title: Prevalence and causes of visual impairment and blindness in Sistan-va-Baluchestan Province, Iran: Zahedan Eye Study.
abstract: OBJECTIVE
  To determine the prevalence and causes of visual impairment and blindness in the Sistan-va-Baluchestan Province of Iran.
  
  
  METHODS
  A population-based cross-sectional study with a multistage cluster sampling technique was used to identify the study subjects. Visual acuity (VA) was defined for all participants aged >or=10 years. Participants with a VA of <20/60 were examined by an ophthalmologist to determine the causes of low vision or blindness.
  
  
  RESULTS
  5446 (84.0%) of the invited people were examined. The prevalence of visual impairment (VA <20/60) was 6.81% (95% CI 5.91% to 7.71%) and of bilateral blindness (VA <3/60) was 0.79% (95% CI 0.50% to 1.08%). Visual impairment increased with age and illiteracy. Bilateral blindness doubled in women aged >40 years. The causes of visual impairment and blindness were cataract (37.7%), corneal opacity (15.0%), amblyopia (15.0%), glaucoma (5.7%) and hyperopia (5.0%). 39.5% of the visual impairment cases were potentially curable.
  
  
  CONCLUSIONS
  The estimated magnitude of visual impairment and blindness was much higher than our expectations. Further investigation of the pattern of vision loss in women and children, particularly as a result of trachoma and amblyopia, is warranted. Implementation of measures to treat curable cases of the study population can improve the situation in the region dramatically.
authors.affiliation: Al-Zahra Eye Centre, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Hossein-Ali
authors.initials: HA
authors.lastname: Shahriari
authors.forename: Shahrokh
authors.initials: S
authors.lastname: Izadi
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Rouhani
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Ghasemzadeh
authors.forename: Ali-Reza
authors.initials: AR
authors.lastname: Maleki
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D014786:Vision Disorders / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology