title: Early panretinal photocoagulation for ERG-verified ischaemic central retinal vein occlusion.
abstract: OBJECTIVE
  We have previously shown that photopic cone b-wave implicit time ≥ 35.0 ms in 30 Hz flicker electroretinography (ERG) predicts ocular neovascularization (NV) in central retinal vein occlusion (CRVO). Here, we evaluate the effects of early panretinal photocoagulation (PRP) in patients with ERG-verified ischaemic CRVO.
  
  
  METHODS
  Patients with CRVO, admitted to our department between 2000 and 2008, were classified as having ischaemic or non-ischaemic CRVO based on the ERG-results. In a first group of 71 patients, 18 patients had ischaemic CRVO and were assigned to standard treatment that is regular examinations and PRP as soon as NV was found. In a consecutive group of 65 patients, 18 patients with ischaemic CRVO received early PRP. In this group, ERG was performed on average 6 weeks after the first symptoms of CRVO. The patients underwent PRP as soon as possible after the ERG-examination, and the treatment was completed within one to three sessions.
  
  
  RESULTS
  Twelve patients in the standard treatment group developed neovascular glaucoma during a mean period of 5 months after the CRVO. In the early treatment group, one patient developed subtle iris rubeosis 7 months after PRP. Otherwise, none of the patients showed any signs of ocular NV, and the intraocular pressure remained within normal range, without the necessity of supplementary medication, during a mean follow-up of 41 months.
  
  
  CONCLUSIONS
  This study indicates that ocular NV in patients with CRVO can be predicted by photopic 30 Hz flicker ERG and that early PRP in ERG-verified ischaemic CRVO could be suggested as standard treatment.
authors.affiliation: Department of Ophthalmology, Haukeland University Hospital, Bergen, Norway. ole.kjeka@helse-bergen.no
authors.forename: Ole
authors.initials: O
authors.lastname: Kjeka
authors.forename: Ragnhild W
authors.initials: RW
authors.lastname: Jansson
authors.forename: Cecilie
authors.initials: C
authors.lastname: Bredrup
authors.forename: Jørgen
authors.initials: J
authors.lastname: Krohn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004596:Electroretinography; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D007511:Ischemia / Q000175:diagnosis / Q000601:surgery*; D017075:Laser Coagulation; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology; D015861:Retinal Neovascularization / Q000175:diagnosis / Q000517:prevention & control; D012169:Retinal Vein; D012170:Retinal Vein Occlusion / Q000175:diagnosis / Q000601:surgery*; D055502:Secondary Prevention; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology