Transient monocular visual loss

Transient Monocular Visual Loss (Amaurosis Fugax): How Does Age Impact Diagnosis?

Transient monocular visual loss (TMVL), also known as transient monocular blindness or amaurosis fugax ("fleeting blindness"), is a temporary loss of vision often due to ischemia to the retina. While acute TMVL should be considered an emergency that further requires exhaustive investigation, there are some cases in which TMVL arises secondary to benign causes. Age has a major impact in the diagnosis of ischemia and although the differential diagnosis of TMVL can be broad, timely and appropriate history, examination, diagnostic testing, and treatment can be vision- or life-saving. We review the causes of TMVL and the impact of age on the differential diagnoses and management.

Presenting Symptoms and Diffusion-Weighted MRI Positivity by Time After Transient Neurologic Events: A Pooled Analysis of 3 Cohort Studies

BACKGROUND AND OBJECTIVE

The association between focal vs nonfocal presenting symptom and diffusion-weighted imaging (DWI) positivity in relation to onset-to-imaging time in patients with transient neurologic events remains unclear. We hypothesize that episodes consisting of focal symptoms would have proportionally higher DWI-positive imaging at later onset-to-imaging times.

METHODS

Patients with transient neurologic symptoms and a normal neurologic examination who had DWI in the combined data set of 3 cohort studies were included. We used logistic regression models to evaluate the association between each type of presenting symptom (motor weakness, speech impairment, sensory symptoms, vision loss, diplopia, gait instability, dizziness, headache, presyncope, and amnesia) and DWI positivity after adjusting for clinical variables (age, sex, history of stroke, dyslipidemia, coronary artery disease, atrial fibrillation, symptoms duration [<10, 10-59, ≥60 minutes, or unclear], and study source). We stratified the results by onset-to-imaging time categories (<6 hours, 6-23 hours, and ≥24 hours).

RESULTS

Of the total 2,411 patients (1,345 male, median age 68 years), DWI-positive lesions were detected in 598 patients (24.8%). The prevalence of DWI positivity was highest in those with motor weakness (34.7%), followed by speech impairment (33.5%). In a multivariable analysis, the presence of motor weakness, speech impairment, and sensory symptoms was associated with DWI positivity, while vision loss and headache were associated with lower odds of DWI positivity, but nevertheless had 13.6% and 15.3% frequency of DWI positive. The odds of being DWI positive varied by onset-to-imaging time categories for motor weakness, with greater odds of being DWI positive at later imaging time (<6 hours: odds ratio [OR] 1.25, 95% confidence interval [CI] 0.84-1.87; 6-23 hours: OR 2.24, 95% CI 1.47-3.42; and ≥24 hours: OR 2.42, 95% CI 1.74-3.36; interaction p = 0.033). Associations of other symptoms with DWI positivity did not vary significantly by time categories.

DISCUSSION

We found that onset-to-imaging time influences the relationship between motor weakness and DWI positivity in patients with transient neurologic events. Compared with motor, speech, and sensory symptoms, visual or nonfocal symptoms carry a lower but still a substantive association with DWI positivity.

Yield of Investigations in Young Patients Presenting With Transient Monocular Vision Loss: A Prospective Study

PURPOSE

It is unclear whether transient monocular vision loss (TMVL) warrants the same thorough systemic evaluation for potential embolic sources in young adults as it does in older adults. The objective of the present study was to evaluate the yield of investigations in patients under 45 years of age presenting with TMVL.

DESIGN

Prospective cohort study.

METHODS

Young adult patients with TMVL presenting to a university-affiliated neuro-ophthalmology clinic were included. All included patients were referred for neuroimaging (computed tomography or magnetic resonance angiography of entire carotid tree and magnetic resonance imaging of the brain) and cardiac investigations (transesophageal echocardiography and 2 weeks of Holter monitoring).

RESULTS

A total of 20 participants with TMVL were included in the study. The mean age was 33.1 ± 8.2 years, and 16 of the 20 participants were women. The most common finding on past medical history was migraines, in 5 of 20 cases (25%), and 25% of patients had headaches during their visual loss. Of 17 participants who completed neuroimaging, 1 had fibromuscular dysplasia (this patient also experienced headaches during their symptoms). Two of 13 patients who completed echocardiography had patent foramen ovale. Overall, 3 of 20 participants (15%, 95% CI 3%-38%) had abnormal findings associated with their TMVL. Aspirin treatment was initiated in 2 of 3 patients following investigations.

