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Updated: May 2, 2026

Optimization of the Retinal Vein Occlusion Mouse Model to Limit Variability
Published on: August 6, 2021
Intravitreal thrombin activity is elevated in retinal vein occlusion
Thomas Bertelmann1, Thomas Stief, Walter Sekundo
1aDepartment of Ophthalmology, Philipps-University bDepartment of Laboratory Medicine, Philipps-University, Marburg, Germany cDepartment of Ophthalmology, Feldkirch Regional Hospital, Feldkirch, Austria dDepartment of Ophthalmology, Goethe University, Frankfurt/Main, Germany eDoheny Eye Institute, Los Angeles, California, USA.
Intravitreal thrombin activity is elevated in eyes with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) compared to healthy controls. This finding suggests thrombin may be a new marker for blood-retina barrier breakdown in retinal vein occlusions.
Area of Science:
- Ophthalmology
- Vascular Biology
- Biochemistry
Background:
- Retinal vein occlusions (RVOs), including branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO), are common vascular diseases.
- The breakdown of the blood-retina barrier (BRB) and subsequent inflammation play crucial roles in RVO pathogenesis.
- Vascular endothelial growth factor (VEGF) is a known marker for BRB breakdown.
Purpose of the Study:
- To investigate whether intravitreal thrombin activity is elevated in eyes with BRVO and CRVO.
- To compare thrombin activity levels in RVO-affected eyes with those in healthy controls.
- To explore the correlation between intravitreal thrombin activity and VEGF levels.
Main Methods:
- Prospective case series involving 19 patients with BRVO, 13 with CRVO, and 9 healthy controls.
- Vitreous samples were collected and analyzed for thrombin activity using a chromogenic assay.
- Intravitreal VEGF levels were measured using a commercial enzyme immunoassay.
Main Results:
- Significantly higher intravitreal thrombin activity and VEGF levels were observed in eyes with BRVO and CRVO compared to controls (P=0.007 for thrombin, P=0.003 for VEGF).
- A strong positive correlation was found between intravitreal thrombin activity and VEGF levels (r=0.656, P<0.001).
- Mean thrombin activity was 1.6 ± 1.2 mIU/ml in BRVO, 2.6 ± 1.2 mIU/ml in CRVO, and 0.8 ± 0.8 mIU/ml in controls.
Conclusions:
- Elevated intravitreal thrombin activity in RVOs suggests its potential role in BRB breakdown and macular fibrin deposition.
- Intravitreal thrombin may serve as a novel biomarker for RVOs.
- Further research into direct thrombin inhibitors could offer new therapeutic strategies for RVO patients.
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