Wakabayashi Y, et al. - Researchers determined if vitreous levels of vascular endothelial growth factor (VEGF) speculated late vitreous hemorrhage (VH) after vitrectomy for proliferative diabetic retinopathy. Additionally, they examined how VEGF level altered in patients with postoperative late VH. The findings revealed that high intraocular VEGF level at primary vitrectomy served as an independent risk factor of postoperative late VH, in patients with proliferative diabetic retinopathy. A potential link was brought to light between persistent overproduction of intraocular VEGF with postoperative late VH.

Methods

• A retrospective scrutiny was performed of 85 eyes of 68 patients with proliferative diabetic retinopathy who underwent vitrectomy.
• Vitreous samples were obtained from eyes undergoing primary vitrectomy and from eyes with late VH undergoing second vitrectomy.
• An estimation was carried out of the vitreous VEGF levels, with the aid of the enzyme-linked immunosorbent assay.
• Researchers also examined the connection between VEGF level and late VH (>4 weeks) occurring during follow-up as well as clinical findings, and changes in VEGF level in eyes with late VH undergoing second vitrectomy.

Results

• The results diplayed the occurrence of late VH in 20 (24%) of 85 eyes, and 9 eyes required second vitrectomy.
• Markedly higher vitreous levels of VEGF were found (median: 1,945 pg/mL; P < 0.0001) in eyes with late VH than in those without. Furthermore, preexisting iris neovascularization (P < 0.0001), hypertension (P=0.002), and proteinuria (P=0.040) served as vital risk factors of late VH.
• A higher vitreous VEGF level illustrated an independent link with a risk of postoperative late VH in patients with proliferative diabetic retinopathy (odds ratio: 20.8, 95% confidence interval: 2.72-159.47; P=0.003), in the multivariate logistic regression analysis.
• The findings exhibited considerably lower vitreous VEGF level at second vitrectomy in patients with late VH than with that at primary vitrectomy.
• However, it remained elevated (median: 1,610 pg/mL; P=0.023).