CONCLUSION

In our cohort of young patients presenting with TMVL, 15% of patients had abnormal findings on further investigations. We recommend that young patients presenting with TMVL be referred for neuroimaging and cardiac workup so that appropriate treatments can be initiated to prevent future complications. Headaches during vision loss may not always indicate a benign cause, and retinal migraine should be a diagnosis of exclusion.

Transient Visual Obscurations Without Papilloedema as the Heralding Symptom of Chiasmal Compression

Transient visual obscurations (TVOs) represent brief ischaemic events of the optic nerve. These most commonly occur in the setting of raised intracranial pressure or more localised aetiologies within the orbit that result in decreased perfusion pressure. Transient vision loss has rarely been associated with pituitary tumours or optic chiasm compression, but details are lacking. We describe classic TVOs that completely resolved following resection of a pituitary macroadenoma causing chiasmal compression with a relatively normal eye examination. Clinicians should consider neuro-imaging in patients with TVOs and a normal evaluation.

The effect of systemic factors on retinal blood flow in patients with carotid stenosis: an optical coherence tomography angiography study

Carotid artery stenosis (CAS) is among the leading causes of mortality and permanent disabilities in the Western world. CAS is a consequence of systemic atherosclerotic disease affecting the majority of the aging population. Optical coherence tomography angiography (OCTA) is a novel imaging technique for visualizing retinal blood flow. It is a noninvasive, fast method for qualitative and quantitative assessment of the microcirculation. Cerebral and retinal circulation share similar anatomy, physiology, and embryology; thus, retinal microvasculature provides a unique opportunity to study the pathogenesis of cerebral small vessel disease in vivo. In this study, we aimed to analyze the effect of systemic risk factors on retinal blood flow in the eyes of patients with significant carotid artery stenosis using OCT angiography. A total of 112 eyes of 56 patients with significant carotid stenosis were included in the study. We found that several systemic factors, such as decreased estimated glomerular filtration rate (eGFR), hypertension, and carotid occlusion have a significant negative effect on retinal blood flow, while statin use and carotid surgery substantially improve ocular microcirculation. Neither diabetes, clopidogrel or acetylsalicylic acid use, BMI, serum lipid level, nor thrombocyte count showed a significant effect on ocular blood flow. Our results demonstrate that a systematic connection does exist between certain systemic risk factors and retinal blood flow in this patient population. OCTA could help in the assessment of cerebral circulation of patients with CAS due to its ability to detect subtle changes in retinal microcirculation that is considered to represent changes in intracranial blood flow.

Ocular ischaemia: signs, symptoms, and clinical considerations for primary eye care practitioners

Ischaemic stroke is a major disease burden as well as a leading cause of death. Early signs of ischaemic stroke can manifest in the eye, placing primary eyecare practitioners in an important position to identify patients at risk of ischaemic stroke and initiate suitable referral pathways. The vascular supply to the brain is reviewed with reference to vision including the various retinal signs and ocular symptoms associated with transient ischaemic attacks and ischaemic stroke. Using a range of clinical cases, the diverse clinical presentations of retinal embolic events, as well as other forms of vascular occlusion, are highlighted and the underlying pathophysiology is discussed. A succinct scheme for the assessment and management of ischaemic events for primary eye care practitioners is provided.

Vascular origin in acute transient visual disturbance: A prospective study

BACKGROUND AND PURPOSE

This study was undertaken to validate a clinical score of vascular origin in patients with acute transient visual disturbances (TVDs) without diplopia.

METHODS

We conducted a prospective study in an ophthalmology emergency department and a transient ischemic attack (TIA) clinic. Patients underwent clinical evaluation including a tailored questionnaire, brain, vascular, and ophthalmologic investigations, and 3-month follow-up. TVDs were classified according to vascular or nonvascular origin by three independent experts based on all clinical, cerebrovascular, and ophthalmologic investigations, but blind to the questionnaire results. A clinical score was derived based on clinical variables independently associated with a vascular origin, and was externally validated in an independent cohort.

