title: Discriminating between glaucoma and normal eyes using optical coherence tomography and the 'Random Forests' classifier.
abstract: OBJECTIVE
  To diagnose glaucoma based on spectral domain optical coherence tomography (SD-OCT) measurements using the 'Random Forests' method.
  
  
  METHODS
  SD-OCT was conducted in 126 eyes of 126 open angle glaucoma (OAG) patients and 84 eyes of 84 normal subjects. The Random Forests method was then applied to discriminate between glaucoma and normal eyes using 151 OCT parameters including thickness measurements of circumpapillary retinal nerve fiber layer (cpRNFL), the macular RNFL (mRNFL) and the ganglion cell layer-inner plexiform layer combined (GCIPL). The area under the receiver operating characteristic curve (AROC) was calculated using the Random Forests method adopting leave-one-out cross validation. For comparison, AROCs were calculated based on each one of the 151 OCT parameters.
  
  
  RESULTS
  The AROC obtained with the Random Forests method was 98.5% [95% Confidence interval (CI): 97.1-99.9%], which was significantly larger than the AROCs derived from any single OCT parameter (maxima were: 92.8 [CI: 89.4-96.2] %, 94.3 [CI: 91.1-97.6] % and 91.8 [CI: 88.2-95.4] % for cpRNFL-, mRNFL- and GCIPL-related parameters, respectively; P<0.05, DeLong's method with Holm's correction for multiple comparisons). The partial AROC above specificity of 80%, for the Random Forests method was equal to 18.5 [CI: 16.8-19.6] %, which was also significantly larger than the AROCs of any single OCT parameter (P<0.05, Bootstrap method with Holm's correction for multiple comparisons).
  
  
  CONCLUSIONS
  The Random Forests method, analyzing multiple SD-OCT parameters concurrently, significantly improves the diagnosis of glaucoma compared with using any single SD-OCT measurement.
authors.affiliation: Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Yoshida
authors.affiliation: Tajimi Iwase Eye Clinic, Tajimi, Japan.
authors.forename: Aiko
authors.initials: A
authors.lastname: Iwase
authors.affiliation: Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroyo
authors.initials: H
authors.lastname: Hirasawa
authors.affiliation: Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Murata
authors.affiliation: Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Mayama
authors.affiliation: Kanto Central Hospital of the Mutual Aid Association of Public School Teachers, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Araie
authors.affiliation: Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Asaoka
mesh_terms: D000328:Adult; D000368:Aged; D005123:Eye / Q000473:pathology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D012372:ROC Curve; D041623:Tomography, Optical Coherence / Q000379:methods*