摘要目的 探讨图形视觉诱发电位(P-VEP)对隐匿型间接视神经损伤早期诊断的价值.方法 对17例(17眼)早期无明显视力下降的眼部或颜面部外伤患者伤后48 h内、1个月、2个月、3个月行P-VEP检测,以自身对侧健眼作为对照,观察其P100波的振幅及峰时,获取生物学统计指标进行分析.结果 17眼伤后48 h内P-VEP检查结果表现为P100波振幅降低,与自身对侧健眼比较,振幅差异有统计学意义(P＜0.05).P100波峰时正常或稍延迟,与自身对侧健眼比较无统计学意义(P＞0.05).伤后1个月、2个月、3个月P100波振幅降低和峰时延迟加重,与自身对侧健眼比较有统计学意义(P＜0.05).结论 P-VEP检查能客观地反映视神经的损伤,能为隐匿型间接视神经损伤的早期诊断、判定视功能、估计预后等方面提供客观依据.其表现为早期振幅降低为主,随后方为峰时延迟.

abstractsObjective To investigate the early diagnostic value of the pattern visual evoked potential(P-VEP) applied in patients with occult indirect optic nerve injury.Methods P-VEP examination was conducted in 17 patients(17 eyes)without decreased vision in early stage within 48 hours,1 month,2 months,3 months after the eye or facial injury,and the opposite healthy eyes were taken as control.The P100 amplitude and latency were observed to obtain the biological statistics indexes which were analyzed.Results The results of P-VEP examination showed that the amplitude of P100 was decreased within 48 hours,and the difference in amplitude of P100 was statistically significant between the injury eyes and the opposite healthy eyes(P ＜0.05).The latency of P100,however,was normal or slightly extended compared with that of the opposite eyes and the difference was not statistically significant (P ＞ 0.05).The decrease of amplitude and the delay of latency of P100 at 1 month,2 months and 3 months after the injury were more serious than that at 48 hours after the injury and compared with the opposite healthy eyes,the difference was statistically significant (P ＜ 0.05).Conclusion P-VEP can sensitively reflect the damage of the optic nerve,and can provide the objective basis for the early diagnosis and the evaluation of the visual function and prognosis of occult indirect optic nerve injury.The main performance in the early stage was the decrease of the amplitude followed by the delayed latency.