title: Prophylactic treatment of age-related macular degeneration report number 2: 810-nanometer laser to eyes with drusen: bilaterally eligible patients.
abstract: OBJECTIVE
  To determine the prophylactic and therapeutic value of a single subthreshold 810-nanometer laser treatment in patients with high risk drusen as a manifestation of dry age-related macular degeneration in both eyes.
  
  
  METHODS
  The Prophylactic Treatment of Age-related Macular Degeneration study enrolled 1,278 eyes of 639 participants who were 50 years or older with at least 5 drusen 63 microm or more in diameter in each eye. Treatment consisted of the placement of an annular grid of 48 extrafoveal, subthreshold 810-nm diode laser applications centered at but sparing the foveola in one eye of each participant, with the fellow eye serving as a control. Development of choroidal neovascularization and change in best-corrected visual acuity were compared between treated and untreated eyes.
  
  
  RESULTS
  Subthreshold laser treatment did not decrease the incidence of choroidal neovascularization in treated versus untreated eyes. A modest visual acuity benefit in treated eyes was found at 24 months (1.5 letter difference; P = .04) and in the treated eyes of participants with a baseline visual acuity between 20/32 and 20/63 (4.0 letter difference; P = .0034). However, this treatment effect was not sustained at 3 years.
  
  
  CONCLUSIONS
  A single subthreshold 810-nanometer laser treatment to eyes of participants with bilateral high risk drusen is not an effective prophylactic strategy against choroidal neovascularization.
authors.affiliation: UPMC Eye Center, University of Pittsburgh, PA 15213, USA.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Friberg
authors.forename: Peter M
authors.initials: PM
authors.lastname: Brennen
authors.forename: William R
authors.initials: WR
authors.lastname: Freeman
authors.forename: David C
authors.initials: DC
authors.lastname: Musch
mesh_terms: D000368:Aged; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D007839:Functional Laterality; D005654:Fundus Oculi; D006801:Humans; D015994:Incidence; D017075:Laser Coagulation; D008268:Macular Degeneration / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D015593:Retinal Drusen / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D014792:Visual Acuity