title: Aqueous vascular endothelial growth factor and endothelin-1 levels in branch retinal vein occlusion associated with normal tension glaucoma.
abstract: OBJECTIVE
  To evaluate aqueous levels of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) in patients with branch retinal vein occlusion (BRVO) with and without normal tension glaucoma (NTG), and to assess the therapeutic efficacy of intravitreal bevacizumab (IVB) in these patients.
  
  
  METHODS
  Sixteen eyes with NTG of 48 age and sex-matched eyes without NTG that had previously received IVB for BRVO were followed for 6 months. Aqueous VEGF and ET-1 levels were measured by enzyme-linked immunosorbent assay at the time of baseline IVB. Logarithm of the minimum angle of resolution best corrected visual acuity (BCVA) and central macular thickness (CMT) were measured at baseline and then at 1, 3, and 6 months postinjection.
  
  
  RESULTS
  The obstruction site of BRVO was closer to the optic disk in eyes with NTG compared with controls (P=0.001). Baseline BCVA, CMT, and VEGF levels were similar between the 2 groups. Baseline ET-1 levels were significantly higher in eyes with NTG than those without NTG (P=0.009). After IVB, there was a significant improvement in both BCVA and CMT at 6 months, irrespective of the presence of NTG. However, BCVA in the presence of NTG was significantly worse at 6 months compared with eyes without NTG even though CMT was similarly reduced in both groups (P=0.04).
  
  
  CONCLUSIONS
  Aqueous VEGF levels are similar in patients with BRVO with or without NTG, whereas aqueous ET-1 levels are elevated in the presence of NTG. Although IVB may be effective in the treatment of BRVO, the presence of NTG may limit visual recovery despite anatomic recovery of CMT.
authors.affiliation: Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Seoul, South Korea.
authors.forename: Bum Ho
authors.initials: BH
authors.lastname: Sin
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Song
authors.forename: Sung Pyo
authors.initials: SP
authors.lastname: Park
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D001082:Aqueous Humor / Q000378:metabolism*; D000068258:Bevacizumab; D019332:Endothelin-1 / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D058449:Intravitreal Injections; D057066:Low Tension Glaucoma / Q000378:metabolism*; D008269:Macular Edema / Q000188:drug therapy / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012170:Retinal Vein Occlusion / Q000188:drug therapy / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D014792:Visual Acuity / Q000502:physiology
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D019332:Endothelin-1; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab