In amaurosis fugax, there is a sudden loss of vision in one eye. Patients gain their vision after a few minutes. The most common underlying cause is atherosclerosis of the internal carotid artery. Other underlying causes include vasospasm of the internal carotid artery, which leads to hypoperfusion and is seen in vasculitis, ocular migraines, and systemic lupus erythematosus. In this case study, a 44-year-old male with a past medical history of migraine with aura presented to the emergency room with transient vision loss in the left eye, which lasted for two minutes. A computed tomography scan of the brain was negative for stroke. The patient was treated with intravenous fluid, aspirin, and enoxaparin sodium and instructed to follow up with neurology. A medical emergency such as amaurosis fugax caused by ocular migraine must be managed aggressively, and prompt imaging is necessary to exclude other causes.

We describe an unusual case of a 73-year-old man with amaurosis fugax. He had repeated transient monocular symptoms, one of which features lighting bolt-shaped glittering in the full visual field of the right eye since medical treatment for hypertension and diabetes mellitus started. A few days later, he felt difficulty in speech as well as sensory and motor disturbance in the left upper extremity, which finally brought him to our hospital. An MR scan unveiled subacute infarctions dotted in the right cerebral hemisphere and severe carotid stenosis on the same side with a delayed distal flow. He was hospitalised with diagnosed an ischemic stroke. Despite being treated with antithrombotic agents, he had suffered similar visual symptoms repeatedly and therefore, carotid artery stenting was performed on Day 16 starting from the onset. The right ophthalmic artery and choroidal crescent became depicted angiographically after our surgery had been completed. His visual disturbance has never appeared since then. Consequently, it is suggested that the optic disorders were attributed to a hemodynamically precarious state in the area of the ophthalmic artery.

Sarcoidosis is a chronic multisystemic disease, which can be rarely associated with autoimmune disorders, such as antiphospholipid syndrome (APS). Although amaurosis fugax is an uncommon complication, its presentation can unmask a carotid artery dissection (CAD) in these diseases. In addition, central serous chorioretinopathy (CSC) has been related to vascular disorders too. We presented a case of a Caucasian middle-aged man, who developed CAD symptoms, such as amaurosis fugax in the right eye (RE) and headache. His medical history included arterial hypertension, hypothyroidism, and Lofgren's syndrome. On examination, retinal pigment epithelium (RPE) atrophy and subretinal fluid (SRF) in the macular area of the RE were observed. These findings were confirmed by optical coherence tomography (OCT), which also revealed an increase in choroidal thickness. However, these differed significantly from the contralateral eye. These clinical symptoms and imaging findings suggested a CSC in the RE, but not all clinical processes were justified. Subsequently, a CT angiography was performed and confirmed a significant occlusion in the right internal carotid artery and progressive sharpening of the lumen with an intimal flap due to a carotid dissection. In addition, the laboratory results were compatible with antiphospholipid syndrome (APS). To the authors' knowledge, the patient returned to the ED due to an anterior uveitis and he is currently asymptomatic with Cemidon and Adalimumab treatment. We described for the first time a case of carotid dissection and central serous chorioretinopathy in the context of two autoimmune-based pathologies, such as sarcoidosis and antiphospholipid syndrome. Abbreviations: APS = Antiphospholipid syndrome, BCVA = Best-corrected visual acuity, CAD = Carotid artery dissection, CNV = Choroidal neovascular membrane, CSC = Central serous chorioretinopathy, CT = Computed tomography, ED = Emergency Department, ICAD = Internal carotid artery dissection, LE = Left eye, OCT = Optical coherence tomography, RAPD = Relative afferent pupillary defect, RPE = Retinal pigment epithelium, RE = Right eye, SRF = Subretinal fluid.

The ophthalmic artery is the first branch of the internal carotid artery. It comes off just distal to the cavernous sinus. The ophthalmic artery gives off many branches, which supply the orbit, meninges, face, and upper nose. When the ophthalmic artery is occluded, it can compromise vision. The ophthalmic artery comes off the internal carotid artery on the medial side of the anterior clinoid process and traverses anteriorly through the optic canal and just lateral to the optic nerve.[1][2][3] The following are branches of the ophthalmic artery: 1. The first branch of the ophthalmic artery is the central retinal artery that runs in the dura mater of the optic nerve. It then moves further along and supplies the inner layers of the retina. 2. The second and the largest branch of the ophthalmic artery is the lacrimal artery. It also enters the orbit and traverses along the superior edge of the lateral rectus muscle. It supplies the eyelids, lacrimal gland, and conjunctiva. 3. The ophthalmic artery gives off several posterior ciliary arteries that pass through the sclera and supply the posterior uveal tract. Because the posterior ciliary vessels are end vessels, sudden occlusion can produce infarction in the region of the choroid. 4. The ophthalmic artery also gives off the inferior and superior muscular vessels that supply the extraocular muscles. The supraorbital artery is also a branch of the ophthalmic artery and passes through the supraorbital foramen to supply the skin of the forehead and Levator palpebrae muscle. 5. Other branches of the ophthalmic artery include the ethmoid arteries, medial palpebral vessels, and terminal branches.  When there is occlusion of the ophthalmic artery, it can result in an ischemic syndrome. Amaurosis fugax is a condition associated with temporary, painless loss of vision due to either an embolic phenomenon or hypoperfusion. Emboli to the ophthalmic artery usually originate from the carotid artery bifurcation. One may visualize Hollenhorst bodies (a.k.a., Eickenhorst plaques) in the retina during fundoscopic evaluation. When there is a sudden, painless loss of vision in one eye, it is recommended that one obtain a duplex ultrasound of the neck to assess the carotid artery for atherosclerotic plaques.[4][5][6]

The term amaurosis fugax is often used interchangeably to describe transient visual loss (TVL). However, it is employed widely in medicine to refer to any cause of transient monocular visual loss. Here, we will refer to amaurosis fugax only in the context of transient monocular visual loss associated with vascular thromboembolic events arising from the internal carotid arterial system. [1],[2],[3] The condition is not common in children and more likely to have a benign cause. In adults, in most cases, the cause is atherosclerotic emboli from the carotid artery bifurcation.

Determining the difference between hemodynamic and embolic stroke in the presence of chronic internal carotid artery occlusion is important. Embolic symptoms may be from classic stroke or transient ischemic attack (TIA). Symptoms may include a contralateral motor or sensory deficits as well as amaurosis fugax. Hemodynamic symptoms may be similar to a classic stroke or TIA, but may also be less predictable and atypical. Patients have reported symptoms such as limb shaking, retinal claudication, headache from large pulsatile external carotid artery collaterals, syncope, and generalized fatigue. One-third of all strokes are related to cervical carotid disease. Standard risk factors for coronary and systemic atherosclerosis such as age, male sex, family history, smoking, hypertension, hyperlipidemia, sedentary lifestyle, and high dietary fat apply to this patient population. The mechanism of cervical carotid stroke is usually embolization from the carotid bifurcation plaque, but hemodynamic compromise from stenosis may also play a role. The risks of embolization and hemodynamic compromise increase with increasing carotid artery stenosis.

Symptoms of extracranial carotid disease are most often caused by embolization. Arterial emboli account for approximately one-quarter of strokes in Europe and North America, and 80% of these originate from atherosclerotic lesions in a surgically accessible artery in the neck. The most common lesion is at the bifurcation of the carotid artery. Transcranial Doppler studies have shown that emboli are seen in approximately 20% of patients with moderate (> 50% stenosis) lesions at the carotid bifurcation and even higher rates with more than 70% stenoses. The incidence and frequency of emboli are increased in recently symptomatic patients. The neurologic dysfunction associated with microemboli may appear as sudden or transient, neurologic symptoms that may include unilateral motor and sensory loss, aphasia (difficulty finding words), or dysarthria (difficulty speaking due to motor dysfunction). These are termed Transient Ischemic Attack (TIA). Most TIAs are brief (minutes). By convention, 24 hours is the arbitrary limit of a TIA. If the symptoms persist, it is a stroke, or cerebrovascular accident (CVA). An embolus to the ophthalmic artery, the first branch of the internal carotid artery, produces a temporary monocular loss of vision called amaurosis fugax or permanent blindness.  Lesions of atherosclerosis in the internal carotid artery occur along the wall of the carotid bulb opposite to the external carotid artery origin. The enlargement of the bulb just distal to this major branch point creates an area of low wall shear stress, flow separation, and loss of unidirectional flow. Presumably, this allows greater interaction of atherogenic particles and the vessel walls at this site and accounts for the localized plaque at the carotid bifurcation. The accessibility of this localized atheroma allows effective removal of the plaque and a dramatic reduction in stroke risk. Without treatment, 26% of patients with TIAs and more than 70% with carotid artery stenosis will develop permanent neurological impairment (CVA)  from continued embolization at two years. The risk of CVA can be reduced to 9% with plaque removal and is usually lower for a patient presenting with amaurosis fugax. 

