In Vivo Macro-Micro Neurovascular Mapping and Visual Field Correspondence in Non-Arteritic Anterior Ischemic Optic Neuropathy.

INTRODUCTION

This study aimed to establish an in vivo neurovascular staging framework for non-arteritic anterior ischemic optic neuropathy (NAION) by integrating wide-field swept-source optical coherence tomography angiography (SS-OCTA) and adaptive optics scanning laser ophthalmoscopy (AOSLO), enabling precise mapping of visual field (VF) defects.

METHODS

This prospective study enrolled 22 acute NAION eyes (≤ 3 weeks), 27 chronic NAION eyes (≥ 3 months), and 20 age-/sex-matched healthy controls. SS-OCTA (12 × 12 mm) quantified peripapillary and pan-retinal nerve fiber layer (RNFL) thickness and vessel density (VD) corresponding to VF defect location. AOSLO assessed axonal grading and photoreceptor integrity. Multivariable linear regression was performed to identify independent predictors of visual function.

RESULTS

Within VF defect regions, acute cases showing widespread RNFL swelling, vascular dilation, and VD increase in the temporal sector and intermediate capillary plexus (ICP), chronic cases exhibiting axonal thinning and a nasal-to-temporal capillary attenuation (adj-P < 0.05). Deep capillary plexus (DCP) VD was an independent predictor of acute visual function, whereas chronic visual function was primarily determined by macular ganglion cell thickness and optic disc perfusion. AOSLO confirmed acute axonal edema with hyperreflective dot-like foci (HDF) and chronic atrophy with vessel narrowing (adj-P < 0.05), while photoreceptors remained preserved (P > 0.05).

CONCLUSIONS

Wide-field SS-OCTA and AOSLO delineate the stage-specific neurovascular cascade of NAION. Acute NAION is characterized by DCP VD serving as an independent biomarker of visual functional impairment, alongside axonal swelling and early imaging features (e.g., HDF). In the chronic stage, visual outcome is primarily determined by macular neuro-axonal loss and progressive capillary attenuation.