Abstract
Purpose:
To measure the leakage area in each field of ETDRS grid in diabetic macular edema (DME) patients, and to explain the relationship between the aetiology of the edema and the severity of the leakage noticed in each field.
Methods:
87 consecutive DME subjects were included. Inclusion criteria: patients with diabetic macular edema and good quality fluorescein angiography (FA) images. Exclusion criteria: patients with previous ocular medical or surgical intervention, previous laser treatment in the macular region, vitreomacular traction, epiretinal membrane, accompaying macular non perfusion, other diseases which may cause macular edema like retinal vascular occlusions, inflammation, irvine-gass syndrome. Using octavo program (Vienna reading center, Vienna, Austria) we measured the leakage areas on late phase FA images in each field (nasal, inferior, temporal, superior) of ETDRS grid.
Results:
The means of leakage areas in nasal, inferior, superior, and temporal ETDRS fields were : 2335355 µm2, 2843996 µm2, 3026396 µm2,and 3963832 µm2 respectively. The differences between all means of leakage areas were statistically significant (p<0.05), except the difference between the means of leakage areas in superior and inferior fields (p=0.288).
Conclusions:
Iin diabetic retinopathy (DR), the gradual increase of leakage areas starting from nasal, inferior and superior, to superior field gets along with the spatial intensity of microaneurysms. In contrast, this increase in distribution of leakage disproportionates to the thickness map of nerve fiber layer (NFL), which shows increase in thickness from temporal, inferior and superior, to nasal field. This finding support the hypothesis that the neural components in NFL may play a remarkable role in preventing the evolution and progression of microaneurysms in DR.
Keywords: 499 diabetic retinopathy •
505 edema