title: Patterns of Binocular Visual Field Loss Derived from Large-Scale Patient Data from Glaucoma Clinics.
abstract: OBJECTIVE
  To estimate prevalence of visual field (VF) loss in superior and inferior hemifields in binocular VFs in a large sample of patients with bilateral glaucoma.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Glaucoma patients and suspects attending 4 regionally different secondary-care eye clinics in the United Kingdom.
  
  
  METHODS
  Binocular integrated visual fields (IVFs) using a best location method were constructed for 16 642 patients with bilateral VF loss. A significant VF defect was defined as 3 or more VF locations less than a certain sensitivity threshold, such as 20 dB. Patients were classified as having a VF defect in the inferior hemifield, superior hemifield, both hemifields, or neither hemifield. The criteria for number of locations and sensitivity threshold (in decibels) were varied across a large range of values. In addition, factor analysis was applied to the sensitivity values (in decibels) of the IVFs to determine common defect patterns in an automated fashion.
  
  
  METHODS
  Ratio of patients with binocular VF defects in the superior compared with the inferior areas of the IVF.
  
  
  RESULTS
  Estimates of the ratio of patients having binocular VF defects in the superior compared with the inferior region of the IVF ranged from 2.1 (95% confidence interval, 2.1-2.4) to as high as 5.1 (95% confidence interval, 4.7-5.5), depending on the defect criteria used. Fewer than 10% of those patients exhibiting relatively early binocular VF loss had a defect confined to the inferior region only. Common patterns of binocular VF loss were dominated chiefly by superior hemifield defects.
  
  
  CONCLUSIONS
  In a clinical population of patients with measurable VF loss in both eyes, superior-only binocular VF loss is more common than inferior-only loss. These estimates, derived from large collections of electronic medical records, are useful for interpreting findings about location of binocular VF loss impacting everyday activities and examining visual disability in glaucoma.
authors.affiliation: Division of Optometry and Visual Science, School of Health Science, City University London, London, United Kingdom.
authors.forename: Sen
authors.initials: S
authors.lastname: Hu
authors.affiliation: Division of Optometry and Visual Science, School of Health Science, City University London, London, United Kingdom.
authors.forename: Nicholas D
authors.initials: ND
authors.lastname: Smith
authors.affiliation: Division of Optometry and Visual Science, School of Health Science, City University London, London, United Kingdom.
authors.forename: Luke J
authors.initials: LJ
authors.lastname: Saunders
authors.affiliation: Division of Optometry and Visual Science, School of Health Science, City University London, London, United Kingdom. Electronic address: david.crabb.1@city.ac.uk.
authors.forename: David P
authors.initials: DP
authors.lastname: Crabb
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006423:Hemianopsia / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012189:Retrospective Studies; D012684:Sensory Thresholds; D014065:Tonometry, Ocular; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields