[Preoperative electroretinogram for predicting postoperative visual function of vitrectomy].

Vitrectomy was performed on 17 patients [19 eyes] who had dense vitreal opacity and precluding inspection of the ocular fundus. The preoperative visual acuity was light perception to 0.1, the postoperative visual acuity was 0.03 to 0.9. The preoperative electroretinogram [ERG] was tested on all patients. The correlation of the amplitudes of the ERG b-wave to the postoperative visual acuities were statistically analysed. The results showed that there was positive correlation of the amplitude of the preoperative scotopic bright ERG b-wave to postoperative visual acuity [r = 0.7709, p less than 0.01], and positive correlation of the amplitude of the preoperative photopic ERG b-wave to the visual acuity [r = 0.8086, p less than 0.01]. It suggests that the bigger amplitude of the preoperative ERG b-wave was, the better postoperative visual acuity was improved. Thus, the preoperative ERG could predict the outcome of vitrectomy in various ocular diseases with vitreal opacities and very low visual acuity.