Correlation between optical coherence tomography and fluorescein angiography findings in diabetic macular edema.

OBJECTIVE: To report the relationship between the findings of third-generation optical coherence tomography (OCT) and fluorescein angiography (FA) in eyes with diabetic macular edema (DME).
DESIGN: Small case series. PARTICIPANTS: Four eyes with DME.
METHODS: We compared findings from late-phase FA with corresponding cross-sectional OCT images using 5-mm-long horizontal and vertical scans. MAIN OUTCOME MEASURES: Fluorescein angiography and OCT findings in DME.
RESULTS: Fluorescein angiography showed dye pooling within the cystic spaces with a petalloid pattern in the foveal area in all eyes; 3 eyes had cystic spaces primarily in the outer plexiform layer (OPL) on OCT. In 16 perifoveal areas in 4 eyes, FA showed hyperfluorescence with a honeycomb pattern in 7 areas, petalloid pattern in 3, and diffuse pattern in 3. The remaining 3 perifoveal areas had no hyperfluorescence. Optical coherence tomography showed that the perifoveal areas with a honeycomb pattern of hyperfluorescence had not only swelling of the OPL but also cystoid spaces located in the inner nuclear layer (INL). The perifoveal areas with no honeycomb pattern but petalloid or diffuse hyperfluorescence had only retinal swelling of the OPL. In the remaining 3 perifoveal areas without hyperfluorescence, OCT showed almost normal retinal structures.
CONCLUSIONS: Diabetic macular edema typically showed 2 patterns of dye pooling on late-phase FA (i.e., petalloid in the fovea and honeycomb in the perifoveal area). The dye pooling corresponded to large cystic spaces in the OPL, and the honeycomb pattern to small cystic spaces in the INL.