Retinal structural changes in Parkinson's disease: differences in pRNFL thickness between GBA1-associated and...

Area of Science:

• Ophthalmology
• Neurology
• Genetics

Background:

• Retinal structural changes are potential biomarkers for neurodegeneration in Parkinson's disease (PD).
• Reduced Retinal Nerve Fiber Layer (pRNFL) thickness is observed in PD patients.
• Differences between idiopathic PD and GBA1-associated PD (GBA-PD) regarding retinal structure are under-explored.

Purpose of the Study:

• To investigate differences in pRNFL thickness between GBA-PD and non-mutated PD (NM-PD).
• To explore associations between retinal thickness and clinical variables in different PD genotypes.

Main Methods:

• Observational study of 59 PD patients (32 GBA-PD, 27 NM-PD).
• Clinical assessment included MoCA, MDS-UPDRS, and Hoehn-Yahr.
• Spectral-domain OCT measured pRNFL thickness across six sectors and three diameters.

Main Results:

• NM-PD patients had significantly thinner temporal pRNFL sectors compared to GBA-PD patients.
• In NM-PD, thinner temporal-superior pRNFL correlated with MoCA scores, and nasal-inferior pRNFL correlated with MDS-UPDRS part-IV.
• No significant associations between pRNFL thickness and clinical variables were found in GBA-PD.

Conclusions:

• Distinct retinal thickness patterns exist between GBA-PD and NM-PD, suggesting different pathophysiological mechanisms.
• Sector-specific pRNFL thickness in NM-PD correlates with cognitive impairment and motor complications.
• Retinal imaging may provide insights into genotype-specific neurodegeneration and clinical manifestations in PD.