Diabetic macular edema: fundus autofluorescence and functional correlations

Area of Science:

• Ophthalmology
• Medical Imaging
• Diabetology

Background:

• Diabetic macular edema (DME) presents diverse clinical features and unpredictable treatment responses, suggesting underlying phenotypic variations.
• Understanding these phenotypes is crucial for effective DME management.

Purpose of the Study:

• To investigate the utility of structural and functional macular imaging techniques in characterizing different patterns of DME.
• To correlate findings from optical coherence tomography (OCT) and fundus autofluorescence (FAF) with microperimetry and visual acuity.

Main Methods:

• 151 eyes of 92 diabetic patients with untreated clinically significant macular edema (CSME) underwent comprehensive imaging and visual function tests.
• Evaluated parameters included best-corrected visual acuity (BCVA), OCT (central retinal thickness, volume, pattern), FAF (normal, increased, spot patterns), and microperimetry.
• Statistical analyses included linear correlation and analysis of covariance.

Main Results:

• 23.2% of eyes showed normal FAF, while 76.8% exhibited increased FAF (iFAF), with single or multiple spots.
• Retinal sensitivity was significantly reduced in areas with iFAF and in the central field for eyes with iFAF compared to normal FAF.
• OCT parameters (CRT, volume) did not differ significantly between FAF groups, but OCT patterns correlated with iFAF presence.

Conclusions:

• Fundus autofluorescence (FAF) demonstrates a stronger correlation with OCT patterns and microperimetry findings than with visual acuity in CSME.
• FAF is a rapid, noninvasive tool that provides valuable insights into DME phenotypes.
• Further research is needed to establish FAF's role in monitoring DME progression and treatment outcomes.