Outer Retinal Layer Thickness Changes in White Matter Hyperintensity and Parkinson's Disease.

Area of Science:

• Ophthalmology
• Neurology
• Medical Imaging

Background:

• White matter hyperintensities (WMH) and Parkinson's Disease (PD) are significant neurological conditions.
• Understanding ocular manifestations can provide insights into neurodegenerative processes.
• Outer retinal layers are crucial for visual function and may reflect underlying brain pathology.

Purpose of the Study:

• To investigate outer retinal layer thickness variations in patients with WMH and PD compared to healthy controls (HC).
• To explore the potential of these retinal changes as biomarkers for neurological diseases.

Main Methods:

• Spectral-domain optical coherence tomography (SD-OCT) was used for macular imaging.
• A deep learning algorithm was employed for accurate segmentation of retinal layers.
• Thickness measurements of specific outer retinal layers were quantified.

Main Results:

• WMH patients exhibited thinner Henle fiber layers/outer nuclear layers (HFL+ONL) and photoreceptor outer segments (OS) compared to HC.
• PD patients showed increased thickness in the interdigitation zone/retinal pigment epithelium/Bruch complex (IZ+RPE).
• No significant differences were found in other measured retinal layers between groups.

Conclusions:

• Alterations in HFL+ONL, OS, and IZ+RPE layer thickness may be associated with WMH and PD.
• These retinal layer thickness changes could serve as potential biomarkers for detecting certain brain-related diseases.
• Further longitudinal studies are recommended to validate these findings.