Marfan's syndrome (MS) is an inherited disease of connective tissue. The most characteristic ocular change is dislocation of lens, but myopia and retinal detachment also can occur. We examined 11 MS patients using electroretinography (ERG). 6 cases showed normal ERG. 5 cases had abnormal ERG. One had retinal detachment. 3 had myopia and 1 case suffered from secondary glaucoma. The defects of visual function were shown by electrophysiological test in those MS patients.

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.

Tests of preoperative visual function and prediction of postoperative E chart visual acuity (ECVA) using laser interferometric visual acuity (LIVA) and electroretinogram (ERG) were performed in 16 cases (19 eyes) of cataract. The results showed that the coincident rate between preoperative LIVA and postoperative ECVA was 63.2%, and there was a parallel correlation between preoperative amplitude of photopic ERG b-wave and postoperative ECVA in 79.0% of the eyes. Comparing these two methods, the test of LIVA is very simple, fast, and is easily accepted by the patients with cataract. ERG is an objective method, which is slightly influenced by dense lens, but the test is more complex. Therefore, the combined use of these two methods will provide a more comprehensive and correct evaluation of preoperative visual function and a more reliable prediction for postoperative visual acuity in patients with cataract.