[The expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy].

Objective: To explore the expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy, and to analyze the relative factors.

Methods: It was a case-control study. Data of 50 eyes of 50 PDR patients who underwent vitrectomy were retrospectively analyzed. The vitreous fluid samples were obtained during surgery. The VEGF level in vitreous fluid was determined by enzyme linked immunosorbent assay, and the expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy was analyzed. The mean follow-up was 9 months with a range from 6 to 26 months. The VEGF levels in vitreous fluid were compared between PDR patients and normal control, and silicone oil tamponade group and without silicone oil tamponade group by t-test. The changes of VEGF levels in vitreous fluid in eyes with regression, stabilization, and progression were analyzed by analysis of variance. The effects of VEGF levels in vitreous fluid on PDR were analyzed by analysis of variance.

Results: The mean VEGF level of vitreous was (592.4801 +/- 587.4267) ng/L in PDR patients, and it was (131.3022 +/- 26.9192) ng/L in normal control. VEGF level was significantly higher in PDR patients than that in normal control (t = 3.2315, P < 0.05). There were 10 eyes (20%) with progression of PDR, 10 eyes (20%) with stabilization, and 30 eyes (60%) with regression. Vitreous level of VEGF was significantly higher in eyes with progression of PDR than that in eyes with stabilization or regression of PDR (q = -3.3187, -4.0843; P < 0.05). Vitreous level of VEGF was significantly higher in eyes without retinal photocoagulation than that in eyes underwent panretinal photocoagulation or local photocoagulation (q = -4.2187, -3.9672; P < 0.05).

Conclusion: There is a correlation between the expression of VEGF of vitreous and the severity of PDR. The expression of VEGF of vitreous presents a relatively lower level in patients with stabilization and regression of PDR.