[Use of retinal photography in the diagnosis of diabetic macular edema]. / Utilidad de las retinografías en el diagnóstico del edema macular diabético.

OBJECTIVE: To determine the validity of retinal photography in the diagnosis of diabetic macular edema. Determine the number and size of the photographs for its correct diagnosis. METHODS: Cross-sectional observational study consisting of 420 eyes of patients with diabetic retinopathy, using a combination of retinography (simple, stereoscopic, red-free light), after expansion, to determine its validity in the diagnosis of diabetic macular edema. Sensitivity, specificity, positive and negative predictive values and the correlation with the gold standard test (optical coherence tomography) were calculated. The retinographs were evaluated by three experts and their results analyzed by the statistical program SPSS 15.0 Windows. RESULTS: Sensitivities were below 80% in simple photographs and above 80% in the stereoscopic retinography, whereas those associated with red-free filters, reaching the 30° green stereoscopic photography, showed a sensitivity of 94.3%. The specificity was 95% in color and red-free stereoscopic retinography of 45° and 30°. The positive predictive value was greater than 95% and the negative value greater than 90% with a coefficient of agreement of 80%, and a degree of consistency with the benchmark of over 80%. CONCLUSIONS: The results of the stereoscopic retinographs are sufficient to enable them to be used in screening for diabetic macular edema. The use of a green filter and its combination with visual acuity improves results in the diagnosis of this disease.