title: Detection of localized retinal nerve fiber layer defects with posterior pole asymmetry analysis of spectral domain optical coherence tomography.
abstract: OBJECTIVE
  To investigate the diagnostic ability of posterior pole asymmetry analysis (PPAA) with spectral domain optical coherence tomography (SD-OCT) for detecting localized retinal nerve fiber layer defects (RNFLD).
  
  
  METHODS
  Eighty-four open-angle glaucoma subjects (84 eyes) with localized, wedge-shape RNFLDs by red-free RNFL photography and 122 eyes of healthy subjects were enrolled. The subjects were examined by SD-OCT to obtain circumpapillary RNFL (cpRNFL) thickness as well as PPAA. The PPAA provides a corresponding cell to cell comparison between hemispheres within the central 20° and presents the difference using gray scale. Area under the receiver operating characteristic curve (AUROC) was calculated. The sensitivity and specificity of PPAA to detect glaucoma with the localized defects were also examined using various criteria; two consecutive black cells (criterion A), three consecutive black cells (criterion B), and four consecutive black cells (criterion C).
  
  
  RESULTS
  An AUROC of PPAA based on the number of black cells was 0.958 ± 0.013. The sensitivity and specificity of PPAA were 95.2% and 81.1% for criterion A, 83.3% and 92.6% for criterion B, and 69.0% and 98.4% for criterion C, respectively. The sensitivity and specificity of the cpRNFL thickness were 85.7% and 95.1%, respectively.
  
  
  CONCLUSIONS
  SD-OCT PPAA detects localized RNFLDs with high sensitivity and specificity, which are comparable to the cpRNFL thickness profile of OCT. These findings suggest that the PPAA can be complementary to other tests for diagnosing glaucoma in patients with localized RNFLDs.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Je Hyun
authors.initials: JH
authors.lastname: Seo
authors.forename: Tae-Woo
authors.initials: TW
authors.lastname: Kim
authors.forename: Robert N
authors.initials: RN
authors.lastname: Weinreb
authors.forename: Ki Ho
authors.initials: KH
authors.lastname: Park
authors.forename: Seok Hwan
authors.initials: SH
authors.lastname: Kim
authors.forename: Dong Myung
authors.initials: DM
authors.lastname: Kim
mesh_terms: D019540:Area Under Curve; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012372:ROC Curve; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D058609:Visual Field Tests; D014794:Visual Fields