title: Choroidal thickness and high myopia: a case-control study of young Chinese men in Singapore.
abstract: OBJECTIVE
  To determine the distribution of choroidal thickness (CT) and ocular factors associated with CT in high myopic eyes in comparison with emmetropic eyes of young healthy adults.
  
  
  METHODS
  A case-control study of 648 young, male subjects, including 520 high myopes and 128 emmetropes. Choroidal imaging was performed using enhanced depth imaging spectral domain optical coherence tomography. Images were postprocessed using adaptive compensation for quality enhancement. CT was measured at nine locations, including subfovea and 1.5 and 3 mm nasal, temporal, superior and inferior to fovea.
  
  
  RESULTS
  The CT at the subfovea was significantly thinner (mean ± standard error: 225.87 ± 5.51 μm) for high myopes compared to emmetropes (375.15 ± 6.58 μm, p < 0.001). Likewise, CT in high myopic group was significantly thinner than emmetropic control group at all locations (p for trend <0.001 for all locations). Distribution of CT showed a markedly different pattern in high myopic eyes (thickest superiorly at 3 mm, 265.97 ± 5.97 μm) and emmetropic eyes (thickest subfoveally, 375.15 ± 6.58 μm). Choroid was thinnest at nasal 3 mm location in both the myopic (108.85 ± 3.97 μm) and emmetropic (238.25 ± 6.72 μm) groups. Among the ocular factors studied, axial length, posterior staphyloma and chorio-retinal atrophy were the significant predictors of CT.
  
  
  CONCLUSIONS
  Highly myopic eyes have significantly thinner choroid and showed different distribution pattern, compared to emmetropes. Axial length, posterior staphyloma and chorio-retinal atrophy are the strongest determinants of CT.
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.
authors.forename: Preeti
authors.initials: P
authors.lastname: Gupta
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.|Saw Swee Hock School of Public Health, National University of Singapore, Singapore.
authors.forename: Seang-Mei
authors.initials: SM
authors.lastname: Saw
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.|Office of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore.
authors.forename: Carol Y
authors.initials: CY
authors.lastname: Cheung
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Bioengineering, Faculty of Engineering, National University of Singapore, Singapore.
authors.forename: Michael J A
authors.initials: MJ
authors.lastname: Girard
authors.affiliation: Department of Medical Physics and Bioengineering, Faculty of Engineering Science, University College London, London, UK.
authors.forename: Jean Martial
authors.initials: JM
authors.lastname: Mari
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.
authors.forename: Mayuri
authors.initials: M
authors.lastname: Bhargava
authors.affiliation: Department of Ophthalmology, Tan Tock Seng Hospital, Singapore.
authors.forename: Colin
authors.initials: C
authors.lastname: Tan
authors.affiliation: DSO National Laboratories, Defense Medical and Environmental Research Institute, Singapore.
authors.forename: Mellisa
authors.initials: M
authors.lastname: Tan
authors.affiliation: DSO National Laboratories, Defense Medical and Environmental Research Institute, Singapore.
authors.forename: Adeline
authors.initials: A
authors.lastname: Yang
authors.affiliation: DSO National Laboratories, Defense Medical and Environmental Research Institute, Singapore.
authors.forename: Frederick
authors.initials: F
authors.lastname: Tey
authors.affiliation: Vision Performance Centre, Military Medical Institute, Singapore Armed Forces, Singapore.
authors.forename: Gerard
authors.initials: G
authors.lastname: Nah
authors.affiliation: Vision Performance Centre, Military Medical Institute, Singapore Armed Forces, Singapore.
authors.forename: Paul
authors.initials: P
authors.lastname: Zhao
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.|Saw Swee Hock School of Public Health, National University of Singapore, Singapore.|Office of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore.
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore.|Saw Swee Hock School of Public Health, National University of Singapore, Singapore.|Office of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore.
authors.forename: Ching-Yu
authors.initials: CY
authors.lastname: Cheng
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000208:ethnology*; D001284:Atrophy; D058452:Axial Length, Eye / Q000473:pathology; D001699:Biometry; D016022:Case-Control Studies; D002829:Choroid / Q000473:pathology*; D058453:Emmetropia / Q000502:physiology; D006801:Humans; D008297:Male; D047728:Myopia, Degenerative / Q000208:ethnology / Q000503:physiopathology*; D009929:Organ Size; D012160:Retina / Q000473:pathology; D012846:Singapore / Q000453:epidemiology; D041623:Tomography, Optical Coherence; D055815:Young Adult
keywords: EDI SD-OCT; case-control study; choroidal thickness; high myopia