Amaurosis fugax in young people

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.

Using optical coherence tomography and optical coherence tomography angiography to delineate neurovascular homeostasis in migraine: a review

Migraine is one of the world's most debilitating disorders, and it has recently been shown that changes in the retina can be a potential biomarker for the disease. These changes can be detected by optical coherence tomography (OCT), which measures retinal thickness, and optical coherence tomography angiography (OCTA), which measures vessel density. We searched the databases Google Scholar, ProQuest, Scopus, and Web of Science for studies in English using OCT and OCTA in migraineurs, using the search terms "optical coherence tomography," "OCT," "optical coherence tomography angiography," "OCTA" and "migraine." We found 73 primary studies, 11 reviews, and 8 meta-analyses pertaining to OCT and OCTA findings in migraineurs. They showed that migraineurs had reduced retinal thickness (via OCT), retinal vessel density, and greater foveal avascular zone area (via OCTA) than controls. OCTA changes reflect a perfusion compromise occurring in migraineurs as opposed to in healthy controls. OCT and OCTA deficits were worse in migraine-with-aura and chronic migraine than in migraine-without-aura and episodic migraine. Certain areas of the eye, such as the fovea, may be more vulnerable to these perfusion changes than other parts. Direct comparison between study findings is difficult because of the heterogeneity between the studies in terms of both methodology and analysis. Moreover, as almost all case-control studies were cross-sectional, more longitudinal cohort studies are needed to determine cause and effect between migraine pathophysiology and OCT/OCTA findings. Current evidence suggests both OCT and OCTA may serve as retinal markers for migraineurs, and further research in this field will hopefully enable us to better understand the vascular changes associated with migraine, perhaps also providing a new diagnostic and therapeutic biomarker.

Transient Visual Loss in Young Females with Crowded Optic Discs: A Proposed Aetiology

I present four cases of transient visual loss (TVL) in young females with crowded optic discs. One patient had asymmetrical cup-to-disc ratios and only experienced TVL in the eye with the more crowded disc. I review the evidence for blood flow autoregulatory dysfunction within crowded optic discs in combination with reduced ocular perfusion pressure to propose a possible aetiology for both unilateral and bilateral TVL in young females with crowded optic discs.

Homocysteinemia as a cause for amaurosis fugax in a patient without an apparent embolic source

Purpose: To report a case with monocular transient vision loss (TVL) associated with Hyperhomocysteinemia. Methods: We present a case with persistent TVL attacks and high level of homocysteine. Results: A 32-year-old male had a history of episodes of recurrent monocular TVL. Extensive ophthalmic, systemic and laboratory studies were unremarkable with the exception of high plasma homocysteine level. He never experienced TVL during the 36-month follow-up after starting folate, B12 and B6 except for one episode in which he had discontinued the treatment for three months. Conclusion: This case may suggest hyperhomocysteinemia as one of the underlying causes of recurrent attacks of TVL without any known source of emboli.

Optical Coherence Tomography in Patients with Chronic Migraine: Literature Review and Update

Migraine is a chronic disease characterized by unilateral, pulsating, and often moderate-to-severe recurrent episodes of headache with nausea and vomiting. It affects approximately 15% of the general population, yet the underlying pathophysiological mechanisms are not fully understood. Optical coherence tomography (OCT) is a safe and reproducible diagnostic technique that utilizes infrared wavelengths and has a sensitivity of 8–10 μm. It can be used to measure thinning of the retinal nerve fiber layer (RNFL) in some neurological disorders. Although ophthalmologists are often the first specialists to examine patients with migraine, few studies have addressed the involvement of the optic nerve and retino-choroidal structures in this group. We reviewed the literature on the etiological and pathological mechanisms of migraine and the relationship between recurrent constriction of cerebral and retrobulbar vessels and ischemic damage to the optic nerve, retina, and choroid. We also assessed the role of OCT for measuring peripapillary RNFL thickness and macular and choroidal changes in migraine patients. There is considerable evidence of cerebral and retrobulbar vascular involvement in the etiology of migraine. Transitory and recurrent constriction of the retinal and ciliary arteries may cause ischemic damage to the optic nerve, retina, and choroid in patients with migraine. OCT to assess the thickness of the peripapillary RNFL, macula, and choroid might increase our understanding of the pathophysiology of migraine and facilitate diagnosis of retino-choroidal compromise and follow-up of therapy in migraine patients. Future studies should determine the usefulness of OCT findings as a biomarker of migraine.