RESULTS

An ischemic origin of TVD was found in 45% (67/149) of patients in the derivation cohort. Age and six questions were independently associated with an ischemic origin. A nine-point score (≥70 years old = 2; monocular visual loss = 2; black or white vision = 1; single episode = 1; lack of headache = 2; diffuse, constricted, altitudinal, or lateralized visual loss pattern on drawings = 1) showed good discriminative power in identifying ischemic origin (c-statistic = 0.82) and was replicated in the validation cohort (n = 130, 25% of ischemic origin, c-statistic = 0.75). With a score ≥ 4, sensitivity was 85% (95% confidence interval = 68-95) and specificity was 52% (95% confidence interval = 41-62). In both cohorts, ophthalmologic evaluation found a vascular cause in 4% and was noncontributive in 85%. After 3 months, no patients had a stroke, TIA, or retinal infarct.

CONCLUSIONS

Our score may assist in predicting a vascular origin of TVD. Ophthalmologic evaluation, when not readily available, should not delay the neurovascular evaluation.

Safety and Efficacy of Selective Intra-arterial Thrombolysis for Central Retinal Artery Occlusion

PURPOSE

The purpose of this study was to determine the efficacy and safety of selective intra-arterial thrombolysis in patients with central retinal artery occlusion (CRAO).

METHODS

Medical records for 44 eyes of 44 patients diagnosed with acute non-arteritic CRAO and thrombolysis between October 2010 and February 2019 were analyzed retrospectively. Based on visual acuity, fundoscopic findings, and fluorescein angiography, the patients were classified into three stages: incomplete, subtotal, and total. The perfusion state using the best-corrected visual acuity (BCVA), arm to retina time, and arteriovenous passage times, after 1 month, 6 months, and at the final visit after the procedure, were compared with baseline readings.

RESULTS

Improvement of visual acuity was confirmed in 31 out of 44 patients (70.45%). The mean BCVA of 44 patients changed from 1.65 ± 0.78 logarithmic minimum angle of resolution (logMAR) at the first visit to 1.18 ± 0.91 logMAR at the last visit (p = 0.114). The BCVA according to CRAO stage was 0.08 ± 0.11 logMAR for the incomplete stage at the first visit, 0.06 ± 0.05 logMAR (p = 0.933) 1 month after the procedure, and 0.05 ± 0.07 logMAR (p = 0.933) at the last visit. In the subtotal stage, the results were 1.81 ± 0.54 logMAR at the first visit, 1.63 ± 0.76 logMAR (p = 0.035) 1 month after the procedure, and 1.36 ± 0.85 logMAR (p = 0.014) at the last visit. For the total stage of BCVA, the result at the first visit was 2.36 ± 0.25 logMAR, and it was 2.30 ± 0.30 logMAR (p = 0.510) 1 month after the procedure, and 2.42 ± 0.30 logMAR (p = 0.642) at the last visit. Reperfusion was observed in 40 patients out of the 44 (90.91%).

CONCLUSIONS

Selective intra-arterial thrombolysis can be helpful in patients with subtotal CRAO in terms of visual improvement and retinal arterial reperfusion.

Transient visual blurring during a sexual intercourse in a young woman with surgically corrected myopia and unrecognized pigmentary glaucoma: A rare case report

PURPOSE

To present a rare case of unilateral visual loss episodes occurred during sexual intercourse in a young patient affected by unrecognized pigmentary glaucoma and previously undergone myopic refractive surgery.

CASE DESCRIPTION

The patient presented surgically flattened corneas and markedly asymmetric pigmentary glaucoma.

CONCLUSIONS

Previous refractive surgery, sexual intercourse, and athletic lifestyle might be risk factors for acute pigment dispersion and chronic progression of pigmentary glaucoma in young myopic patients. During their ophthalmic examination prior to refractive surgery, greater attention should be paid to detect early signs of pigmentary dispersion, and awareness of these dangerous situations should be raised in affected patients.

Transient Monocular Visual Loss: When Is It an Emergency?

BACKGROUND

Patients who experienced transient monocular vision loss (TMVL) commonly present to the emergency department for evaluation. Although multiple etiologies can cause TMVL, it is most important to identify patients with retinal ischemia and those with vasculitis (giant cell arteritis) as the cause of TMVL. Patients with transient retinal ischemia have the same risk of cardiovascular events and death as patients who experienced transient brain ischemia. Patients with giant cell arteritis are at imminent risk of visual loss.

