Intravitreal Bevacizumab and Cytokine Levels in Major and Macular Branch Retinal Vein Occlusion

Abstract

Purpose: My aim was to evaluate the effect of intravitreal bevacizumab and to determine the concentrations of inflammatory cytokines in patients with macular edema due to branch retinal vein occlusion (BRVO), according to the site of the occlusion. Methods: In a prospective interventional case series, 46 eyes of patients with macular edema due to major (n = 30) or macular BRVO (n = 16) were included. The patients were treated primarily with intravitreal bevacizumab (1.25 mg/0.05 ml) and completed 12 months of follow-up. Reinjections were performed if optical coherence tomography showed persistent or recurrent macular edema. Aqueous humor samples were collected at the time of initial intravitreal injection. Multiplex bead assays were used for the measurement of cytokines. Results: The visual acuity and central macular thickness were improved significantly in patients with major and macular BRVO at 12 months. During 12 months, the eyes with major BRVO received a mean of 3.8 intravitreal injections, whereas those with macular BRVO received a mean of 1.9 intravitreal injections (p = 0.009). Significantly increased concentrations of IL-6, IL-8 and MCP-1 were observed in the aqueous humor of BRVO patients compared with control samples. Higher concentrations of IL-6, VEGF, PDGF-AA and MCP-1 were measured in the aqueous humor of patients with major BRVO compared with macular BRVO at baseline (p < 0.05). Conclusion: Intravitreal bevacizumab was similarly effective for improving macular edema in patients with major and macular BRVO. However, macular BRVO required fewer injections and had lower cytokine levels in the aqueous humor than major BRVO.

Intravitreal Ranibizumab and Aqueous Humor Factors/Cytokines in Major and Macular Branch Retinal Vein Occlusion

“…These findings are in agreement with the report by Lim [5], and may be related to the difference in the extent of retinal involvement between the two groups. We also found that the aqueous humor levels of sVEGFR-1 and PlGF were significantly higher in the major BRVO group than in the macular BRVO group.…”

“…In contrast, macular BRVO is unlikely to be associated with neovascularization because a smaller area of the retina is affected, but macular edema and visual impairment develop frequently [4]. Lim [5] reported that treatment of macular BRVO required fewer doses of intravitreal bevacizumab than major BRVO and was associated with a lower level of vascular endothelial growth factor (VEGF) in the aqueous humor. We have also reported that the level of VEGF in the vitreous fluid was lower in macular BRVO than in major BRVO [6].…”

Three intravitreal bevacizumab versus two intravitreal triamcinolone injections in recent-onset branch retinal vein occlusion

“…We also noted that the differences between the drugs in BCVA and CMT changes were more prominent in the ischemic type of BRVO. It has been shown that VEGF is a key factor for macular edema in retinal vein occlusion [20,21], Therefore, inhibition of VEGF should theoretically offer a therapeutic benefit for BRVO. This effect has been shown with anti-VEGF drugs such as bevacizumab [8][9][10][11][12][22][23][24], ranibizumab [25,26], and pegaptanib [27] in terms of both VA improvement and CMT reduction.…”

Inflammatory Factors in Major and Macular Branch Retinal Vein Occlusion

“…Vascular damage due to extension of the zone affected by venous occlusion is accompanied by complex cellular changes and an inflammatory response. Lim et al reported that macular BRVO required less treatment and was associated with lower levels of inflammatory factors in the aqueous humor than major BRVO [5]. However, little is known about the influence on inflammatory factors in the vitreous fluid of the site of occlusion causing BRVO.…”