Fundus autofluorescence and spectral domain optical coherence tomography in uveitic macular edema

Cystoid macular edema (CME) is a common vision-limiting complication of uveitis. This study correlated fundus autofluorescence (FAF) and optical coherence tomography (OCT) with visual acuity (VA).

Prospective, observational, cross-sectional study with 31 patients (53 eyes) with endogenous uveitis and fluorescein angiographically (FA) confirmed CME. Foveal thickness, epiretinal membrane formation, and altered (increased or decreased) foveal FAF were analyzed with a combined spectral domain OCT/FA device (Spectralis/HRA Heidelberg Retina Angiograph 2). Primary outcome measures were an association between central FAF with foveal thickness and VA (t-test, each). Secondary outcome measures included the association of FAF and epiretinal membrane formation, the presence of cystoid spaces in the outer plexiform and inner nuclear layers, and integrity of the third highly reflective band as detected by OCT (Fisher s exact test, each).

Of the 24 eyes (59%) with altered FAF in the central 500 microm, all had increased foveal FAF, and 10% also had increased perifoveal petaloid FAF. In eyes with altered FAF, the VA was frequently worse (p = 0.019) and foveal thickness increased (p = 0.015). Foveal thickness (mean 369.4 mum) correlated with VA (p < 0.01). FAF alterations correlated with the presence of cystoid spaces in the outer plexiform and inner nuclear layer in OCT (p < 0.001). Epiretinal membrane formation (70%) was associated with increased foveal thickness (p = 0.003) and poor VA (p = 0.08). Irregularity or loss of the third HRB (51%) correlated with poor VA (p < 0.01) and altered central FAF (p = 0.031).

FAF and OCT are useful diagnostic tools for the evaluation of uveitic CME. Increased central FAF, presence of cystoid retinal changes and disrupted third highly reflective band in OCT, and epiretinal membrane formation are associated with poor vision.