Objective:

Describe a case of light-induced amaurosis fugax (LIAF) as an uncommon manifestation of carotid disease to decrease treatment delays due to unfamiliarity.  

Background:

Light-induced amaurosis fugax, presents as painless, transient visual obscuration in one or both eyes following exposure to bright light. Unlike other vascular causes of transient vision loss, such as typical amaurosis fugax (AF) or central retinal artery occlusion (CRAO), which often stem from embolic events, LIAF is linked to hypoperfusion of the ophthalmic artery. This results in a delayed recovery of photoreceptors manifesting as impaired visual recovery.  To our knowledge, 25 cases have been reported in the literature: Fourteen with bilateral internal carotid artery (ICA) disease, one ipsilateral ICA and concomitant external carotid artery (ECA) disease, the remaining with variably described disease, including ICA disease at vessel origin. Here we demonstrate an additional case of bilateral ICA disease resulting in LIAF. 

Design/Methods:

N/A

Results:

A 75-year-old female with past medical history of poorly-controlled type 2 diabetes, hyperlipidemia, and uncontrolled hypertension had described symptoms of left eye floaters and discomfort in bright light that had been ongoing for a few months. Carotid ultrasound and subsequent angiogram showed bilateral ICA stenosis of > 70%. The patient underwent successful left internal carotid endarterectomy (CEA) and was discharged home with aspirin and evolocumab. On follow-up one month later, the patient reported no further incidence of visual changes. 

Conclusions:

LIAF is an overlooked etiology for transient vision changes and given critical vessel disease, may herald further cerebrovascular events. Majority of the cases in the literature have described bilateral ICA disease, systems of care should involve prompt bilateral carotid vascular imaging to rule out critical stenosis in any carotid artery which could translate to alternative targets for revascularization. As in our case perfusion can be corrected with CEA for resolution of symptoms.