title: Intravitreal functional plasminogen in eyes with branch retinal vein occlusion.
abstract: OBJECTIVE
  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.
authors: Department of Ophthalmology Philipps University Marburg, Marburg, Germany.
authors: Thomas
authors: T
authors: Bertelmann
authors: Walter
authors: W
authors: Sekundo
authors: Stefan
authors: S
authors: Strodthoff
authors: Michael C P
authors: MC
authors: Witteborn
authors: Thomas
authors: T
authors: Stief
authors: Sebastian
authors: S
authors: Irle
authors: Nauke
authors: N
authors: Nguyen
authors: Michael J
authors: MJ
authors: Koss
authors: Stefan
authors: S
authors: Mennel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001813:Blood-Retinal Barrier / Q000502:physiology; D002199:Capillary Permeability; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005343:Fibrinolytic Agents / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010958:Plasminogen / Q000378:metabolism*; D011446:Prospective Studies; D012170:Retinal Vein Occlusion / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: D005343:Fibrinolytic Agents; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D010958:Plasminogen