Contrast Acuity With Different Colors in Parkinson's Disease

Area of Science:

• Ophthalmology
• Neurology
• Medical Technology

Background:

• Abnormal color vision and contrast acuity significantly impact daily life.
• Parkinson's disease (PD) is a neurodegenerative disorder affecting motor function and potentially sensory perception.
• Assessing visual function is crucial for understanding the multifaceted effects of PD.

Purpose of the Study:

• To evaluate color visual acuity at high and low contrast in individuals with Parkinson's disease (PD) and control groups.
• To assess the utility of an iPad application for measuring color vision in PD.
• To investigate potential differences in color perception between PD patients and healthy controls.

Main Methods:

• Color visual acuity was tested using the Variable Contrast Acuity Chart on an iPad.
• Five colors (red, green, blue, yellow, black) were assessed at low (2.5%) and high (100%) contrast.
• A numerical score was assigned based on correctly identified colors, with statistical analysis adjusting for age and sex.

Main Results:

• Parkinson's disease patients demonstrated significantly lower color vision scores compared to controls at both high and low contrasts (except for yellow at low contrast).
• The largest effect size was observed for yellow at high contrast.
• The iPad application showed high specificity (97%) and positive predictive value (92%) for detecting color vision deficits in PD.

Conclusions:

• An iPad-based application may serve as a user-friendly biomarker for color vision assessment in Parkinson's disease.
• Further research is warranted to establish disease specificity and explore its role in monitoring disease progression and treatment.
• Investigating prodromal PD detection using this visual biomarker is a potential future direction.