CASE REPORT

A 65-year-old man noticed three separate episodes of sudden onset of blurry vision in one eye. Ophthalmologic examination was normal but, as his symptoms were compatible with transient retinal ischemic attack, urgent investigations were initiated. He had normal inflammatory markers but computed tomography angiogram of the brain and neck demonstrated a large plaque in the ipsilateral internal carotid artery. Double anti-platelet therapy was started and stenting of the involved carotid artery was performed. The patient was symptom-free at the last follow-up. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Patients with retinal ischemia as the etiology of TMVL are at high risk of cardiovascular events and death. Their risk of cerebrovascular accidents is highest within 48 h from the episode of TMVL, thus they should have an urgent ophthalmologic examination and, if it is unrevealing, inflammatory markers should be checked and an urgent stroke prevention protocol should be initiated. Appropriate management with medical or surgical interventions significantly reduces morbidity and mortality in these patients.

MicroRNA-222-3p participates in the development of oral squamous cell carcinoma by targeting CDKN1B

OBJECTIVE

The aim of this study was to explore the potential role and regulatory mechanism of microRNA (miR)-222-3p in oral squamous cell carcinoma (OSCC).

METHODS

The expression level and prognostic significance of miR-222-3p was detected in OSCC tissues. CCK-8, transwell, and flow cytometry assays were used to explore the effect of miR-222-3p on cell proliferation, migration, invasion, and apoptosis. The influence of miR-222-3p on cyclin-dependent kinase inhibitor 1B (CDKN1B) expression was evaluated by luciferase assays, real-time polymerase chain reaction, and Western blot.

RESULTS

We found that miR-222-3p was overexpressed in OSCC tissues, comparing with normal tissues. Kaplan-Meier curves showed that OSCC patients with high expression of miR-222-3p (P = .003) showed worse overall survival than those patients with low expression of miR-222-3p. Multivariate analysis showed that miR-222-3p (P = .037) expression was an independent prognostic factor of OSCC patients. miR-222-3p promoted cell proliferation, migration and invasion and induced the apoptosis of SCC-15 and Tca-83 cells. Furthermore, luciferase reporter assays indicated that CDKN1B is targeted by miR-222-3p in OSCC cells. Overexpression of CDKN1B inhibited OSCC cell proliferation, migration, and invasion and promoted cell apoptosis rate.

CONCLUSIONS

miR-222-3p affects OSCC cell proliferation, migration, invasion, and apoptosis through targeting CDKN1B, and may be a potential prognostic biomarker for OSCC patients.

A case report of isolated orbital vasculitis mimicking retinal migraine: A potential cause of recurrent transient monocular blindness and ipsilateral headache

BACKGROUND

Retinal migraine is an important differential diagnosis of recurrent transient monocular blindness accompanied by headache when other etiologies are excluded. Here, we report a case of orbital vasculitis which initially mimicked retinal migraine.

CASE REPORT

A 47-year-old woman had recurrent episodes of fully reversible transient monocular blindness accompanied by ipsilateral headache for 15 months. The patient's neuroimaging and cardiac and ophthalmologic evaluations were normal. With a diagnosis of retinal migraine, her symptoms remitted in response to prophylactic treatment with topiramate and propranolol for 8 months. Three months after discontinuation of medications, transient monocular blindness recurred. High-resolution vessel wall magnetic resonance imaging revealed enhancement of the ipsilateral orbital vessels. Isolated orbital vasculitis was diagnosed. Complete remission of transient monocular blindness was achieved after steroid pulse therapy.

DISCUSSION

Isolated orbital vasculitis should be considered in differential diagnosis of recurrent transient monocular blindness and ipsilateral headache. High-resolution vessel wall magnetic resonance imaging can be helpful for the diagnosis.

Acute retinal arterial ischemia

Acute retinal arterial ischemia, which includes transient monocular vision loss (TMVL), branch retinal artery occlusion (BRAO), central retinal artery occlusion (CRAO) and ophthalmic artery occlusion (OAO), is most commonly the consequence of an embolic phenomenon from the ipsilateral carotid artery, heart or aortic arch, leading to partial or complete occlusion of the central retinal artery (CRA) or its branches. Acute retinal arterial ischemia is the ocular equivalent of acute cerebral ischemia and is an ophthalmic and medical emergency. Patients with acute retinal arterial ischemia are at a high risk of having further vascular events, such as subsequent strokes and myocardial infarctions (MIs). Therefore, prompt diagnosis and urgent referral to appropriate specialists and centers is necessary for further work-up (such as brain magnetic resonance imaging with diffusion weighted imaging, vascular imaging, and cardiac monitoring and imaging) and potential treatment of an urgent etiology (e.g., carotid dissection or critical carotid artery stenosis). Since there are no proven, effective treatments to improve visual outcome following permanent retinal arterial ischemia (central or branch retinal artery occlusion), treatment must focus on secondary prevention measures to decrease the likelihood of subsequent ischemic events.

