Effects of hyperbaric oxygen therapy at different time windows after optic nerve injury in rats by F-VEP

Abstract

Objective To observe flash visual evoked potential (F-VEP)after hyperbaric oxygen (HBO) at different time points after traumatic optic nerve injury(TON) in adult rats, so as to explore the optimal time window for HBO therapy. Methods A total of 40 Sprague-Dawley rats were used to establish an optic nerve contusion model, with the left eye as the optic nerve injury eye and the right eye as the sham surgery control eye. In accordance with different HBO intervention time points of the optic nerve contusion model at 1, 3, 7 and 14 days, and the animals were divided into 5 groups, i. e. the experimental group 1, group 2, group 3, group 4 and the control group, each consisting of 8 rats. In the course of treatment, F-VEP visual changes in the 5 groups were detected at day 3, day 10 and day 20, and therapeutic effects were evaluated. Results When the detected VEP data of the optic nerve-clamped eye in all the control rats were compared with those of the sham surgical eyes, latent time was prolonged and vibration amplitude was obviously decreased, and statistical significance could be found, when comparisons were made between them (P 0.05). When compared with the F-VEP data of the control group, no statistical significance could be found in the changes of latent time and vibration amplitude for the experimental group 3 and group 4 (P>0.05). Conclusion Early HBO treatment could effectively improve F-VEP of the rats with traumatic optic nerve contusion, and after sustainment of optic nerve injury, the early the HBO intervention, the better therapeutic effects would be achieved. Key words: Optic nerve injury; Hyperbaric oxygen; Different time points; Visual evoked potential