title: Assessment of choroidal thickness in healthy and glaucomatous eyes using swept source optical coherence tomography.
abstract: OBJECTIVE
  To evaluate choroidal thickness (CT) in healthy and glaucomatous eyes using Swept Source Optical Coherence Tomography (SS-OCT).
  
  
  METHODS
  A cross-sectional observational study of 216 eyes of 140 subjects with glaucoma and 106 eyes of 67 healthy subjects enrolled in the Diagnostic Innovations in Glaucoma Study. CT was assessed from wide-field (12×9 mm) SS-OCT scans. The association between CT and potential confounding variables including age, gender, axial length, intraocular pressure, central corneal thickness and ocular perfusion pressure was examined using univariable and multivariable regression analyses.
  
  
  RESULTS
  Overall CT was thinner in glaucomatous eyes with a mean (± standard deviation) of 157.7±48.5 µm in glaucoma compared to 179.9±36.1 µm in healthy eyes (P<0.001). The choroid was thinner in both the peripapillary and macular regions in glaucoma compared to controls. Mean peripapillary CT was 154.1±44.1 µm and 134.0±56.9 µm (P<0.001) and macular CT 199.3±46.1 µm and 176.2±57.5 µm (P<0.001) for healthy and glaucomatous eyes respectively. However, older age (P<0.001) and longer axial length (P<0.001) were also associated with thinner choroid and when differences in age and axial length between glaucomatous and healthy subjects were accounted for, glaucoma was not significantly associated with CT. There was also no association between glaucoma severity and CT.
  
  
  CONCLUSIONS
  Glaucoma was not associated with CT measured using SS-OCT; however, older age and longer axial length were associated with thinner choroid so should be considered when interpreting CT measurements.
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America; Department of Ophthalmology, the First Affiliated Hospital, Harbin Medical University, Harbin, China.
authors.forename: Chunwei
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Tatham
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America.
authors.forename: Felipe A
authors.initials: FA
authors.lastname: Medeiros
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America.
authors.forename: Linda M
authors.initials: LM
authors.lastname: Zangwill
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, San Diego, California, United States of America.
authors.forename: Robert N
authors.initials: RN
authors.lastname: Weinreb
mesh_terms: D000368:Aged; D000375:Aging / Q000473:pathology / Q000502:physiology; D001794:Blood Pressure; D016022:Case-Control Studies; D002829:Choroid / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D005901:Glaucoma / Q000175:diagnosis* / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D041623:Tomography, Optical Coherence