Management of Acute Retinal Ischemia: Follow the Guidelines!

Acute retinal arterial ischemia, including vascular transient monocular vision loss (TMVL) and branch (BRAO) and central retinal arterial occlusions (CRAO), are ocular and systemic emergencies requiring immediate diagnosis and treatment. Guidelines recommend the combination of urgent brain magnetic resonance imaging with diffusion-weighted imaging, vascular imaging, and clinical assessment to identify TMVL, BRAO, and CRAO patients at highest risk for recurrent stroke, facilitating early preventive treatments to reduce the risk of subsequent stroke and cardiovascular events. Because the risk of stroke is maximum within the first few days after the onset of visual loss, prompt diagnosis and triage are mandatory. Eye care professionals must make a rapid and accurate diagnosis and recognize the need for timely expert intervention by immediately referring patients with acute retinal arterial ischemia to specialized stroke centers without attempting to perform any further testing themselves. The development of local networks prompting collaboration among optometrists, ophthalmologists, and stroke neurologists should facilitate such evaluations, whether in a rapid-access transient ischemic attack clinic, in an emergency department-observation unit, or with hospitalization, depending on local resources.

Transient monocular blindness: Vascular causes and differential diagnoses

Transient monocular blindness is an acute episode of ischemic origin in which one eye has profound visual loss, followed by full recovery within one hour. Transient monocular blindness most often occurs in the setting of retinal ischemia secondary to carotid embolism, but other mechanisms have been reported, including thrombosis (most often in the setting of giant cell arteritis), hemodynamic disorders (secondary to severe carotid stenosis), or vasospasm. Transient monocular blindness is considered a transient ischemic attack originating in the carotid arteries, and must be managed the same as transient ischemic attack involving the brain, in order to prevent a subsequent stroke.

Update on the Management of Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is caused by partial or complete occlusion of the central retinal artery, most commonly by an embolus from the ipsilateral carotid artery, aortic arch, or heart, and is the ocular equivalent of an acute cerebral ischemic event. The risk factors for a CRAO and acute cerebral ischemia are very similar, if not identical. Because no current therapeutic intervention has been shown to improve visual outcomes compared with the natural history of CRAO, management of CRAO should be focused on secondary prevention of vascular events, such as cerebral ischemia, myocardial infarction, and cardiovascular death.

Amaurosis fugax - delay between symptoms and surgery by specialty

Purpose

To describe the time course of management of patients with amaurosis fugax and analyze differences in management by different specialties.

Methods

Patients diagnosed with amaurosis fugax and subjected to carotid ultrasound in 2004–2010 at the Sahlgrenska University Hospital, Gothenburg, Sweden (n=302) were included in this retrospective cohort study, and data were collected from medical records.

Results

The prevalence of significant carotid stenosis was 18.9%, and 14.2% were subjected to carotid endarterectomy. A trend of longer delay for surgery was noted for patients first consulting a general practitioner (P=0.069) as compared to hospital-based specialties. For 46.3% of the patients, an ophthalmologist was their first medical contact. No significant difference in time interval to endarterectomy was seen between ophthalmologists and neurologists/internists. Only 31.8% of the patients with significant carotid stenosis had carotid endarterectomy within 2 weeks from the debut of symptoms, and this proportion was smaller for patients residing outside the Gothenburg city area (P=0.038).

Conclusion

Initially consulting an ophthalmologist does not delay the time to ultrasound or carotid endarterectomy. The overall time from symptoms to surgery is longer than recommended for a majority of the patients, especially for patients from rural areas and for patients initially consulting a general practitioner.

Amaurosis fugax: risk factors and prevalence of significant carotid stenosis

Purpose

The purpose of this study was to describe clinical characteristics and prevalence of carotid stenosis in patients with amaurosis fugax (AF).

