EC Ophthalmology

Existing methods for measuring functional vision in low-vision individuals may not capture clinically meaningful outcomes. The Multi-luminance Y-Mobility Test (MLYMT) is developed to assess the ability to navigate around obstacles lighted at various luminance levels and accurately touch randomly switched lighted panels by individuals with severe vision loss, especially in the periphery. This test is designed to measure the patient's ability to navigate at different light levels, providing valuable information about the progression of as well as evaluating therapeutic efficacy. MLYMT seeks to gauge severe-vision loss subjects' visually guided navigational skills and their ability to effectively move through a course, making informed decisions while encountering obstacles at varying lighting conditions. MLYMT assay evaluates the ability of a subject to navigate under different luminance levels, which is relevant to patients suffering from photoreceptor degeneration. The assay's multi-luminance design aligns with clinical standards, enabling meaningful interpretation of outcomes within a clinical context and facilitating comparisons with existing benchmarks in the field of functional vision assessment. By incorporating a simple Y-shaped configuration of light panels and light-scattering large obstacles, the MLYMT aims to create a controlled, yet real-life environment that simulates everyday scenarios of luminance-gradient encountered by individuals with severe vision loss. The assay focuses on participants' ability to adapt to changing luminance levels (while navigating in a luminance gradient) and make navigation decisions based on visual cues and obstacles, mirroring the different real-world environments. The MLYMT can serve as a standard tool for monitoring and quantifying functional vision changes over time, allowing for evaluation of the impact of interventions aimed at enhancing the subject's vision. Overall, the MLYMT represents a promising new approach for the evaluation of functional vision in severe vision loss patients.

 Keywords: Multi-Luminance Y-Mobility Test; Vision Assessment Tool; Low Vision; Functional Vision Assessment; Vision Guided Navigation

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