title: Prevalence and long-term natural course of retinoschisis among elderly individuals: the Copenhagen City Eye Study.
abstract: OBJECTIVE
  To characterize the prevalence and natural course of retinoschisis in a 14-year follow-up study.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  Nine hundred forty-six residents, aged 60 to 80 years, living in the Østerbro district of Copenhagen, participated in the prevalence study from 1986 to 1988. Excluding participants who died since baseline, 359 persons (97.3% of survivors) were reexamined after 14 years from 2000 to 2002. Of the 946 participants, 35 persons had prevalent retinoschisis in 1 or both eyes at baseline and 15 of these persons were alive at follow-up.
  
  
  METHODS
  Participants underwent an extensive ophthalmologic examination at Rigshospitalet, the National University Hospital of Copenhagen. Standardized protocols for the ophthalmologic examination included retinal evaluation by use of Goldmann's 3-mirror contact lens and ultrasonic B-scan of the retina. Data for the 20 persons who died were obtained from the National Patient Register and the National Central Person Register.
  
  
  METHODS
  The prevalence, presence, disappearance, and progression of peripheral retinoschisis over a period of 14 years.
  
  
  RESULTS
  The age-standardized prevalence of retinoschisis was 3.9% (95% confidence interval, 2.6-5.2) in persons aged 60 to 80 years. Gender and increasing age at baseline were not associated with the presence of retinoschisis. The retinal quadrant of maximal involvement was the inferior temporal (44.4%). One case of symptomatic progressive retinal detachment occurred during follow-up (2.2%). This was preceded by cataract surgery. Four persons developed retinoschisis in the contralateral eye during follow-up; therefore, the incidence of retinoschisis was 16% and bilaterality was 57.1% at follow-up. However, in 14 persons (73.7%) the retinoschisis remained unchanged. The disappearance rate was 8.8% (n = 4).
  
  
  CONCLUSIONS
  These findings indicate that senile retinoschisis primarily is bilateral, asymptomatic, and nonprogressive and should not be treated routinely. Cataract extraction is a possible risk factor for progressive retinal detachment.
authors.affiliation: Department of Ophthalmology, Rigshospitalet, National University Hospital, Copenhagen, Denmark. hbh@dadlnet.dk
authors.forename: Helena
authors.initials: H
authors.lastname: Buch
authors.forename: Troels
authors.initials: T
authors.lastname: Vinding
authors.forename: Niels V
authors.initials: NV
authors.lastname: Nielsen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012160:Retina / Q000000981:diagnostic imaging; D041441:Retinoschisis / Q000175:diagnosis* / Q000453:epidemiology*; D014463:Ultrasonography