Microaneurysm turnover is a biomarker for diabetic retinopathy progression to clinically significant macular edema: findings for type 2 diabetics with nonproliferative retinopathy.
OBJECTIVE
To examine the relationship between microaneurysm turnover (formation rate), using a new semi-automatic method (MA-Tracker) based on color fundus photographs, and diabetic retinopathy (DR) progression to clinically significant macular edema (CSME).


METHODS
In total, 113 patients/eyes with nonproliferative DR (NPDR) were followed up every 6 months for 2 years as controls of the DR clinical trials, and by conventional general and ophthalmological care for the next 8 years (over a total of 10 years' follow-up). Microaneurysm turnover for the 2 first years was computed using the MA-Tracker.


RESULTS
The 17 patients that developed CSME over the 10 years of follow-up presented a microaneurysm formation rate of 9.2 +/- 18.2 microaneurysms/year (mean +/- SD) during the first 2 years, which was statistically higher than the eyes that did not develop CSME (0.5 +/- 1.2 microaneurysms/year, p < 0.001). These 17 patients also presented higher HbA(1C) levels at baseline (8.5 +/- 1.2%) compared to the patients who did not develop CSME (7.3 +/- 1.2%, p = 0.001).


CONCLUSIONS
A high microaneurysm formation rate on color fundus photographs appears to be a good biomarker for DR progression to CSME in type 2 diabetic patients with NPDR.
Nunes
Sandrina
S
Association for Innovation and Biomedical Research on Light and Image, University of Coimbra, Coimbra, Portugal.
Pires
Isabel
I
Rosa
Andreia
A
Duarte
Lilianne
L
Bernardes
Rui
R
Cunha-Vaz
José
J
D000328:Adult; D000368:Aged; D000783:Aneurysm / Q000175:diagnosis*; D015415:Biomarkers; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000503:physiopathology*; D003941:Diagnostic Techniques, Ophthalmological; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008269:Macular Edema / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010781:Photography; D012171:Retinal Vessels / Q000473:pathology*; D012189:Retrospective Studies
D015415:Biomarkers