Retinal Functional Impairment in Diabetic Retinopathy.

Area of Science:

• Ophthalmology
• Neuroscience
• Diabetology

Background:

• Diabetic retinopathy (DR) is a neurodegenerative retinal disease.
• Type 2 diabetes is a major risk factor for DR.
• Early detection of DR is crucial for management.

Purpose of the Study:

• To analyze latency changes in full-field electroretinograms (ERGs) in patients with type 2 diabetes.
• To correlate ERG findings with DR severity.
• To assess the neurodegenerative impact of DR on the retina.

Main Methods:

• Prospective study including 59 participants: 15 diabetic patients without DR, 16 with non-proliferative DR, 14 with pre-proliferative DR, 15 with proliferative DR, and 14 age-matched controls.
• Ophthalmologic examination and full-field ERGs recorded using the Metrovision MonPackOne system.
• Analysis of "a"- and "b"-wave latencies in dark-adapted (DA) 0.01 ERG, DA 3.0 ERG, DA oscillatory potentials, light-adapted (LA) 3.0 ERG, and 30 Hz flicker ERG.

Main Results:

• Delayed DA oscillatory potentials observed in healthy subjects compared to diabetic patients without DR (p=0.027).
• Significant delays in DA 0.01 "b"-wave, DA 3.0 "b"-wave, and LA 3.0 "a"-wave were found between non-proliferative and pre-proliferative DR groups (p<0.05).
• Progressive delays in LA 3.0 ERG "b"-wave, LA 30 Hz flicker ERG "a"- and "b"-waves were noted between pre-proliferative and proliferative DR groups (p<0.0001 for LA 3.0 "b"-wave).

Conclusions:

• Electrophysiological findings indicate substantial neural retina dysfunction in all stages of DR.
• ERG latency changes serve as a sensitive indicator of DR progression.
• These results highlight the neurodegenerative nature of DR and its impact on retinal function.