title: Comparison between binocular indirect ophthalmoscopy and digital retinography for diabetic retinopathy screening: the multicenter Brazilian Type 1 Diabetes Study.
abstract: BACKGROUND
  Diabetic retinopathy is the main cause of preventable blindness in the economically active population in western countries. Diabetic retinopathy screening is effective in preventing blindness and can be performed through various diagnostic methods. Our objective is to compare binocular indirect ophthalmoscopy (BIO) to telemedicine protocols of digital retinography for diabetic retinopathy screening in a large and heterogenous type 1 diabetes population in a developing country.
  
  
  METHODS
  Data from 1266 Type 1 Diabetes Mellitus patients from a Brazilian multicenter study were analyzed. Patients underwent BIO and digital retinography, non-mydriatic and mydriatic. Images were sent to a reading center in a telemedicine protocol. Agreement between the different methods was calculated with kappa statistic for diabetic retinopathy and maculopathy classification. Clinical outcome was either observation or referral to specialist.
  
  
  RESULTS
  Agreement between BIO and mydriatic retinography was substantial (kappa 0.67-0.74) for diabetic retinopathy observation vs referral classification. Agreement was fair to moderate (kappa 0.24-0.45) between retinography and BIO for maculopathy. Poor mydriasis was the main obstacle to image reading and classification, especially on the non-mydriatic strategy, occurring in 11.9 % of right eyes and 16.9 % of left eyes.
  
  
  CONCLUSIONS
  Mydriatic retinography showed a substantial agreement to BIO for diabetic retinopathy observation vs referral classification. A significant amount of information was lost on the non-mydriatic technique because of poor mydriasis. We recommend a telemedicine-based diabetic retinopathy screening strategy with digital mydriatic retinography, preferably with 2 fields, and advise against non-mydriatic retinography in developing countries.
authors.affiliation: Departments of Endocrinology and Ophthalmology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Fernando Korn
authors.initials: FK
authors.lastname: Malerbi
authors.affiliation: Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: Morales
authors.affiliation: Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Michel Eid
authors.initials: ME
authors.lastname: Farah
authors.affiliation: Department of Ophthalmology, Hospital Federal dos Servidores do Estado, Rio de Janeiro, Brazil.
authors.forename: Karla Rezende Guerra
authors.initials: KR
authors.lastname: Drummond
authors.affiliation: Department of Ophthalmology, Centro de Endocrinologia e Diabetes do Estado da Bahia, Salvador, Brazil.
authors.forename: Tessa Cerqueira Lemos
authors.initials: TC
authors.lastname: Mattos
authors.affiliation: Department of Ophthalmology, Hospital Regional de Taguatinga, Brasília, Brazil.
authors.forename: André Araújo
authors.initials: AA
authors.lastname: Pinheiro
authors.affiliation: Department of Ophthalmology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Felipe
authors.initials: F
authors.lastname: Mallmann
authors.affiliation: Department of Endocrinology, University of São Paulo, São Paulo, Brazil.
authors.forename: Ricardo Vessoni
authors.initials: RV
authors.lastname: Perez
authors.affiliation: Department of Ophthalmology, University of Campinas, Campinas, Brazil.
authors.forename: Franz Schubert Lopes
authors.initials: FS
authors.lastname: Leal
authors.affiliation: Department of Endocrinology, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Marília Brito
authors.initials: MB
authors.lastname: Gomes
authors.affiliation: Department of Endocrinology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Sergio Atala
authors.initials: SA
authors.lastname: Dib
keywords: Blindness; Diabetic retinopathy; Retinography; Screening; Telemedicine