Sciatic nerve traction injury in rabbits: Comparative study on magnetization transfer imaging and pathology

Objective To investigate the pathological basis of the magnetization transfer ratio(MTR) changes of rabbit's sciatic nerve after traction injury.Methods MR examination was performed before and 1 day,3 days,1,2,3,4,6,8 and 10 weeks after traction injury of sciatic nerve in 20 rabbits.The injured segment,the proximal and distal segments of the sciatic nerves were obtained for light microscopic and electric microscopic examination.Results After injury,the MTR values of sciatic nerve descended obviously in earlier stage,and then gradually rose later.After injury,the sciatic nerve mainly manifested inflammation reaction and degeneration,including myelin disaggregation and axon lost in the early stage,exhibited Schwann cell proliferation and nerve fiber regeneration in the later stage.Differences of MTR values were dependent on the site along the same injured nerve,with the most pronounced of MTR values descended observed in the most severely damaged portion of the injured nerve.Conclusion After traction injury of rabbit's sciatic nerve,the change of MTR can reflect the pathological change and the severity of injury,therefore can be regarded as assistant index for prognostic and therapeutic evaluation.