Choroidal Variations in Diabetic Macular Edema: Fluorescein Angiography and Optical Coherence Tomography

To (i) evaluate variations in choroidal thickness (CT) and choroidal volume (CV) in diabetic macular edema (DME), as demonstrated by fluorescein angiography (FA) and enhanced depth-imaging (EDI) optical coherence tomography (OCT) (EDI-OCT) and (ii) correlate these variations with visual acuity.

This study was a retrospective observational case series of patients with diabetic retinopathy (DR) and DME. The study groups comprised 77 DR patients (n = 87), all of whom underwent color fundus photography, FA, and OCT on the same day. The control group comprised 25 age-matched healthy individuals (n = 50 eyes). CT was measured by manual segmentation (EDI-OCT built-in automated retinal segmentation software). Variations in CT in DME patterns were analyzed.

We studied a total of 87 eyes from patients with DR, including 50 eyes from 25 patients with DME (DME group) and 37 eyes from 22 patients without DME (non-DME group). For DME-group patients, mean subfoveal choroidal thickness (SFCT) and total CV (TCV) were 258.8 ± 81.7 µm and 6.6 ± 1.8 mm³, respectively. For non-DME group patients, mean SFCT and TCV values were 247.6 ± 73.3 µm and 6.6 ± 1.6 mm³, respectively. SFCT and TCV values for both groups were significantly lower than for healthy controls (294.3 ± 87.6 µm and 7.7 ± 1.8 mm,³ respectively) (p = 0.040 and 0.019, respectively). CTs varied according to morphological FA and OCT patterns of DME, but did not differ significantly (p > 0.05).

CT and CV in DR patients were decreased compared with healthy controls. CTs did not differ significantly between DME patterns demonstrated by OCT and FA.