Intravitreal Functional Plasminogen in Eyes with Branch Retinal Vein Occlusion

Abstract

Purpose: To evaluate whether intravitreal functional plasminogen is elevated in eyes with branch retinal vein occlusion (BRVO) and to discover whether intravitreal plasminogen activities are correlated with the extent of blood-retina barrier (BRB) breakdown. Methods: Our study is a prospective case series of 20 consecutive patients with BRVO and 10 consecutive patients serving as controls. Vitreous taps were extracted from the central vitreous body and plasminogen was functionally determined in an innovative, ultrasensitive p-nitroanilide reaction after activation with streptokinase (100% of normal, %N = functional plasminogen in pooled normal citrated plasma). Intravitreal VEGF levels were assayed to estimate BRB breakdown. Results: Intravitreal functional plasminogen was detected in all analyzed samples (n = 30) and mean (±SD) plasminogen activities were found to be 0.97 ± 1.06%N (range: 0.03-3.9%N). Patients suffering from BRVO exhibited significantly higher intravitreal plasminogen (1.35 ± 1.11%N) in comparison with controls (0.20 ± 0.21%N, p < 0.001). Intravitreal VEGF concentrations in the BRVO group (576 ± 547 pg/ml) were significantly higher than these in controls (111 ± 120 pg/ml, p = 0.003). There was a significant correlation between intravitreal functional plasminogen and intravitreal VEGF levels (r = 0.519, p = 0.003). Conclusions: Intravitreal functional plasminogen is significantly elevated in eyes suffering from BRVO and correlates with the extent of BRB breakdown. The induction of posterior vitreous detachment by using intravitreally administered recombinant tissue plasminogen activator (enzymatic vitreolysis) should be explored in further investigations.

The impact of posterior vitreous adhesion on ischaemia in eyes with retinal vein occlusion

“…; Bertelmann et al. , ,b,c, ). For patient management, it is of notably importance to distinguish between ischaemic‐ and non‐ischaemic‐typed RVO, because the ischaemic variant can cause severe and irreversible damage to the eye (Rogers et al.…”

“…; Bertelmann et al. , ,b,c, ) could be of benefit to hamper neovascular intricacies. Whereas ppV is an invasive surgical procedure (Tachi et al.…”

“…) might advance into the retina specialists’ armamentarium for PVD induction in the future (Bertelmann et al. , ,b,c, ). This in turn might offer the chance to reduce the amount and extension of tissue‐destructing (pan‐) retinal laser photocoagulation (Sebag et al.…”

“…Previous reports indicate that posterior vitreous attachment (PVA) is a risk factor for the development of retinal vein occlusion (RVO) (Bertelmann et al. , ,b,c, ). PVA furthermore promotes development, severity and chronicity of RVO‐induced macular oedema (Kado et al.…”

Proteins involved in focal adhesion signaling pathways are differentially regulated in experimental branch retinal vein occlusion

“…Bertelmann et al (2014) recently found functional plasminogen to be 6e7 fold higher in vitreous taps from patients with BRVO compared to controls. The study also identified intravitreal functional plasminogen to correlate with VEGF.…”