title: Comparison of macular and peripapillary measurements for the detection of glaucoma: an optical coherence tomography study.
abstract: OBJECTIVE
  To evaluate macular nerve fiber layer (NFL) thickness in glaucomatous damage by optical coherence tomography (OCT) and to compare its discriminating power for glaucoma and glaucoma suspects with that of total macular thickness and peripapillary NFL thickness.
  
  
  METHODS
  Cross-sectional, case-control, comparative study.
  
  
  METHODS
  A total of 133 eyes from 133 subjects including 46 normal eyes, 48 glaucoma-suspect eyes, and 39 glaucoma eyes were enrolled.
  
  
  METHODS
  Macular NFL thickness, total macular thickness, and peripapillary NFL thickness were measured by Stratus OCT in each diagnostic group.
  
  
  METHODS
  The patterns and measurements of macular NFL, total macular, and peripapillary NFL thickness in total mean, 4 quadrants, and 12 clock hours. The discriminating power of each parameter for detection of glaucoma suspects and glaucoma was evaluated by areas under the receiver operating characteristic curve (AROC). Correspondence with visual field function was studied by linear regression analysis.
  
  
  RESULTS
  The macular NFL profile exhibited a double-hump pattern with peaks over superonasal and inferonasal sectors. A significant difference in macular NFL thickness between normal and glaucoma-suspect groups was found at the 6-o'clock position, whereas a difference was found in all except the temporal clock hours between normal and glaucoma subjects. No significant difference in AROCs for detection of glaucoma suspects or glaucoma was found when macular NFL thickness and total macular thickness measurements were compared. However, mean macular NFL thickness demonstrated a stronger correlation with visual function than mean macular thickness (r = 0.39/R2 = 0.15 vs. r = 0.23/R2 = 0.05, P =0.042). Among all the findings, inferior peripapillary NFL thickness had the best performance in discriminating glaucoma (AROC, 0.91) and glaucoma suspects (AROC, 0.67). It also had the strongest correlation with visual function (r = 0.60/R2 = 0.36, P<0.001).
  
  
  CONCLUSIONS
  Macular NFL thickness was significantly reduced in glaucoma. It had a similar discriminating power for glaucoma detection but a stronger correlation with visual function than total macular thickness. Peripapillary NFL thickness, however, outperformed both total macular and macular NFL thickness in terms of glaucoma detection and visual function correlation. Peripapillary NFL thickness, as a total measurement of both macular and peripheral NFL, is still the best surrogate marker in glaucoma assessment.
authors.affiliation: Department of Ophthalmology, Caritas Medical Centre, Hong Kong, China. tlims00@hotmail.com
authors.forename: Christopher K S
authors.initials: CK
authors.lastname: Leung
authors.forename: Wai-Man
authors.initials: WM
authors.lastname: Chan
authors.forename: Wing-Ho
authors.initials: WH
authors.lastname: Yung
authors.forename: Alan C K
authors.initials: AC
authors.lastname: Ng
authors.forename: Jackson
authors.initials: J
authors.lastname: Woo
authors.forename: Moon-Kong
authors.initials: MK
authors.lastname: Tsang
authors.forename: Raymond K K
authors.initials: RK
authors.lastname: Tse
mesh_terms: D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D008266:Macula Lutea / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009798:Ocular Hypertension / Q000175:diagnosis; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012372:ROC Curve; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014794:Visual Fields