title: Improving glaucoma detection using spatially correspondent clusters of damage and by combining standard automated perimetry and optical coherence tomography.
abstract: OBJECTIVE
  To improve the detection of glaucoma, techniques for assessing local patterns of damage and for combining structure and function were developed.
  
  
  METHODS
  Standard automated perimetry (SAP) and frequency-domain optical coherence tomography (fdOCT) data, consisting of macular retinal ganglion cell plus inner plexiform layer (mRGCPL) as well as macular and optic disc retinal nerve fiber layer (mRNFL and dRNFL) thicknesses, were collected from 52 eyes of 52 healthy controls and 156 eyes of 96 glaucoma suspects and patients. In addition to generating simple global metrics, SAP and fdOCT data were searched for contiguous clusters of abnormal points and converted to a continuous metric (pcc). The pcc metric, along with simpler methods, was used to combine the information from the SAP and fdOCT. The performance of different methods was assessed using the area under receiver operator characteristic curves (AROC scores).
  
  
  RESULTS
  The pcc metric performed better than simple global measures for both the fdOCT and SAP. The best combined structure-function metric (mRGCPL&SAP pcc, AROC = 0.868 ± 0.032) was better (statistically significant) than the best metrics for independent measures of structure and function. When SAP was used as part of the inclusion and exclusion criteria, AROC scores increased for all metrics, including the best combined structure-function metric (AROC = 0.975 ± 0.014).
  
  
  CONCLUSIONS
  A combined structure-function metric improved the detection of glaucomatous eyes. Overall, the primary sources of value-added for glaucoma detection stem from the continuous cluster search (the pcc), the mRGCPL data, and the combination of structure and function.
authors.affiliation: Department of Psychology, Columbia University, New York, New York.
authors.forename: Ali S
authors.initials: AS
authors.lastname: Raza
authors.forename: Xian
authors.initials: X
authors.lastname: Zhang
authors.forename: Carlos G V
authors.initials: CG
authors.lastname: De Moraes
authors.forename: Charles A
authors.initials: CA
authors.lastname: Reisman
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Liebmann
authors.forename: Robert
authors.initials: R
authors.lastname: Ritch
authors.forename: Donald C
authors.initials: DC
authors.lastname: Hood
mesh_terms: D000465:Algorithms; D005260:Female; D005901:Glaucoma / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology; D012372:ROC Curve; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology; D041623:Tomography, Optical Coherence / Q000379:methods / Q000639:trends; D058609:Visual Field Tests / Q000379:methods / Q000639:trends*; D014794:Visual Fields
keywords: detection; diagnosis; glaucoma; glaucomatous; macula; optical coherence tomography; retinal ganglion cells; retinal nerve fiber layer; sensitivity; specificity; standard automated perimetry; visual fields