Choroidal Thickness in Different Patterns of Diabetic Macular Edema

Area of Science:

• Ophthalmology
• Medical Imaging
• Diabetology

Background:

• Diabetic macular edema (DME) is a leading cause of vision loss in diabetic patients.
• Choroidal thickness (ChT) changes are implicated in DME pathogenesis, but vary with edema patterns.
• Enhanced-depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT) allows detailed choroidal analysis.

Purpose of the Study:

• To investigate choroidal thickness (ChT) variations across different diabetic macular edema (DME) patterns.
• To correlate ChT with specific DME subtypes using advanced OCT imaging.
• To compare ChT in DME patients with healthy controls.

Main Methods:

• Observational study using EDI-SD-OCT to analyze choroidal layer and measure ChT.
• Classified DME into focal macular edema (FME), spongy macular edema (SME), cystic macular edema (CME), and CME with subretinal fluid (CME+).
• Excluded participants with other retinal diseases affecting fundus view.

Main Results:

• Average ChT was 216.95 µm (FME), 243.00 µm (SME), 221.38 µm (CME), and 249.63 µm (CME+).
• Choroidal thickness was higher in diffuse edema compared to FME.
• ChT was significantly increased in CME+ compared to other DME subtypes and controls (213.88 µm).

Conclusions:

• Choroidal thickness is not uniform across all DME patterns.
• Increased ChT correlates with more severe DME, particularly diffuse edema and CME with subretinal fluid.
• These findings highlight the role of choroidal changes in DME progression and suggest potential imaging biomarkers.