title: Diabetic retinopathy screening using digital non-mydriatic fundus photography and automated image analysis.
abstract: OBJECTIVE
  To investigate the use of automated image analysis for the detection of diabetic retinopathy (DR) in fundus photographs captured with and without pharmacological pupil dilation using a digital non-mydriatic camera.
  
  
  METHODS
  A total of 83 patients (165 eyes) with type 1 or type 2 diabetes, representing the full spectrum of DR, were photographed with and without pharmacological pupil dilation using a digital non-mydriatic camera. Two sets of five overlapping, non-stereoscopic, 45-degree field images of each eye were obtained. All images were graded in a masked fashion by two readers according to ETDRS standards and disagreements were settled by an independent adjudicator. Automated detection of red lesions as well as image quality control was made: detection of a single red lesion or insufficient image quality was categorized as possible DR.
  
  
  RESULTS
  At patient level, the automated red lesion detection and image quality control combined demonstrated a sensitivity of 89.9% and specificity of 85.7% in detecting DR when used on images captured without pupil dilation, and a sensitivity of 97.0% and specificity of 75.0% when used on images captured with pupil dilation. For moderate non-proliferative or more severe DR the sensitivity was 100% for images captured both with and without pupil dilation.
  
  
  CONCLUSIONS
  Our results demonstrate that the described automated image analysis system, which detects the presence or absence of DR, can be used as a first-step screening tool in DR screening with considerable effectiveness.
authors.affiliation: Department of Ophthalmology, Herlev Hospital, University of Copenhagen, Denmark. anbha@herlevhosp.kbhamt.dk
authors.forename: Anja B
authors.initials: AB
authors.lastname: Hansen
authors.forename: Niels V
authors.initials: NV
authors.lastname: Hartvig
authors.forename: Maja S
authors.initials: MS
authors.lastname: Jensen
authors.forename: Knut
authors.initials: K
authors.lastname: Borch-Johnsen
authors.forename: Henrik
authors.initials: H
authors.lastname: Lund-Andersen
authors.forename: Michael
authors.initials: M
authors.lastname: Larsen
mesh_terms: D019540:Area Under Curve; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D003941:Diagnostic Techniques, Ophthalmological; D005189:False Positive Reactions; D005654:Fundus Oculi; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D009184:Mydriatics / Q000008:administration & dosage; D010781:Photography / Q000379:methods*; D011680:Pupil / Q000187:drug effects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D009184:Mydriatics