脉冲射频术与射频热凝术对兔股神经的影响

Influences of Pulsed Radiofrequency and Radiofrequency Hyperthermia on Rabbit Femoral Nerve

目的研究脉冲射频术(PRF)与射频热凝术(RFTC)对兔股神经及周围组织的影响,以指导临床疼痛治疗.方法健康家兔20只,随机分为5组,每组4只,均分离双侧股神经,分别采用PRF及不同热凝温度的RFTC对股神经进行治疗.T42组(温度42℃,时间120 s,脉冲频率2 Hz),T42'组(同T42组,重复1次),T50组(温度50℃,时间120 s),T70组(温度70℃,时间120 s),T80组(温度80℃,时间120 s).5组射频治疗后均取股神经作光镜检查.结果光镜下,T42组大部分神经束结构完整,仅局部少量神经束外膜轻度热凝性破坏;T42'组可见局部神经束外膜热凝性破坏;T50组可见神经束外膜局灶性热凝性破坏,神经纤维束局灶性外膜不完整;T70、T80组均见外膜及神经纤维热凝性变性、坏死并出现断裂现象,神经纤维的髓鞘和轴索结构完全破坏.结论 RFTC严重破坏神经及周围组织,导致毁损性损伤;而PRF对神经及周围组织损伤轻微,较RFTC安全、重复性高.同时证明RFTC的镇痛作用是通过破坏神经实现的.

Objective To study the influences on femoral nerve and its surrounding tissue of pulsed radiofrequency（PRF）and radiofrequency hyperthermia（RFTC）.Methods Twenty rabbits were selected and randomly divided into 5 groups（4 rabbits in each group）.The PRF was applied to the femoral nerve of rabbits in the PRF group at 42 ℃ for 120 s（T42 group） with the pulsed frequency of 2 Hz and T42 group repeat the same steps as T42 group.The RFTC was respectively used to the same tested part of rabbits in the RFTC group at 50 ℃（T50 group）,70 ℃（T70 group）and 80 ℃（T80 group）for 120 s.The femoral nerve of rabbits was removed for pathological examination under optical microscope.Results In T42 group,lots of nerves of rabbits were undamaged under optical microscope,only a little heat damage presented on some nerve envelope.Partial heat damage also occurred in T42 group.Focal hot damage of nerve envelop was found in T50 group.Heat destroys,putrescence and fragmentation of nerve envelop and nerve tract were detected,and myelin sheath and axonal injury were discovered in T70 and T80 group.Conclusions The serious permanent damage of nerves and surrounding tissues is induced by RFTC.PRF causes slight body lesion and is a new safer treatment method for pain than RFTC.The tested results indicate that the analgesic effect of RFTC is achieved by damaging nerves.