AIM: To observe the effect of two kinds of bandage contact lenses on epithelial erosions and corneal thickness after vitreoretinal surgery for proliferative diabetic retinopathy(PDR).

METHODS: In this prospective, nonrandomized, comparative clinical study, 69 eyes of 69 patients with PDR were divided into two groups. They underwent vitreoretinal surgery. Group A, 36 eyes of 36 cases, the bandage contact lens with diameter of 13.8mm were covered on corneal surface during surgery under noncontact wide-angle viewing systems. Group B, 33 eyes of 33 cases, the bandage contact lens with diameter of 14.0mm were covered on corneal surface during the same surgery. Visual acuity, intraocular pressure, slit-lamp examination, corneal fluorescein sodium staining, count of corneal endothelium cells, measure of corneal thickness before and after operation were assessed.

RESULTS: Pre-operation, corneal fluorescein sodium staining positive rate was 42% in Group A and 42% in Group B(χ²=0.004, P=0.949). At 1d after surgery, the positive rate of was 47% in Group A and 45% in Group B(χ²=0.022, P=0.883). At 2d after surgery, the positive rate of was 44% in Group A and 45% in Group B(χ²=0.007, P=0.933). At 3d after surgery, the positive rate of was 44% in Group A and 42% in Group B(χ²=0.029, P=0.886). At 7d after surgery, the positive rate of was 42% in Group A and 39% in Group B(χ²=0.037, P=0.848). Count of corneal endothelium cells showed no significant difference between Group A and Group B(P>0.05). Count of corneal endothelium cells of Group A before surgery and at 7d after surgery were 2779.25±329.55 /mm², 2777.14±331.17 /mm², without significant difference(t=0.551, P=0.585); those of Group B were 2678.61±335.64/mm², 2672.45±336.25 /mm², without significant difference(t=1.774, P=0.086). Measure of corneal thickness was 519.25±23.42μm before surgery and 542.03±25.94μm after surgery in Group A(t=-6.854, P<0.001). Measure of corneal thickness was 525.64±20.97μm before surgery and 551.33±27.87μm after surgery in Group B(t=-7.204, P<0.001).

CONCLUSION: Two kinds of bandage contact lenses are used in vitreoretinal surgery in diabetic patients. The corneal epithelial integrity shows no difference before and after surgery. Both the bandage contact lens could protect the corneal epithelium and maintain good corneal transparency during vitreoretinal surgery.