During follow-up for optic nerve head drusen, which assessment is primarily used to ensure vision is not affected?

• A. Visual field testing
• B. Color vision testing
• C. Intraocular pressure measurement
• D. Fundus photography

Answer: (A)

Monitoring vision in optic nerve head drusen focuses on detecting whether the visual field is affected. Drusen are calcified deposits in the optic nerve head that can compress nerve fibers over time, potentially leading to subtle or progressive field loss even when central acuity remains good. Visual field testing, especially automated perimetry, directly measures how well you see across the entire field of view and can reveal scotomas or patterns of loss that signal functional impact on vision. This makes it the primary tool for ensuring vision isn’t being compromised during follow-up.

Color vision testing is less reliable for tracking drusen-related changes and is not the main method used to monitor functional vision in this condition. Intraocular pressure measurement assesses glaucoma risk rather than directly evaluating optic nerve-related vision, and fundus photography documents anatomy and structural changes but does not quantify how vision functions across the field.