Method

Patients diagnosed with AF and subjected to carotid ultrasound in 2004–2010 in Sahlgrenska University Hospital, Gothenburg (n=302), were included, and data were retrospectively collected from medical records.

Results

The prevalence of significant carotid stenosis was 18.9%, and 14.2% of the subjects were subjected to carotid endarterectomy. Significant associations with risk of having ≥70% stenosis were male sex (adjusted odds ratio [aOR]: 2.62; 95% confidence interval [CI]: 1.26–5.46), current smoking (aOR: 6.26; 95% CI: 2.62–14.93), diabetes (aOR: 3.68; 95% CI: 1.37–9.90) and previous vasculitis (aOR: 10.78; 95% CI: 1.36–85.5). A majority of the patients (81.4%) was seen by an ophthalmologist prior to the first ultrasound. Only 1.7% of the patients exhibited retinal artery emboli at examination.

Conclusion

The prevalence of carotid stenosis among patients with AF is higher than has previously been demonstrated in stroke patients. An association with previously reported vascular risk factors and with vasculitis is seen in this patient group. Ocular findings are scarce.

A fatal case of primary cardiac chondrosarcoma presenting with amaurosis fugax

A 64-year-old previously healthy woman consulted her general practitioner because of recurrent episodes of right-sided monocular transient visual loss (ie, amaurosis fugax). At first, these symptoms were followed over time, but as the attacks worsened, and were accompanied by dizziness and general discomfort, the patient was admitted to the department of neurology for further investigations. CT of the brain was normal; however, during admission, the patient developed rapid atrial fibrillation and was transferred to the department of cardiology. Transthoracic echocardiography revealed a massive tumour on the atrial side of the anterior mitral valve leaflet, partly obstructing the mitral valve inflow. The tumour was excised and a biological prosthetic mitral valve inserted. The tumour was histologically determined to be a highly malignant dedifferentiated chondrosarcoma. After 6 months, the tumour relapsed and expanded aggressively to completely obstruct the mitral valve inflow, ultimately leading to cardiac arrest and death.

Retinal and optic nerve ischemia

PURPOSE OF REVIEW

This review focuses on aspects of retinal and optic nerve ischemia that may be encountered by neurologists.

RECENT FINDINGS

Recent guidelines have emphasized the similarities between cerebral and retinal ischemia in terms of etiologic workup, acute management, and subsequent stroke risk. However, although ischemic optic neuropathies reflect optic nerve ischemia, they result from local small vessel disease and are not associated with a higher risk of cerebral infarction. Their management is therefore very different from acute cerebral ischemia. It is essential to rule out giant cell arteritis in all patients with acute retinal or optic nerve ischemia.

SUMMARY

Because the eye is vascularized by branches of the internal carotid artery, retinal ischemic symptoms are common in patients with anterior circulation ischemic strokes. Patients with central retinal artery occlusion, whether permanent or transient (responsible for transient visual loss), need to be evaluated and managed emergently similar to patients with cerebral ischemia, while anterior and posterior ischemic optic neuropathy are more concerning for giant cell arteritis.

Concurrent acute brain infarcts in patients with monocular visual loss

OBJECTIVE

Embolism from a proximal source to the retinal circulation could be a sign of embolism from the same source to the hemispheric circulation. We sought to determine the frequency of acute brain infarcts on diffusion-weighted imaging (DWI) in patients with monocular visual loss of presumed ischemic origin (MVL).

METHODS

We retrospectively studied 129 consecutive patients with MVL secondary to retinal ischemia. All patients underwent DWI, comprehensive ophthalmologic and neurologic examination, and diagnostic evaluations for the underlying etiology. Statistical analyses explored univariate and multivariate predictors of DWI evidence of acute brain infarcts.

RESULTS

DWI revealed concurrent acute brain infarct(s) in 31 of the 129 patients (24%). The probability of positive DWI was higher in embolic versus nonembolic MVL (28 vs 8%, p = 0.04), in MVL characterized by permanent visual loss versus transient symptoms (33 vs 18%, p = 0.04), and in MVL associated with concurrent hemispheric symptoms versus isolated MVL (53 vs 20%, p < 0.01). Patients with positive DWI were more likely to harbor a major underlying etiology as compared to those with normal DWI (odds ratio, 3.7; 95% confidence interval, 1.5-9.4).

