活体猪肢体长骨多极射频消融灶的影像改变

Imaging Features Following Multi-polar Radiofreqency Ablation in Long Bones of Swine Limbs

目的通过对活体猪胫骨近端骨端及骨干行经皮射频消融(RFA),观察RFA灶于RFA后不同时间点的影像学及其病理改变。材料与方法 11头活猪行RFA,处死前行X线及CT检查;共获取骨端及骨干组织对照标本、RFA后0～84d中的7个时间点骨端及骨干标本,并进行病理检查。结果骨端多极RFA灶影像改变始于边缘,X线及CT检查均显示为低密度骨质吸收带,并向内逐渐扩展至中心,骨痂形成于低密度的外缘,并向内缓慢填充。骨干多极RFA灶CT检查最早显示为髓质内低密度区,且与RFA灶镜下坏死区相对应,X线及CT检查均显示其外缘内、外骨痂形成,内骨痂并向内逐渐填充至髓腔缩小。多极RFA后21～35d,X线及CT检查均见骨干病理性骨折。结论 X线及CT图像能够反映RFA灶的坏死范围、随后的吸收及周围组织修复过程的特点,可以为骨肿瘤RFA灶的损毁情况及周围组织修复过程的评估提供影像学参考。

Purpose To observe the imaging and pathological changes of lesions following multi-polar radiofrequency ablation （RFA） of tibia bones in swine at different time points. Materials and Methods Eleven swines underwent RFA. X-ray and CT examination were performed before sacrificing the experimental swine. Specimens were obtained at seven time points from 0 to 84 days for pathological examination. Results Imaging changes on X-ray and CT of epiphysis lesions following ablation started with low density areas of bone absorption in the edge and extended to the center. The callus tbrmed in the edge of the lesions and slowly grew inwards. Imaging changes of diaphysis lesions on CT were reduced bone marrow density corresponding to microscopic necrotic area. Callus formation was similar to epiphysis lesions with decrease in medullary cavity. Pathological fractures were observed from 21 days to 35 days after RFA on X-ray and CT. Conclusion X-ray and CT examinations can demonstrate necrosis and characteristics of bone absorption and repairing process, and are helpful in evaluating effect of RFA.