Establishment of animal model of traumatic optic neuropathy and its function evaluation by F-VEP

Abstract

Background Visual electrophysiology is a sensitive index for the evaluation of visual function.It has an important value in the assessment of traumatic optic neuropathy.Rabbit is an ideal animal model of traumatic optic neuropathy,and it is simple for the record of flash visual evoked potential(F-VEP)in rabbits.ObjectiveThe present study is to establish the animal model of traumatic optic neuropathy with or without lens injury and observe the repairing procedure using F-VEP. MethodsModels of traumatic optic neuropathy associated with lens injury were established in the right eyes and only traumatic optic neuropathy were created in the left eyes of 64 healthy SPF Chinese white rabbits using fluid percussion brain injury device(FPI).F-VEP was recorded based on the Proposal of International Visual Electrophysiology on 1,2,4,7,10,14,21,28 days after injury of optic nerves.Experimental animals were sacrificed in above time points for the histopathological examination.Macrophages were labeled by ED-1 antibody and survival retinal ganglion cells (RGCs)were stained by Nissl method.Results At the first day after injury,the latencies of P_(100) in both group were longer,and the amplitudes of P_(100) in both group were lower than before injury,showing statistically significant differences among different time points(P 0.05).The duration of latency in traumatic optic neuropathy associated with lens injury group was shorter than that in only traumatic optic neuropathy group(P<0.05).The restore of latency in traumatic optic neuropathy associated with lens injury group was much faster than that in only traumatic optic neuropathy group(P<0.05).The numbers of macrophages were significantly increased and numbers of survival RGCs were considerably decreased with lapse of injury time (P<0.05).The abnormalities of VEP P_(100) and RGCs were obviously improved in 28 days after injury in both groups. ConclusionThis animal model can be established successfully by FPI.The result of retinal histopathological examination confirms F-VEP findings in this model. Key words: optic nerve injury; retina; lens; visual evoked potential; visual function