title: [The study on binocular visual field summation and its possible mechanism].
abstract: OBJECTIVE
  To observe the summation effect of binocular visual field in persons with normal or abnormal visual field and study the validity of four kinds of theory (best eye, average eye, best location, binocular summation) on binocular visual field formation.
  
  
  METHODS
  The monocular and binocular visual field were tested in 15 cases with normal visual field and 58 cases of different kinds of ocular diseases with abnormal visual field.
  
  
  RESULTS
  The mean rates of summation in normal visual field group and abnormal group were 93.00% and 93.10% respectively with no significant difference (P > 0.05). The mean degree of binocular visual field summation of normal visual field group was 7.05. The abnormal group had a greater variation of summation degree than that of normal group. The comparison of four theoretic simulating mathematical methods with the tested mean retinal sensitivity (MS) of binocular visual field in both groups showed minimum difference between the MS calculated by the model of best location and the actual MS value.
  
  
  CONCLUSIONS
  Binocular summation is a common vision phenomena. In the four kinds of theory on binocular visual field formation, the model of best location can best reveal the phenomena of binocular visual field summation.
authors.affiliation: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
authors.forename: Guangwei
authors.initials: G
authors.lastname: Luo
authors.forename: Futian
authors.initials: F
authors.lastname: Jiang
authors.forename: Jiongji
authors.initials: J
authors.lastname: Liang
authors.forename: Caijiao
authors.initials: C
authors.lastname: Liu
authors.forename: De-Zheng
authors.initials: DZ
authors.lastname: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005128:Eye Diseases / Q000175:diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015348:Vision, Binocular / Q000502:physiology*; D014792:Visual Acuity; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields / Q000502:physiology*; D014796:Visual Perception