title: Differences between Non-arteritic Anterior Ischemic Optic Neuropathy and Open Angle Glaucoma with Altitudinal Visual Field Defect.
abstract: OBJECTIVE
  To investigate the differences in retinal nerve fiber layer (RNFL) change and optic nerve head parameters between non-arteritic anterior ischemic optic neuropathy (NAION) and open angle glaucoma (OAG) with altitudinal visual field defect.
  
  
  METHODS
  Seventeen NAION patients and 26 OAG patients were enrolled prospectively. The standard visual field indices (mean deviation, pattern standard deviation) were obtained from the Humphrey visual field test and differences between the two groups were analyzed. Cirrus HD-OCT parameters were used, including optic disc head analysis, average RNFL thickness, and RNFL thickness of each quadrant.
  
  
  RESULTS
  The mean deviation and pattern standard deviation were not significantly different between the groups. In the affected eye, although the disc area was similar between the two groups (2.00 ± 0.32 and 1.99 ± 0.33 mm(2), p = 0.586), the rim area of the OAG group was smaller than that of the NAION group (1.26 ± 0.56 and 0.61 ± 0.15 mm(2), respectively, p < 0.001). RNFL asymmetry was not different between the two groups (p = 0.265), but the inferior RNFL thickness of both the affected and unaffected eyes were less in the OAG group than in the NAION group. In the analysis of optic disc morphology, both affected and unaffected eyes showed significant differences between two groups.
  
  
  CONCLUSIONS
  To differentiate NAION from OAG in eyes with altitudinal visual field defects, optic disc head analysis of not only the affected eye, but also the unaffected eye, by using spectral domain optical coherence tomography may be helpful.
authors.affiliation: Department of Ophthalmology, Kim's Eye Hospital, Seoul, Korea.
authors.forename: Sangyoun
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Ophthalmology, Kim's Eye Hospital, Seoul, Korea.
authors.forename: Jong Jin
authors.initials: JJ
authors.lastname: Jung
authors.affiliation: Department of Ophthalmology, Kim's Eye Hospital, Seoul, Korea. ; Department of Ophthalmology, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Ungsoo Samuel
authors.initials: US
authors.lastname: Kim
mesh_terms: D000368:Aged; D001167:Arteritis / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D018917:Optic Neuropathy, Ischemic / Q000175:diagnosis*; D011446:Prospective Studies; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000175:diagnosis*; D058609:Visual Field Tests; D014794:Visual Fields
keywords: Glaucoma; Ischemic optic neuropathy; Visual field tests