Experimental study of rat sciatic coagulation with a novel microwave antenna / 中华物理医学与康复杂志

ABSTRACT

Objective To observe the sequential ultrastroctural and electrophysiological changes in the sciatic nerve coagulated by a newly-designed microwave antenna. Methods A total of 75 Sprague-Dawley rats were randomly divided into groups A,B and C and irradiated with microwaves at 10,20 or 30 Watts,for 6 seconds to coagulate the left sciatic nerve.Electrophysiological effects and sequential uhrastructural changes were observed on the 0th,2nd,7th,30th and 60th days after coagulation.A static sciatic index was calculated based on measurements of the footprint on the 7th,30thand 60th days after coagulation.Results On the Oth,2nd,7th and 30th days after cpagulation,the static sciatic index,the nerve conduction velocity and the amplitude of the action potentials in groups B and C had decreased significantly compared with those before coagulation.On the 60th day after coagulation.significant recovery was observed in groups A and B,but not in group C.Only mild alteration in uhrastructure was found,and only in group A.The prominent changes in uhrastructure in group B included broken Schwann cell membranes and myelin disintegration.There were severe injuries in group C,including myelin disintegration,cell deformity,coagulative necrosis,axon necrosis,basement membrane necrosis and demyelination.The structure of the sciatic nerve in group B had partially recovered after 60 days,but group C showed no recovery at all. Conclusion Microwave coagulation of a nerve can block its conduction.and even destroy the nerve.Percutaneous microwave coagulation is clinically feasible and call be an alternative treatment for pain.