Pathogenesis of macular edema with branch retinal vein occlusion and intraocular levels of vascular endothelial growth factor and interleukin-6

Am J Ophthalmol. 2005 Aug;140(2):256-61. doi: 10.1016/j.ajo.2005.03.003.

Abstract

Purpose: To determine whether correlations between vascular endothelial growth factor (VEGF) or interleukin-6 (IL-6) contribute to the pathogenesis of macular edema in eyes of patients with branch retinal vein occlusion (BRVO).

Design: Retrospective case-control study.

Methods: Nineteen patients with macular edema with BRVO and seven patients with non-ischemic ocular disease (control group) were studied. The degree of retinal ischemia was evaluated in terms of the area of capillary non-perfusion, and the severity of macular edema was examined by optical coherence tomography. Aqueous humor samples were obtained at the time of combined vitrectomy and cataract surgery, and VEGF and IL-6 levels in aqueous humor and plasma were determined by enzyme-linked immunosorbent assay.

Results: Aqueous levels of VEGF (351 +/- 273 pg/ml) and IL-6 (7.10 +/- 6.51 pg/ml) were significantly elevated in patients with BRVO compared with the control patients (119 +/- 38.7 pg/ml and 2.27 +/- 1.11 pg/ml, respectively) (P = .0017 and P = .0052, respectively). Aqueous level of VEGF was significantly correlated with that of IL-6 (P = .0396), and aqueous levels of VEGF and IL-6 were correlated with the size of the BRVO non-perfused area (P < .0001 and P = .0331, respectively). Aqueous level of VEGF was correlated with the severity of macular edema (P = .0306).

Conclusions: VEGF and IL-6 may be involved in the pathogenesis of macular edema with BRVO. The increase in these cytokines might be used as a unique index of BRVO, through which we can determine the severity of the ischemic condition as being in a quiescent state or an exacerbation of macular edema.

MeSH terms

  • Aged
  • Biomarkers / metabolism
  • Case-Control Studies
  • Cataract Extraction
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Interleukin-6 / metabolism*
  • Macular Edema / etiology*
  • Macular Edema / metabolism
  • Male
  • Middle Aged
  • Retinal Vein Occlusion / etiology*
  • Retinal Vein Occlusion / metabolism
  • Retrospective Studies
  • Vascular Endothelial Growth Factor A / metabolism*
  • Vitrectomy
  • Vitreous Body / metabolism*

Substances

  • Biomarkers
  • Interleukin-6
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A