弱视治愈儿童图形视觉诱发电位的观察分析

目的: 通过观察比较已治愈弱视患儿与正常视力儿童的图形视觉诱发电位(pattern visual evoked potential, P-VEP), 寻求一种客观评价儿童视功能及预测弱视疗效的手段, 并且进一步观察影响P-VEP的相关因素, 为进一步探讨弱视的发病机制提供临床依据。方法: 将60例 8~12岁经正规弱视治疗后弱视治愈儿童分为单眼弱视治愈组(40人, 弱视治愈眼40只, 而另眼为相对正常眼40只)及双眼弱视治愈组(20人40只眼)。20例视力正常的同龄儿童为正常对照组。比较3组P-VEP的潜伏期和振幅, 并通过线性回归分析影响P-VEP的相关因素。结果: 3组双眼矫正视力比较差异均无统计学意义(P>0.05)。单眼弱视治愈组及双眼弱视治愈组的弱视眼P100 波较正常组潜伏期延长、振幅降低;其中单眼弱视治愈组弱视眼明显低于双眼弱视治愈组。单眼弱视治愈组的相对正常眼P100 波较正常组潜伏期延长、振幅降低, 而与双眼弱视治愈组比较差异无统计学意义(P>0.05), 与自身弱视眼比较P100 波潜伏期缩短、振幅增加(P<0.05)。线性回归分析结果显示影响弱视眼P100 潜伏期的主要相关因素是初治矫正视力、初治年龄及屈光度。结论: 通过弱视治疗, 虽然患儿视力恢复正常, 但弱视眼及相对正常眼的视功能仍未恢复正常;初治矫正视力、初治年龄及屈光度对患儿视力及视功能恢复均有重要影响;仅针对增加视力的传统弱视治疗对于提高双眼视功能仍有不足。

Pattern visual evoked potentials in normal-vision eyes of post-therapy amblyopia

Objective: To evaluate the clinical significance of pattern visual evoked potential (P-VEP) parameters on amblyopic patients with normal-vision after pleoptic therapy.
Methods: We investigated 60 amblyopic children (8–12 years old) who gained normal-vision after pleoptic therapy. These patients were assigned to a unilateral amblyopia group (40 patients) and a bilateral amblyopia group (20 patients). Another 20 healthy children served as a control group. All patients underwent a full initial ophthalmologic and orthoptic evaluation. P-VEP test was performed in all. Amplitude and latencies were analyzed and compared among groups. The latencies of P100 waves in the amblyopic eyes were used to generate a multiple linear regression formula from sex, first treatment age, baseline visual acuity, and cycloplegic refraction.
Results: There was no significant difference in the mean levels of best-corrected visual acuity among groups (P>0.05). A significant prolongation of the latency and a decrease of amplitude of P100 waves were observed in the unilateral amblyopia group and the bilateral amblyopia group compared with the healthy control group (P<0.05). Amplitude and latencies of the fellow eyes in the unilateral amblyopia group were abnormal compared with the healthy control group (P<0.05). Multiple linear regression analysis revealed that the latencies of P100 waves were significantly correlated with the first treatment age, baseline visual acuity, and cycloplegic refraction (R²=0.52, P<0.05).
Conclusion: Deficits exist in the fellow eyes and in normal-vision eyes after pleoptic therapy. The delayed P100 latency is affected by the first treatment age, baseline visual acuity, and cycloplegic refraction. Traditional amblyopic therapy may be not enough for vision function recovery.