INTERPRETATION

This study demonstrates that MVL does not always represent an isolated disease of the retina; approximately 1 of every 4 patients with MVL demonstrates acute brain infarcts on DWI. Because patients with concurrent brain infarcts are more likely to exhibit a cardiac or vascular source of embolism, imaging evidence of brain injury in patients with MVL may be a useful marker to guide the timing and extent of diagnostic examinations.

Vascular neuro-ophthalmology

Vascular neuro-ophthalmology includes visual symptoms and signs found in stroke patients as well as numerous primary vascular disorders involving the eye and the optic nerves. Cerebrovascular diseases are commonly associated with neuro-ophthalmologic symptoms or signs, which mostly depend on the type, size, and location of the vessels involved, and the mechanism of the vascular lesion. Funduscopic examination allows direct visualization of the retinal circulation, which shares many common characteristics with the cerebral microcirculation, and can be used as a marker of vascular disease.

Transient monocular visual loss

Transient monocular visual loss is an important clinical complaint and has a number of causes, of which the most common is retinal ischemia. A practical approach is to perform a careful examination to determine whether there are any eye abnormalities that can explain the visual loss. Despite the transient nature of the symptom, there may be clues to the diagnosis on the examination even after the visual loss has recovered.

Intra-arterial thrombolysis for central retinal artery occlusion: two cases report

Central retinal artery occlusion (CRAO) causes severe visual loss in affected eye and vision does not recover in more than 90% of the patients. It is believed that it occurs by occlusion of the central retinal artery with small emboli from atherosclerotic plaque of internal cerebral artery. Retina is a part of the brain, thus basically CRAO is corresponding to acute occlusion of intracerebral artery and retinal ischemia is to cerebral stroke. Therefore, intra-arterial thrombolysis (IAT) has been considered as a treatment method in CRAO. Recently, we treated 2 patients diagnosed as CRAO and could achieve complete recanalization on fundus fluorescein angiogram with IAT. Of them, one recovered visual acuity to 20/25. We report our 2 CRAO cases treated with IAT and discuss technical aspects for IAT and management of patient. To the best of our knowledge, this is the first Korean report of IAT for CRAO.

[Vascular transient monocular visual loss]

Diagnosis and management of transient monocular visual loss is an emergency. Ocular conditions causing transient visual loss are routinely managed by ophthalmologists. Vascular transient monocular visual loss may result from emboli, hypoperfusion, vasospasm, or venous congestion. Evaluation focuses on the carotid arteries, ophthalmic arteries, the aortic arch, the heart, and rarely hypercoagulable states. Secondary prevention of ischemic events is essential in order to prevent permanent visual loss as well as cerebral ischemic and cardiovascular death. Aggressive treatment of vascular risk factors is usually associated with antiplatelet agents. Anticoagulant and carotid surgery are only rarely required after vascular transient monocular visual loss.

[Transient visual loss: a practical approach]

Transient vision loss results from a variety of disorders including benign dry eye as well as vision- or life-threatening disorders such as giant cell arteritis. The goal of the initial evaluation is to determine the most likely mechanism based on the past medical history, characteristics of visual loss, and ophthalmologic and neurologic examinations. The ophthalmologist is often the first physician consulted and plays an essential role. Indeed, identification of the mechanism of transient visual loss allows the care-taker to properly decide on the work-up, its timing (emergency or otherwise), and subsequent treatment.

Thrombolytic therapy in central retinal artery occlusion: cutting edge therapy, standard of care therapy, or impractical therapy?

PURPOSE OF REVIEW

Numerous therapeutic options have been suggested for the treatment of central retinal artery occlusion (CRAO) such as ocular massage, anterior chamber paracentesis, physical exercise, and medication-induced reduction of intraocular pressure. Because of the lack of a proven effective treatment for CRAO, there has been a strong effort to develop alternative therapies. Recently, thrombolytic therapy has been suggested as a viable therapy for CRAO. The aim of this review is to provide an update on the progress of thrombolytic therapy for CRAO.

RECENT FINDINGS

Although there is no consensus on a standardized treatment regimen for CRAO, emerging evidence suggests that thrombolytic therapy may be effective if administered promptly. Despite the benefit of thrombolytic therapy, on the basis of the results of case reports and case series, randomized controlled studies are necessary to ultimately prove the effectiveness of the treatment.

