Analyzing the relationship between eigenvalues and limb function of rabbit after traction inj ury / 实用放射学杂志

ABSTRACT

Objective To investigate the correlation between eigenvalues(λ∥ andλ⊥)of sciatic nerve and limb function in a rabbit model of acute nerve traction inj ury for finding the role ofλ∥ andλ⊥ on diagnosis of nerve inj uries.Methods The right sciatic nerves of 32 Newland rabbits were selected to be performed as traction injury,and then left sciatic nerves were treated as control for the sham operation side.MRI DTI scan was performed before and after the operation on 1 day ,3 day,and 1 week,2,3,4,6 and 8 weeks respectively.Theλ∥ andλ⊥ of inj ured sciatic nerves and sham operated nerves were measured,meanwhile functional exami-nations were evaluated,and then analyzing the correlation betweenλ⊥ of inj ured sciatic nerves and the score of inj ured limb function in the periods of 3 days to 8 weeks;finally different portions of sciatic nerve were removed for histological examinations.Results Theλ⊥ of inj ured sciatic nerves in the proximal portion was slightly increased at 3 days and recovered to the normal at 2 weeks.Theλ⊥ of inj ured sciatic nerves in the traction portion and distal portion were slightly raised at 1 day,reached to its maximum value at 3 days,and then decreased gradually after 1 week and dropped to the pre-operation level after 4 weeks.Theλ⊥ of inj ured sciatic nerves in the proximal portions was significantly higher than that of the sham-operated nerves from 1 day to 1 week(F=7.275,P=0.000). Theλ⊥ of inj ured sciatic nerves in the traction portion and distal portion were significantly higher than that of the sham-operated nerves from 1 day to 3 weeks(F=5.851,F=3.794,P=0.001,P=0.000).However,there was no significantly difference between theλ∥ of inj ured nerves in each portion and sham-operated nerves .The negative correlation between theλ⊥ of inj ured sciatic nerves in the distal portion and the score of the nerve function in the injured limb was found (r=-0.938,r=-0.897,P<0.01).Conclu-sion Theλ⊥ of inj ured nerves in the traction portion and distal portion could monitor the process of degeneration and regeneration of sciatic nerve in traction inj ury,while theλ∥ plays no obvious role in diagnosis of nerve inj uries.