There are many causes of amaurosis fugax, including polycythemia. Polycythemia is associated with elevated hematocrit levels and hyperviscosity, which can lead to ocular manifestations. We report a polycythemia patient with amaurosis fugax, who had resolution of ocular symptoms following venesection. A 29-year-old gentleman presented with a six-month history of episodic bilateral transient loss of vision (amaurosis fugax), followed by slow recovery back to normal after 15-20 minutes. The symptoms worsened with fatigue. He also had an unsteady gait for the preceding one year. Ocular examination was unremarkable. His visual acuity was 20/20 OU. Neurological examination revealed gait ataxia and dysdiadochokinesia. Computed tomography (CT) angiogram showed an old cerebellar infarct. Blood investigations showed persistent elevated hemoglobin and hematocrit with positive JAK-2 V617F mutation. Infective and connective tissue workups were all negative. A diagnosis of polycythemia was made by the haematology team. In addition to oral aspirin given by the neurology team, he underwent venesection with improvement in ocular symptoms following each episode of venesection. The frequency of amaurosis fugax reduced from 2-3 episodes a week to once a month, then resolved completely after five venesections. Systemically, his cerebellar symptoms also resolved and there were no neurological deficits. Polycythemia is a rare disease that can cause amaurosis fugax and thrombotic events in young patients. Better knowledge and accurate diagnosis are important, as early treatment may improve the symptoms and long-term morbidity.

Visual complications represent common deficits following surgical or endovascular repair of paraclinoid aneurysms. Different etiologies should be investigated to prevent devastating consequences. Herein we present a point-of-care evaluation to investigate sudden visual loss after coiling of paraclinoid aneurysms. A 20-year-old male was admitted for a sudden headache. Head computed tomography showed a subarachnoid hemorrhage and subsequent angiography revealed a 9-mm left supraclinoid aneurysm of the internal carotid artery treated with endovascular coil embolization. Thirty minutes after intensive care unit admission, the patient reported a left amaurosis. To exclude secondary etiologies, an immediate evaluation with point-of-care devices (color-doppler and B-mode ultrasound and automated pupillometry) was performed. Sonographic evaluations were negative for ischemic/thrombotic events and neurologic pupil index within physiological ranges provide evidence of third cranial nerve responsiveness. The symptomatology resolved progressively over 120 minutes with low-dose steroid therapy, 30° head-of-bed elevation, and blood pressure management. Visual deficits can occur after endovascular procedure and should be investigated. Suspected visual loss is a neurological emergency that deserves a prompt evaluation. Ultrasound and automated pupillometry have proved to be an effective, rapid, reliable, and non-invasive combination for a clinical decision-making strategy in the management of post-procedural acute visual deficits.

Background MRI and fluorine 18-labeled sodium fluoride (18F-NaF) PET can be used to identify features of plaque instability, rupture, and disease activity, but large studies have not been performed. Purpose To evaluate the association between 18F-NaF activity and culprit carotid plaque in acute neurovascular syndrome. Materials and Methods In this prospective observational cohort study (October 2017 to January 2020), participants underwent 18F-NaF PET/MRI. An experienced clinician determined the culprit carotid artery based on symptoms and record review. 18F-NaF uptake was quantified using standardized uptake values and tissue-to-background ratios. Statistical significance was assessed with the Welch, χ2, Wilcoxon, or Fisher test. Multivariable models were used to evaluate the relationship between the imaging markers and the culprit versus nonculprit vessel. Results A total of 110 participants were evaluated (mean age, 68 years ± 10 [SD]; 70 men and 40 women). Of the 110, 34 (32%) had prior cerebrovascular disease, and 26 (24%) presented with amaurosis fugax, 54 (49%) with transient ischemic attack, and 30 (27%) with stroke. Compared with nonculprit carotids, culprit carotids had greater stenoses (≥50% stenosis: 30% vs 15% [P = .02]; ≥70% stenosis: 25% vs 4.5% [P < .001]) and had increased prevalence of MRI-derived adverse plaque features, including intraplaque hemorrhage (42% vs 23%; P = .004), necrotic core (36% vs 18%; P = .004), thrombus (7.3% vs 0%; P = .01), ulceration (18% vs 3.6%; P = .001), and higher 18F-NaF uptake (maximum tissue-to-background ratio, 1.38 [IQR, 1.12-1.82] vs 1.26 [IQR, 0.99-1.66], respectively; P = .04). Higher 18F-NaF uptake was positively associated with necrosis, intraplaque hemorrhage, ulceration, and calcification and inversely associated with fibrosis (P = .04 to P < .001). In multivariable analysis, carotid stenosis at or over 70% (odds ratio, 5.72 [95% CI: 2.2, 18]) and MRI-derived adverse plaque characteristics (odds ratio, 2.16 [95% CI: 1.2, 3.9]) were both associated with the culprit versus nonculprit carotid vessel. Conclusion Fluorine 18-labeled sodium fluoride PET/MRI characteristics were associated with the culprit carotid vessel in study participants with acute neurovascular syndrome. Clinical trial registration no. NCT03215550 and NCT03215563 © RSNA, 2022 Online supplemental material is available for this article.