SUMMARY

Thrombolytic therapy has yet to be validated as an effective treatment of CRAO. The execution of randomized, controlled trials is greatly needed to establish whether thrombolytic therapy can be considered standard of care therapy for CRAO.

Migraine headaches: diagnosis and management

BACKGROUND

Patients often complain to their optometrist about their headaches, of which migraines are a common type. They may ask if their pain is from visual causes or whether the visual auras they experience are normal.

METHODS

The literature on migraine is reviewed to provide the optometrist with current information to manage these patients.

RESULTS

Included in the review are migraine epidemiology, pathophysiology, categorization, clinical presentation, diagnosis, and treatment.

CONCLUSION

Optometrists can help their migraine patients with a thorough examination, advice, proper referrals, and optical management when appropriate.

Intravenous thrombolysis with low-dose recombinant tissue plasminogen activator in central retinal artery occlusion

PURPOSE

To evaluate the beneficial effect of intravenous thrombolysis aiming at rapid restoration of blood flow during the early hours of a central retinal artery occlusion (CRAO).

DESIGN

Interventional case series.

METHODS

In the present study, we prospectively evaluated the visual outcome after thrombolytic treatment with low-dose (50 mg) rt-PA (recombinant tissue plasminogen activator) and concomitant intravenous heparinization in patients with acute CRAO, best-corrected visual acuity (BCVA) < or = 20/100, and onset of symptoms within 12 hours prior to treatment.

RESULTS

Twenty-eight patients (28 eyes) were included in this study. Final visual acuity was improved three or more lines in nine eyes (32%), stable in 18 (64%), and worse in one eye. Time to treatment < or = 6.5 hours was associated with a better gain of lines of vision (P = .004). Seven of 17 eyes (41%) that received thrombolytic treatment within the first 6.5 hours achieved a final BCVA > or = 20/50, compared to none in the subgroup of patients with onset to treatment >6.5 hours (P = .023). We observed no serious adverse events.

CONCLUSIONS

Our findings indicate that thrombolytic treatment with intravenous low-dose rt-PA is of value for an improved visual recovery in patients with acute CRAO, if administered within the first 6.5 hours after the onset of symptoms.

Transient monocular vision loss from acute rheumatic fever

A 15-year-old male developed transient monocular visual loss secondary to retinal artery flow disturbance, vasospasm, and possible microemboli associated with acute rheumatic heart disease. He had insufficiently treated streptococcal pharyngitis. Inadequately treated rheumatic carditis should be considered among the causes of transient monocular visual loss in children.

Label-free calcium imaging in ischemic retinal tissue by TOF-SIMS

The distribution and movement of elemental ions in biologic tissues is critical for many cellular processes. In contrast to chemical techniques for imaging the intracellular distribution of ions, however, techniques for imaging the distribution of ions across tissues are not well developed. We used time-of-flight secondary ion mass spectrometry (TOF-SIMS) to obtain nonlabeled high-resolution analytic images of ion distribution in ischemic retinal tissues. Marked changes in Ca(2+) distribution, compared with other fundamental ions, such as Na(+), K(+), and Mg(2+), were detected during the progression of ischemia. Furthermore, the Ca(2+) redistribution pattern correlated closely with TUNEL-positive (positive for terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labeling) cell death in ischemic retinas. After treatment with a calcium chelator, Ca(2+) ion redistribution was delayed, resulting in a decrease in TUNEL-positive cells. These results indicate that ischemia-induced Ca(2+) redistribution within retinal tissues is associated with the order of apoptotic cell death, which possibly explains the different susceptibility of various types of retinal cells to ischemia. Thus, the TOF-SIMS technique provides a tool for the study of intercellular communication by Ca(2+) ion movement.

Thrombolysis for Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) frequently causes severe and irreversible visual loss. For many years, various conservative treatments have been proposed for acute CRAO, but their efficacy remains unproven. Over the past 20 years, CRAO has also been treated with thrombolytic agents administered intravenously or intra-arterially. However, all thrombolytic studies are retrospective and uncontrolled, so that the benefit of this treatment remains uncertain. A prospective controlled clinical trial is ongoing in Europe and should provide more reliable information. Even if this trial demonstrates a benefit, thrombolytic treatment is unlikely to become widespread in the management of CRAO unless it can be deployed quickly after the event.