Ocular pulse amplitude and retina nerve fiber layer thickness in migraine patients without aura

Background

To evaluate the ocular pulse amplitude (OPA), the posterior pole asymmetry analysis (PPAA), the peripapillary retinal nerve fiber layer (RNFL) thickness, the ganglion cell layer (GCL) thickness, macular thickness and visual field testing in migraine patients without aura.

Methods

In this prospective, cross-sectional and comparative study 38 migraine patients and 44 age and sex matched controls were included. OPA was measured by dynamic contour tonometry (DCT), PPAA, RNFL, GCL and macular thickness were measured by Heidelberg Spectral Domain Optical Coherence Tomography (SD-OCT) and standard perimetry was performed using the Humphrey automated field analyzer.

Results

The difference in OPA was not statistically significant between the two groups (p ≥ 0.05). In the PPAA there was no significant difference between two hemispheres in each eye (p ≥ 0.05). The RNFL thickness was significantly reduced in the temporal and nasal superior sectors in the migraine group (p ≤ 0.05). The GCL and macular thickness measurements were thinner in migraine patients but the difference between groups was not statistically significant (p ≥ 0.05). There was no correlation between RNFL, GCL, macular thickness measurements and OPA values. There was no significant difference in the mean deviation (MD) and pattern standard deviation (PSD) between the two groups (p ≥ 0.05).

Conclusions

Migraine patients without aura have normal OPA values, no significant asymmetry of the posterior pole and decreased peripapillary RNFL thickness in the temporal and nasal superior sectors compared with controls. These findings suggest that there is sectorial RNFL thinning in migraine patients without aura and pulsative choroidal blood flow may not be affected during the chronic course of disease.

Patterns of non-embolic transient monocular visual field loss

The aim of this study was to systematically describe the semiology of non-embolic transient monocular visual field loss (neTMVL). We conducted a retrospective case note analysis of patients from Moorfields Eye Hospital (1995-2007). The variables analysed were age, age of onset, gender, past medical history or family history of migraine, eye affected, onset, duration and offset, perception (pattern, positive and negative symptoms), associated headache and autonomic symptoms, attack frequency, and treatment response to nifedipine. We identified 77 patients (28 male and 49 female). Mean age of onset was 37 years (range 14-77 years). The neTMVL was limited to the right eye in 36 % to the left in 47 % and occurred independently in either eye in 5 % of cases. A past medical history of migraine was present in 12 % and a family history in 8 %. Headache followed neTMVL in 14 % and was associated with autonomic features in 3 %. The neTMB was perceived as grey in 35 %, white in 21 %, black in 16 % and as phosphenes in 9 %. Most frequently neTMVL was patchy 20 %. Recovery of vision frequently resembled attack onset in reverse. In 3 patients without associated headache the loss of vision was permanent. Treatment with nifedipine was initiated in 13 patients with an attack frequency of more than one per week and reduced the attack frequency in all. In conclusion, this large series of patients with neTMVL permits classification into five types of reversible visual field loss (grey, white, black, phosphenes, patchy). Treatment response to nifidipine suggests some attacks to be caused by vasospasm.

Retinal, ophthalmic, or ocular migraine

Ocular migraine, an uncommon cause of transient monocular visual loss, is an entity physicians should be able to recognize in order to provide appropriate treatment and to avoid unnecessary testing. The following text provides an overview of ocular migraine, including discussion of accepted terminology, clinical presentation, and pathophysiology. An ocular and systemic differential diagnosis, appropriate evaluation, therapy, and prognosis are also discussed.

Acute macular neuroretinopathy: a review of the literature

Acute macular neuroretinopathy (AMNR) is a rare condition that produces transient or permanent visual impairment. Typical cases have acute onset multifocal scotomas that correspond rather precisely with reddish, flat, or depressed circumscribed lesions in the macula. These lesions are wedge-shaped and generally point toward the fovea. The pathophysiology of AMNR is unclear, the causes are uncertain, and there is no specific treatment for this condition. This review summarizes the presentation, possible risk factors, and prognosis of the 41 cases of AMNR reported in the published, English-language literature from 1975 through April 2002. Possible areas for future research into the etiology of this rare condition are discussed.

