The efficacy of automated "disease/no disease" grading for diabetic retinopathy in a systematic screening programme.
OBJECTIVE
To assess the efficacy of automated "disease/no disease" grading for diabetic retinopathy within a systematic screening programme.


METHODS
Anonymised images were obtained from consecutive patients attending a regional primary care based diabetic retinopathy screening programme. A training set of 1067 images was used to develop automated grading algorithms. The final software was tested using a separate set of 14 406 images from 6722 patients. The sensitivity and specificity of manual and automated systems operating as "disease/no disease" graders (detecting poor quality images and any diabetic retinopathy) were determined relative to a clinical reference standard.


RESULTS
The reference standard classified 8.2% of the patients as having ungradeable images (technical failures) and 62.5% as having no retinopathy. Detection of technical failures or any retinopathy was achieved by manual grading with 86.5% sensitivity (95% confidence interval 85.1 to 87.8) and 95.3% specificity (94.6 to 95.9) and by automated grading with 90.5% sensitivity (89.3 to 91.6) and 67.4% specificity (66.0 to 68.8). Manual and automated grading detected 99.1% and 97.9%, respectively, of patients with referable or observable retinopathy/maculopathy. Manual and automated grading detected 95.7% and 99.8%, respectively, of technical failures.


CONCLUSIONS
Automated "disease/no disease" grading of diabetic retinopathy could safely reduce the burden of grading in diabetic retinopathy screening programmes.
Philip
S
S
Biomedical Physics and Grampian Retinal Screening Programme, University of Aberdeen, Foresterhill, Aberdeen.
Fleming
A D
AD
Goatman
K A
KA
Fonseca
S
S
McNamee
P
P
Scotland
G S
GS
Prescott
G J
GJ
Sharp
P F
PF
Olson
J A
JA
D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D015397:Program Evaluation; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index