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Examination of Anatomical Features of Retinal Ganglion Cells Under N-methyl-D-aspartic Acid (NMDA)-induced Excitotoxicity
Published on: September 19, 2025
Intrinsically photosensitive (melanopsin) retinal ganglion cell function in glaucoma
Beatrix Feigl1, Dietmar Mattes, Ravi Thomas
1Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia. b.feigl@qut.edu.au
Investigative Ophthalmology & Visual Science
|April 19, 2011
Summary
Glaucoma, particularly advanced stages, impairs intrinsically photosensitive retinal ganglion cell (ipRGC) function, as measured by the post-illumination pupil response (PIPR). This ipRGC dysfunction may serve as a future indicator of glaucoma progression.
Area of Science:
- Ophthalmology
- Neuroscience
- Cell Biology
Background:
- Glaucoma is a leading cause of irreversible blindness.
- Retinal ganglion cells (RGCs) are crucial for visual information processing.
- Intrinsically photosensitive RGCs (ipRGCs) possess unique phototransduction capabilities.
Purpose of the Study:
- To investigate alterations in ipRGC function in patients with glaucoma.
- To determine if glaucoma severity correlates with ipRGC dysfunction.
Main Methods:
- Directly measured ipRGC function using the sustained post-illumination pupil response (PIPR).
- Compared PIPR amplitude and kinetics between healthy controls and patients with early and advanced glaucoma using blue and red light stimuli.
- Utilized infrared pupillometry to record consensual pupil responses.
Main Results:
- A significantly smaller blue light-induced PIPR was observed in advanced glaucoma patients compared to normal participants and those with early glaucoma.
- No significant differences in PIPR kinetics were found between groups.
- No significant differences were detected between normal participants and early glaucoma patients, or when combining all glaucoma patients.
Conclusions:
- Moderate to severe glaucoma is associated with ipRGC dysfunction, evidenced by a reduced PIPR.
- The PIPR may serve as a potential clinical biomarker for monitoring glaucoma progression.
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