title: Characteristics of choroidal neovascularization in the complications of age-related macular degeneration prevention trial.
abstract: OBJECTIVE
  To describe the characteristics of incident choroidal neovascularization (CNV) in observed and treated eyes in the Complications of Age-related Macular Degeneration Prevention Trial (CAPT).
  
  
  METHODS
  Cross-sectional descriptive study within a multicenter, randomized clinical trial.
  
  
  METHODS
  Patients who developed CNV during CAPT follow-up.
  
  
  METHODS
  Inclusion criteria for CAPT specified bilateral large drusen (>or=10 drusen at least 125 micro), visual acuity >or=20/40 in each eye, and age >or=50. Exclusion criteria included CNV and geographic atrophy >1 Macular Photocoagulation Study (MPS) disc area or within 500 micro of the foveal center. One eye of each person was selected randomly for low-intensity laser treatment and the contralateral eye was observed. Fluorescein angiography was performed at baseline, annually for >or=5 years, and whenever there were symptoms of CNV. Trained readers at the CAPT Photograph Reading Center assessed color stereo photographs and angiogram negatives to identify CNV.
  
  
  METHODS
  Choroidal neovascularization was classified by type (predominantly classic CNV, minimally classic CNV, occult only CNV, or scar), location, and area. Visual acuity was measured by certified examiners. Symmetry of characteristics between eyes of bilaterally affected patients was examined.
  
  
  RESULTS
  Choroidal neovascularization developed in 282 eyes of 225 patients. At the time of detection, 192 (68%) of the lesions were occult only, 153 (54%) were subfoveal, and 157 (56%) were <or=2 MPS disc areas. Visual acuity was >or=20/40 in 123 (69%) of 179 eyes with visual acuity measured at the time of detection. Choroidal neovascularization developed in both eyes in 57 patients (25%) during CAPT follow-up. Lesions in eyes of bilaterally affected patients were no more similar to each other than affected eyes in 2 different patients.
  
  
  CONCLUSIONS
  When patients are monitored closely, many CNV lesions can be detected outside of the fovea and when they are relatively small. Early detection may lead to improved long-term visual acuity.
authors.affiliation: Department of Ophthalmology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104-3309, USA.
authors.forename: Maureen G
authors.initials: MG
authors.lastname: Maguire
authors.forename: Judith
authors.initials: J
authors.lastname: Alexander
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Fine
mesh_terms: D020256:Choroidal Neovascularization / Q000145:classification / Q000175:diagnosis* / Q000209:etiology* / Q000517:prevention & control; D003430:Cross-Sectional Studies; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D006801:Humans; D017075:Laser Coagulation; D008268:Macular Degeneration / Q000150:complications*; D010781:Photography; D015203:Reproducibility of Results; D014792:Visual Acuity