Application of visual electrophysiology in evaluation of visual function in patients with severe chemical eye injury

Objective To explore the correlation between the results of preoperative flash visual evoked potentials (FVEP),flash electroretinography (FERG) and postoperative visual acuity for patients with severe chemical eye injury requiring artificial corneal implant surgery. Methods Of the 32 patients (32 eyes) who had undergone artificial corneal transplantation due to severe chemical ocular injury in our hospital from October 2016 to October 2019,there were 27 males and 5 females aged 20-60 years.The correlation between the best corrected visual acuity (BCVA) after operation and the results of preoperative FVEP,FERG and their joint examination were analyzed. Results All patients had successfully completed artificial corneal implant surgery.Their preoperative vision was evaluated as light perception or finger count,while the postoperative best corrected visual acuity ranged from 0.05 to 0.8,including 0.6 in 14 eyes (14/32,44%),0.3-0.5 in 10 eyes (10/32,31%),0.05-0.25 in 7 eyes (7/32,22%),and <0.05 in 1 eye (1/32,3%).The preoperative detection result of FVEP combined with FERG was normal in 2 eyes (2/32,6.2%) while abnormal in 30 eyes (30/32,93.8%),including 10 eyes with mild decreasing,11 eyes with moderate decreasing,6 eyes with severe decreasing,and unrecordable in 3 eyes.Preoperative FVEP,FERG and FVEP combined with FERG were all positively correlated with the postoperative best corrected visual acuity (r=0.674,P=0.000;r=0.659,P=0.000;r=0.793,P=0.000). Conclusion FVEP,FERG,especially the combination of FVEP and FERG is helpful for predicting the visual function before artificial corneal inplantation in patients with severe chemical eye injury,and it is worthy of clinical generalization.