title: Characterisation of choroidal morphological and vascular features in diabetes and diabetic retinopathy.
abstract: We aimed to characterise specific morphological and vascular features of the choroid in Indian adults with diabetes and diabetic retinopathy (DR).
  
  
  
  Consecutive participants from the Singapore Indian Eye Study's 6-year follow-up examination underwent choroidal imaging using spectral domain optical coherence tomography (OCT) with enhanced depth imaging. Raw OCT images were loaded on a custom-written application on MATLAB that enabled delineation for detailed morphological and vascular analyses. Multiple linear regression analyses were performed to assess differences in choroidal characteristics by diabetes DR.
  
  
  
  Of the 462 recruited participants, 273 had no diabetes (mean age was 60.1±6.8 years), 100 had diabetes but no DR (61.8±7.4 years) and 89 had DR (62.4±6.0 years). In multiple regression analysis, after accounting for relevant confounders, compared with those without diabetes, participants with diabetes had significantly thinner mean choroidal thickness (CT; mean difference (MD)=-25.19 µm, p=0.001), smaller choroidal volume (MD=-0.23 mm3, p=0.003), more inflection points (MD=1.78, p<0.001) and lesser choroidal vascular area within the foveal (MD=-0.024 mm2, p=0.001) and macular (MD=-0.095 mm2, p<0.001) regions. Among the diabetic group, subjects with DR had significantly thicker mean CT (MD=25.91 µm, p=0.001), greater choroidal volume (MD=0.24 mm3, p=0.009), lesser inflection points (MD=-0.478, p=0.045) and greater choroidal vascular area at foveal (MD=0.016 mm2, p=0.019) and macular (MD=0.057 mm2, p=0.016) regions, compared with those without DR.
  
  
  
  Choroidal morphology and vasculature were altered in Indian adults with diabetes and DR. These findings may provide insights into choroidal changes in diabetes and DR.
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.
authors.forename: Preeti
authors.initials: P
authors.lastname: Gupta
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.
authors.forename: Sri Gowtham
authors.initials: SG
authors.lastname: Thakku
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Charumathi
authors.identifier: 0000-0002-4042-4719
authors.initials: C
authors.lastname: Sabanayagam
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Gavin
authors.initials: G
authors.lastname: Tan
authors.forename: Rupesh
authors.initials: R
authors.lastname: Agrawal
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Chui Ming Gemmy
authors.initials: CMG
authors.lastname: Cheung
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Ecosse L
authors.initials: EL
authors.lastname: Lamoureux
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Tien-Yin
authors.initials: TY
authors.lastname: Wong
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.|Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Ching-Yu
authors.initials: CY
authors.lastname: Cheng
mesh_terms: D002829:Choroid / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology*; D003430:Cross-Sectional Studies; D003930:Diabetic Retinopathy / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D005584:Fovea Centralis / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D041623:Tomography, Optical Coherence; D014603:Uveal Diseases / Q000000981:diagnostic imaging / Q000473:pathology*
keywords: Choroid; Diagnostic tests/Investigation; Epidemiology; Imaging