Computer-assisted microaneurysm turnover in the early stages of diabetic retinopathy.
Bernardes R., Nunes S., Pereira I., Torrent T., Rosa A., Coelho D., Cunha-Vaz J.
Purpose: To assess the reliability of microaneurysm turnover, computed from color fundus photographs, in evaluating diabetic retinopathy in patients with type 2 diabetes and nonproliferative retinopathy.
Methods: A new method (MA-Tracker) was developed to count microaneurysms by mapping their locations through image co-registration. To compute the reliability of microaneurysm turnover, 3 different graders were asked to earmark microaneurysms on the same set of color fundus photographs.
Results: The total numbers of microaneurysms earmarked in each of 5 visits suggest that microaneurysms remain stable over time (p 0.138). However, an analysis of each microaneurysm showed that only 29.4% remained at the same location. By computing the formation and disappearance rates of microaneurysms (2.3 and 1.7 microaneurysms/year, respectively), a significant turnover of microaneurysms was found.
Conclusions: The formation and disappearance rates of microaneurysms obtained from color fundus photographs using MA-Tracker show very good agreement between different graders, and can be used as indicators of microaneurysm turnover in the initial stages of diabetic retinopathy.
Ophtalmologica, 2009; 223(5):284-291.
2009
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