title: The natural history of occult choroidal neovascularisation associated with age-related macular degeneration. A systematic review.
abstract: BACKGROUND
  The purpose of this review is to combine the results of existing literature on the natural history of occult choroidal neovascularisation (CNV) associated with age-related macular degeneration (AMD).
  
  
  METHODS
  Published reports evaluating eyes with occult CNV in AMD patients were selected for meta-analysis based on a computerised MEDLINE search. Pooled estimates of the proportions of eyes with a vision loss greater than 2 to 3 (moderate vision loss) or 6 lines (severe vision loss) at 1 year and 2 to 3 years, respectively, or developing a classic component on fluorescein angiography at 1 year were measured.
  
  
  RESULTS
  There is no significant heterogeneity among published rates of visual loss and development of classic CNV. The overall pooled estimates (95% confidence limits) of the proportions of eyes with at least moderate or severe vision loss, respectively, were 59% (53% to 64.5%) and 34% (25% to 43%) at 1 year and 70% (64% to 76%) and 47% (40% to 54%) at 2 to 3 years; the overall pooled estimate of the percentage of eyes developing classic CNV at 1 year was 46% (39% to 54%).
  
  
  CONCLUSIONS
  A substantial number of patients with occult CNV from AMD will develop at least moderate visual loss at 1 year and severe visual loss within 3 years. However, visual acuity may remain stable in up to 30% of patients. These results may help us to understand the exact role of new therapies and in planning future trials.
authors.affiliation: Department of Ophthalmology, University of Udine, Udine, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Polito
authors.forename: Miriam
authors.initials: M
authors.lastname: Isola
authors.forename: Paolo
authors.initials: P
authors.lastname: Lanzetta
authors.forename: Dario
authors.initials: D
authors.lastname: Gregori
authors.forename: Francesco
authors.initials: F
authors.lastname: Bandello
mesh_terms: D020256:Choroidal Neovascularization / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D008268:Macular Degeneration / Q000150:complications* / Q000503:physiopathology; D015354:Vision, Low / Q000209:etiology