title: Computer vision syndrome: A review.
abstract: BACKGROUND
  Computer vision syndrome (CVS) is a collection of symptoms related to prolonged work at a computer display.
  
  
  OBJECTIVE
  This article reviews the current knowledge about the symptoms, related factors and treatment modalities for CVS.
  
  
  METHODS
  Relevant literature on CVS published during the past 65 years was analyzed.
  
  
  RESULTS
  Symptoms reported by computer users are classified into internal ocular symptoms (strain and ache), external ocular symptoms (dryness, irritation, burning), visual symptoms (blur, double vision) and musculoskeletal symptoms (neck and shoulder pain). The major factors associated with CVS are either environmental (improper lighting, display position and viewing distance) and/or dependent on the user's visual abilities (uncorrected refractive error, oculomotor disorders and tear film abnormalities).
  
  
  CONCLUSIONS
  Although the factors associated with CVS have been identified the physiological mechanisms that underlie CVS are not completely understood. Additionally, advances in technology have led to the increased use of hand-held devices, which might impose somewhat different visual challenges compared to desktop displays. Further research is required to better understand the physiological mechanisms underlying CVS and symptoms associated with the use of hand-held and stereoscopic displays.
authors.forename: Sowjanya
authors.initials: S
authors.lastname: Gowrisankaran
authors.forename: James E
authors.initials: JE
authors.lastname: Sheedy
mesh_terms: D016288:Computer Terminals; D034201:Computers, Handheld; D006804:Ergonomics; D005128:Eye Diseases / Q000209:etiology*; D006801:Humans; D008029:Lighting / Q000009:adverse effects; D019547:Neck Pain / Q000209:etiology*; D009784:Occupational Diseases / Q000209:etiology*; D011187:Posture; D012307:Risk Factors; D020069:Shoulder Pain / Q000209:etiology*; D013577:Syndrome
keywords: Asthenopia; visual stress; visual-ergonomics