Grading diabetic retinopathy severity from compressed digital retinal images compared with uncompressed images and film

Retina. Nov-Dec 2010;30(10):1651-61. doi: 10.1097/IAE.0b013e3181e3790b.


Purpose: To compare research grading of diabetic retinopathy (DR) severity level from compressed digital images versus uncompressed images and film.

Methods: Compressed (JPEG2000, 37:1) digital images (C) were compared with uncompressed digital (U) and film (F) stereoscopic photographs from a 152-eye cohort with full-spectrum Early Treatment Diabetic Retinopathy Study severity levels for agreement on severity level, DR presence with ascending severity threshold, presence of DR index lesions, and repeatability of grading.

Results: Classification of Early Treatment Diabetic Retinopathy Study severity levels from C images agreed substantially with results from F images (κ = 0.60, κ(w) [linear weighted] = 0.86) and uncompressed digital images (κ = 0.76, κ(w) = 0.92). For agreement of uncompressed digital versus F images, κ = 0.62 and κ(w) = 0.86. Distribution of Early Treatment Diabetic Retinopathy Study levels was not significantly different between C and F images (P = 0.09, Bhapkar's test for marginal homogeneity). For presence/absence of DR at 8 ascending severity thresholds, agreement between C and F was "almost perfect" (κ ≥ 0.8). Agreement on severity level between readers with C images was at least as good as that with uncompressed digital image or F. Repeatability of severity threshold grading between readers was similar using C or F images. For identifying individual DR lesions, agreement between C and F ranged from "moderate" to "perfect." Agreement of grading venous beading from C was slightly lower than from F.

Conclusion: Full Early Treatment Diabetic Retinopathy Study scale DR severity level grading using C images is comparable to that using U images or film.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Data Compression / methods*
  • Diabetic Retinopathy / classification*
  • Diabetic Retinopathy / diagnosis*
  • Diagnostic Techniques, Ophthalmological*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Photography / methods*
  • Reproducibility of Results
  • Severity of Illness Index
  • Telemedicine