Abstract
Purpose: :
To evaluate fundus autofluorescence (FAF) changes after treatment of cystoid diabetic macular edema (DME).
Methods: :
In this retrospective study, we evaluated 156 eyes of 89 patients who underwent treatment for cystoid DME. Seventy eight of 156 eyes fulfilled the inclusion criteria of having: previously untreated cystoid DME and 5 types of imaging modalities carried out on the same day. Imaging modalities were: colour fundus photo of the ETDRS field 2, FAF, fluorescein angiography (FA), OCT and microperimetry before and after treatment. Modified ETDRS photocoagulation, subthreshold micropulse diode laser (MPDL), or intravitreal triamcinolone (IVT) were used in this population.
Results: :
Of 78 included eyes: 45 underwent laser treatment (26 modified ETDRS, 19 MPDL) and 33 underwent IVT. Before treatment, 53 eyes (68%) had increased foveal FAF, whereas 25 (32%) had normal FAF. FAF changed over laser spots in the modified ETDRS group, but not in the MPDL group. Foveal FAF never changed in both laser treated groups, regardless retinal thickness changes. In the IVT group, pathologic foveal FAF always returned to normal. Mean retinal sensitivity decreased after modified ETDRS laser and increased after MPDL and IVT, (p<0.005).
Conclusions: :
The pathophysiology of increased fundus autofluorescence in cystoid diabetic macular edema is still controversial. Different mechanisms and retinal cells have been hypothesized to contribute to the changes of FAF in cystoid DME. Abnormal FAF seems not to be influenced by successful local laser treatment, of any kind. Whereas, corticosteroids are able to modify FAF abnormalities. FAF data in eyes with cystoid DME may contribute to the understanding of different results after treatment.
Keywords: diabetic retinopathy • edema • imaging/image analysis: clinical