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

Purposes: 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 depthimaging (EDI) optical coherence tomography (OCT) (EDI-OCT) and (ii) correlate these variations with visual acuity. Methods: 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. Results: 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 mu m and 6.6 +/- 1.8 mm(3), respectively. For non-DME group patients, mean SFCT and TCV values were 247.6 +/- 73.3 mu m and 6.6 +/- 1.6 mm(3), respectively. SFCT and TCV values for both groups were significantly lower than for healthy controls (294.3 +/- 87.6 mu m 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). Conclusions: 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.