A new method to quantify the human visual threshold from melanopsin sensitive ganglion cells

Area of Science:

• Ophthalmology
• Neuroscience
• Photobiology

Background:

• Traditional photoreceptors (rods and cones) use retinal and opsins for vision.
• Intrinsically photosensitive retinal ganglion cells (ipRGCs) in the inner retina use melanopsin to detect blue light.
• ipRGCs regulate circadian rhythms, pupillary light reflex, sleep, alertness, and mood.

Purpose of the Study:

• To develop a clinically expedient method for measuring the full-field visual threshold of human ipRGCs.
• To expand the ability to detect, diagnose, and monitor ocular and neurologic diseases.
• To provide a global retinal metric of ipRGCs as an outcome measure for gene therapy studies.

Main Methods:

• Utilized selective chromatic adaptation (blue stimulus on an amber field) to suppress rod and cone input.
• Incorporated a filter to block input from blue-sensitive cones.
• Developed a method to measure the putative visual threshold from human ipRGCs.

Main Results:

• A novel method was established to isolate and measure ipRGC visual function.
• This technique allows for the assessment of ipRGCs independent of rod and cone input.
• The developed metric shows potential for clinical application in disease monitoring.

Conclusions:

• The new method provides a clinically relevant measure of ipRGC visual function.
• This metric can aid in the diagnosis and management of various ocular and neurological conditions.
• It offers a potential outcome measure for evaluating vision restoration therapies.