肝脏激光间质热消融损伤灶的MRI-病理联系

Laser-induced interstitial thermal ablation injury in liver MRI-pathological correlation

目的探讨肝脏激光间质热消融治疗(LITT)损伤灶的MRI表现和病理改变及MRI-病理联系。方法实验兔16只,由半导体激光器(Diamed,UK)消融后,行多序列MRI扫描。观察MRI信号变化及病理改变。结果在FSET2WI序列上消融区大多表现为低信号区包绕高信号环。在其余序列上消融区表现为明显的低信号区。凝固区(Dc)与DFSE之间差异无统计学意义(P=0.970,P>0.05),并存在显著相关性(r=0.977,P<0.01);碳化区(Db)与DFE之间差异无统计学意义(P=0.581,P>0.05),并存在相关性(r=0.659,P<0.01)。结论MRI能准确测量热消融范围,并在一定程度上反映组织的病理变化,是监控LITT的有效手段。

Objective To evaluate the MRI manifestations and pathological changes of laser- induced interstitial thermotherapy （LITT） ablation injury in liver and their correlation. Methods Under the guidance of optical navigation system（iPath 200, Proview, Philips）, the livers of 16 New Zealand white rabbits（mean 3.69 kg） were performed ablation by a semiconductor laser applications （Diamed, UK）. After ablations, multi-sequences MR examination were performed, then the maximum diameter of lesions with hyposignal on the center slice were measured. After the rabbits were sacrificed, the maximum diameter of various lesions were measured macroscopically in the plane corresponding with MR slice. Results On the images of FSE T2WI sequence, most lesions demonstrated hypo-signalsurrounded by hyper-signal rim （13/16）. In the images of other sequences.the lesions demonstrated obviousl yhypo-signal. The difference between DFSE and Dc was not statistically significant （P= 0.970, P〉 0.05） and DFSE correlated closely with Dc （r = 0.977, P〈 0.01）; the difference between DFE and Db was not statistically significant（P = 0.581, P 〉 0.05）. But DFE correlated with Db（r = 0.659, P 〈 0.01） showed significant difference. Conclusion Interactive optical navigation MRI can accurately measure the size of thermal ablation, and reflect the pathological change to some extent, thus it is an effective monitoring modality in LITT.