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Updated: May 29, 2026
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The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy (rNAION)
Published on: November 20, 2016
Bilateral simultaneous anterior ischemic optic neuropathy associated with sildenafil
Marilita M Moschos1, Ioannis Margetis
1Department of Ophthalmology, University of Athens, Athens, Greece.
Case Reports in Ophthalmology
|September 24, 2011
Summary
This case study details a man who developed simultaneous bilateral nonarteritic anterior ischemic optic neuropathy (NAION) after using sildenafil. Discontinuation of the drug led to vision improvement, though some visual field defects persisted.
Area of Science:
- Ophthalmology
- Neurology
- Pharmacology
Background:
- Nonarteritic anterior ischemic optic neuropathy (NAION) is a common cause of optic nerve damage.
- Sildenafil is a phosphodiesterase-5 inhibitor used for erectile dysfunction.
Observation:
- A 55-year-old man presented with simultaneous bilateral NAION after 8 months of regular sildenafil use.
- Initial visual acuity was reduced, with inferior altitudinal visual field defects and optic disc edema observed.
Findings:
- Sildenafil discontinuation resulted in improved visual acuity and resolved optic disc edema.
- Persistent visual field defects were noted in one eye despite treatment.
Implications:
- This case highlights a potential association between sildenafil use and bilateral NAION.
- Further research is warranted to understand the risk factors and mechanisms involved.
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