title: The prevalence of diabetic retinopathy in Trang province determined by retinal photography and comprehensive eye examination.
abstract: OBJECTIVE
  To determine the prevalence of diabetic retinopathy (DR) in Trang province using retinal photography and comprehensive eye examination.
  
  
  METHODS
  Seven hundred fourteen patients with diabetes (7% of the total number of diabetes in the province) were examined by single-field digital retinal photography interpreted by a retinal specialist and a stereoscopic method using indirect ophthalmolscopy and slit lamp biomicroscopy with wide field contact lens. The latter method was performed by an experienced ophthalmologist assisted by the same retinal specialist.
  
  
  RESULTS
  There was 19.2% nonproliferative diabetic retinopathy (NPDR), and 1.1% proliferative diabetic retinopathy (PDR), identified by the comprehensive examination for the right eyes. This modality also identified 18.5% NPDR, and 1.3% PDR, for the left eyes. There was 23.8% nonproliferative diabetic retinopathy (NPDR), and 1.4% proliferative diabetic retinopathy (PDR) identified by retinal photography for the right eyes. This modality also identified 22.6% NPDR, and 1.3% PDR for the left eyes. The sight-threatening cases were identified by both modalities with approximately 3% for both eyes. The photography had moderate agreement (K = 0.5, both eyes) with the comprehensive examination for the identification of diabetic macular edema with 78.6% and 68.8% sensitivity for the right and left eyes. For the identification of moderate NPDR, severe NPDR, and PDR, the photography had substantial agreement (K = 0.7, both eyes) with 88.2% and 83.3 sensitivity for the right and left eyes.
  
  
  CONCLUSIONS
  Trang province may have approximately 300 sight-threatening DR patients. This may project to 180,000 patients nationwide. Retinal photography may determine more cases than clinical examination. Combination of both modalities for DR identification may yield a closer estimate to the real prevalence.
authors.affiliation: Department of Ophthalmology, Trang Provincial Hospital, Trang, Thailand. trgtrang@hotmail.com
authors.forename: Supachai
authors.initials: S
authors.lastname: Supapluksakul
authors.forename: Paisan
authors.initials: P
authors.lastname: Ruamviboonsuk
authors.forename: Wansa
authors.initials: W
authors.lastname: Chaowakul
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003930:Diabetic Retinopathy / Q000175:diagnosis / Q000453:epidemiology*; D016021:Epidemiologic Studies; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012160:Retina / Q000473:pathology*; D042262:Retinoscopy; D013785:Thailand / Q000453:epidemiology; D015351:Vision Screening