[The significance of preoperative visual electrophysiology for vitrectomy]

To investigate the prognostic value of preoperative visual electrophysiology in patients with vitreoretinopathy (VRP) who underwent vitrectomy.

Electroretinogram (ERG) and visual evoked potential (VEP) were performed prior to vitrectomy in 82 patients with vitreous hemorrhage or opacity due to ocular trauma, retinal detachment or retinal vascular diseases (Eales' disease, diabetic retinopathy, etc.). A comparative analysis was made of the effectiveness and visual acuities 2 weeks postoperatively.

Among the 82 eyes, the preoperative ERG was normal in 6 eyes, slightly or moderately reduced in 37 eyes and severely reduced or had no response in 39 eyes. Of these 39 eyes, no improvement or reduction in postoperative visual acuity was seen in 23 and 6 eyes respectively, a sharp contrast to the postoperative results of the 6 normal ERG eyes. The preoperative ERGs differed due to different causes. A further analysis regarding the VEP of the patients who had poor postoperative results was made.

The data showed that the preoperative visual electrophysiology was significantly correlated with the effectiveness of the operation. It is helpful in prognostic assessment of the postoperative outcome and visual acuity changes in VRP patients treated mainly by vitrectomy.