Carotid stump syndrome (CSS) is a rare cause of recurrent ipsilateral cerebrovascular events that typically manifests as transient ischemic attacks or amaurosis fugax. The cause of these recurrent symptoms is thought to be microembolization from an occluded internal carotid artery that reaches intracranial circulation through anastomoses. We undertook a systematic literature review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the PubMed, Web of Science, and Embase databases of the endovascular treatment options for CSS. Nine papers met the inclusion criteria and provided patient data on 12 patients, and one case illustration is presented. Treatment was with common carotid artery-external carotid artery stent graft without concomitant coil embolization in nine patients and with coil embolization without stenting, the breakthrough of the stump with a wire and subsequent internal carotid artery stent placement, and stent-assisted coil embolization in one patient each. During a median follow-up of six months, all patients were on dual antiplatelet therapy except one on undefined "systemic anticoagulation." Twelve patients had no symptoms after treatment, one had transient expressive aphasia but no further symptoms after being placed on anticoagulation, and none had intraprocedural complications or had to undergo retreatment. Our review indicates that endovascular treatment of CSS is associated with low intraprocedural risk and is effective at treating recurrent symptoms.

Visual disturbances in Takayasu arteritis (TA) are common but tend to be late manifestations of the disease. However, its presence at diagnosis must alert TA to avoid sight disabilities. Herein, we present two children with TA that debuted with vision loss, and the results of the literature review displayed 58 subjects with vision loss before the diagnosis of TA. The world English literature was reviewed by searching the PubMed database of the National Library of Medicine for the terms "Takayasu Arteritis" and "Blindness" or "Amaurosis fugax", from 190 to 2021. Cases eligible must present vision loss before or at TA diagnosis. Our two patients who presented with amaurosis fulfilled the criteria for TA diagnosis. The first patient had a bilateral and transient visual loss, whereas the second had monocular and permanent amaurosis. Both patients were cursed with hypertension and demonstrated large vessel compromise; their clinical picture improved with corticosteroids and immunosuppressant therapy. We identified in the literature review sixteen patients with TA in case reports and 42 in case series, plus our two cases presented herein with monocular or bilateral vision loss at the time of diagnosis. Previous literature indicated that amaurosis represents a severely advanced disease. Herein, we reported two children with amaurosis as their pivotal symptom; they had significant head and neck vascular alterations, so prompt and aggressive treatment is needed to prevent disease progression and disability. Transient or permanent vision loss must alert the physician to include Takayasu arteritis in the differential diagnosis.

Oxaliplatin, a third-generation platinum-based agent, is a constitutive part of systemic treatment for colorectal cancer in adjuvant and metastatic settings. Ocular toxicity is an extremely rare adverse effect of Oxaliplatin. Ocular toxicities have been documented in the form of (a) common (≥1/100, <1/10) which include the conjunctivitis, unexpected lacrimation, blurry vision, blepharoptosis, and (b) uncommon (≥1/10,000, <1/1,000) which compromise the tunnel vision, idiosyncratic color perception, transient bilateral visual loss, and rarest phenomenon of Amaurosis fugax. Amaurosis fugax implies to any cause of transient, painless, unilateral visual loss; with the possible underlying mechanism of thrombo-embolic carotid plaque, hypoperfusion, or vasospasm of retinal vessels, due to hyperviscosity, and atherosclerotic vascular disease. To date, only a few case reports of Oxaliplatin-induced Amaurosis fugax have been published. We here-in report 3 cases who experienced Amaurosis fugax while receiving Oxaliplatin in our one of health board-based four hospitals.