Overview
Non-arteritic ischemic optic neuropathy (NAION) is a condition characterized by sudden vision loss due to insufficient blood flow to the optic nerve without evidence of large vessel disease. It predominantly affects the optic nerve head, often presenting unilaterally but can occur bilaterally in certain scenarios 12.Diagnosis
Clinical Presentation: Sudden, painless vision loss, often asymmetric 12.
Fundus Examination: Optic disc swelling (papilledema) without hemorrhages 1.
OCT-Angiography: Reduced peripapillary and papillary microvascular density and perfusion, particularly in temporal sectors, observed in acute and resolving stages 1.
Risk Factors: Hypertension, diabetes, sleep apnea, and vascular compromise (e.g., "disc at risk") 13.
Differential Diagnosis: Exclude other causes of optic neuropathy, including arteritic forms 1.Management
No Specific Pharmacological Cure: Supportive care and management of risk factors 13.
Control Underlying Conditions: Tight control of hypertension and diabetes 13.
Avoid Vasoconstrictive Agents: Refrain from using phenylephrine for pupil dilation to prevent potential worsening of visual function 3.
Monitoring: Regular follow-up with visual acuity assessments and OCT to monitor progression 1.Special Populations
Hormonal Therapy: Excessive estrogen dosage in transsexual women may be associated with bilateral NAION 2.
Comorbidities: Patients with systemic conditions like lupus may have NAION secondary to underlying vasculitis 3.Key Recommendations
Utilize OCT-angiography to assess microvascular changes in acute and resolving stages of NAION for monitoring and research purposes (Evidence: Moderate) 1.
Avoid the use of phenylephrine for pupil dilation in patients with NAION due to potential vasoconstrictive effects that may exacerbate visual loss (Evidence: Weak) 3.
Closely manage and monitor cardiovascular risk factors such as hypertension and diabetes to mitigate NAION risk (Evidence: Moderate) 13.
Consider potential hormonal influences, especially high estrogen levels, in transsexual patients undergoing hormone therapy (Evidence: Weak) 2.References
1 Castelain J, Romdhane K, Aptel F, Pollet-Villard F, Attoui O, Bailly S et al.. A case-control study of peripapillary microvascular structure by OCT-angiography in non-arteritic ischaemic optic neuropathy at early and resolutive stages. Eye (London, England) 2025. link
2 Wierckx K, De Zaeytijd J, Elaut E, Heylens G, T'Sjoen G. Bilateral non-arteritic ischemic optic neuropathy in a transsexual woman using excessive estrogen dosage. Archives of sexual behavior 2014. link
3 Pless M, Friberg TR. Topical phenylephrine may result in worsening of visual loss when used to dilate pupils in patients with vaso-occlusive disease of the optic nerve. Seminars in ophthalmology 2003. link