边肌层ADC值、FA值、VRA值、T2-WT值分别为(1.92±0.41)×10-9 mm2/s、0.29±0.10、0.074±0.032、282.00±77.94;(2.01±0.52)×10-9 mm2/s、0.21±0.08、0.052±0.030、334.51±125.32。HIFU治疗后FA值和VRA值减低,T2-WT值增加,差异有统计学意义(P<0.05)。ADC值变化不大,差异无统计学意义(P>0.05)。DTT显示周边肌层纤维束减少,走行紊乱。结论DTI能够在一定程度上反映HIFU治疗对周边肌层的影响。

Objective To explore the value of diffusiontensor imaging(DTI)parameters of peripheral myometrium after high intensity focused ultrasound(HIFU)treatment of uterine fibroid.Methods Conventional MRI and DTI were carried out in 31 patients(42 lesions)with uterine fibroid.The apparent diffusion coefficient(ADC)value,fractional anisotropy(FA)value,volume ratio anisotropy(VRA)value and T2-weighted trace(T2-WT)value of peripheral myometrium were recorded before and after HIFU treatment,and diffusion tensor tractography(DTT)was rebuilt.Paired t-test was used to analyze DTI parameters.Results Before and after HIFU treatment,ADC value,FA value,VRA value and T2-WT value of peripheral myometrium were(1.92±0.41)×10-9 mm2/s,0.29±0.10,0.074±0.032,282.00±77.94;(2.01±0.52)×10-9 mm2/s,0.21±0.08,0.052±0.030,334.51±125.32.After HIFU,the FA and VRA values were decreased,and the T2-WT value was increased,the difference was statistically significant(P<0.05).There was no significant change in ADC value(P>0.05).DTT showed that the myometrial fibers were increased,the arrangement was disordered and irregular.Conclusion DTI can show the effect of HIFU treatment on peripheral muscle layer to some extent.