NAION
Medical abbreviation · Ophthalmology & ENT
| Stands for | Nonarteritic anterior ischemic optic neuropathy |
|---|---|
| Categories | Medical |
NAION stands for Nonarteritic anterior ischemic optic neuropathy, an ophthalmology & ENT abbreviation.
Sudden, painless vision loss in one eye from reduced blood flow to the front of the optic nerve, the most common acute optic neuropathy in adults over 50. Typical findings are a swollen optic disc and a field defect, often in the lower half.
Example: Painless inferior field loss OS on waking, swollen disc, ESR normal: NAION.
Usage notes
A small, crowded optic disc with little or no cup ("disc at risk") is a key anatomical risk factor, along with hypertension, diabetes and sleep apnea. In 2025 the European Medicines Agency concluded that NAION is a very rare side effect of semaglutide. Giant cell arteritis must be excluded because it causes the arteritic form, which needs urgent steroids.
Related abbreviations
More ophthalmology & ENT abbreviations
- ICL – Implantable collamer lens
- IOP – Intraocular pressure
- LP – Light perception
- LPI – Laser peripheral iridotomy
- LPR – Laryngopharyngeal reflux
- MGD – Meibomian gland dysfunction
- NIHL – Noise-induced hearing loss
- NLP – No light perception
- NPC – Nasopharyngeal carcinoma
- NPDR – Nonproliferative diabetic retinopathy
- NTG – Normal-tension glaucoma
- OAE – Otoacoustic emissions
See all 74 ophthalmology & ENT abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.