Perspectives on migraine: prevalence and visual symptoms

About 20 per cent of women and 10 per cent of men experience migraine at some time in their lives, of whom about one half to two thirds will have had a migraine attack in the previous 12 months. Prevalences of this order have been found in a survey of patients in an Australian optometric practice. Between one third and one half of migraineurs experience sensory or motor aura. Visual aura are by far the most common of the aura. A high proportion (more than 40 per cent) of migraineurs presenting for routine optometric examination will not have had their headache or aura formally diagnosed. Optometrists can give reassurance by providing a formal diagnosis and, when appropriate, they can refer their migraine patients to sources of advice on how the frequency and severity of their attacks might be ameliorated. The diagnosis of migraine is straightforward when the migrainous episode and any associated aura follow a classical pattern. However, diagnosis is often challenging, especially for aura occurring without headache, when the aura are atypical, when the first attack of migraine occurs after the age of 50 years, when there are persistent visual field losses or when there are pupillary anomalies or extra-ocular muscle palsy and diplopia associated with the migraine. Unusual presentations must be approached with care, using a good knowledge of the diversity of migraine, careful history taking and a thorough ocular and visual examination. As visual field losses can be associated with migraine and migraine may be a risk factor for low-tension glaucoma, visual field examination is often indicated for patients with a history of migraine. In some cases of migraine, referral for neurological work-up will be necessary before concluding that the headache and visual symptoms can be attributed to migraine.

The prevalence and symptoms of migraine in a consecutive series of patients attending an optometric practice

The purpose of the investigation was to determine the prevalence of migraine in optometric practice and to document the variety of presentation. One thousand consecutively presenting patients of a suburban optometric practice were asked questions to establish whether they experience migraine or have experienced it in the past. Those with a history of migraine were asked further questions to establish the type of migraine and to document the variety of the symptoms they experienced. Eleven percent of male and 23% of female patients currently had migraine or had experienced it in the past. When corrected for the age distribution of the population of the state from which the sample was drawn, it is estimated that the general population prevalence of migraine is 9.5% for men and 19.7% for women. Half of the sample of migraineurs had not experienced a migraine within the last 12 months. A third had a known family history of migraine. Nearly half had not had a formal medical diagnosis of their migraine but only 7 had attended for optometric examination because of their migraine symptoms. Four of these patients had single migraine-like episodes and three had migraine equivalents (acephalic migraine, experiencing the visual aura without headache). Optometrists must be thoroughly familiar with migraine and its varied presentation because of its high prevalence, the explanatory value in offering a formal diagnosis of migraine, and the risk that headache or visual aura may be wrongly ascribed to migraine when there is some more sinister cause of the symptoms.

Amaurosis fugax in the young

A 36-year-old healthy woman developed amaurosis fugax of the right eye lasting 1 minute. Work-up revealed right carotid stenosis thought most compatible with an atherosclerotic plaque. A carotid endarterectomy was performed which corroborated the radiologic diagnosis. An embolic event from ipsilateral carotid artery disease should be considered as a cause of amaurosis fugax even in the young.

Benign episodic unilateral mydriasis. Clinical characteristics

PURPOSE

To describe the clinical features of the syndrome of neurologically isolated episodic unilateral mydriasis.

METHODS

Information was obtained by reviewing the case records of 24 patients evaluated by the author and collected by polling other neuro-ophthalmologists.

RESULTS

Nineteen patients were women. The median age was 31 years. Fourteen patients had migraines. The median interval between onset of events and evaluation was 6 months. The median duration and frequency of events were 12 hours and two to three per month, respectively. Most patients did not identify any factor that could precipitate an occurrence. The most common associated symptoms during an episode included visual blur in 15 patients, headache in 9, and orbital pain in 5. Eleven patients were examined during an attack. Three patients who were examined had impaired near vision, four had impaired accommodative function, and six had an anisocoria that increased with added ambient light. None of these patients had a tonic pupil or cholinergic agonist-induced pharmacologic mydriasis. Five other patients examined during an attack had normal vision and unimpaired direct light reactivity of their large pupil. No neurologic disorder was identified after neurodiagnostic testing, clinical evaluation, and natural history observation.

CONCLUSIONS

The syndrome of idiopathic episodic unilateral mydriasis probably comprises a heterogeneous group of conditions that result in parasympathetic insufficiency of the iris sphincter in some patients, and sympathetic hyperactivity of the iris dilator in others. Patients with episodes similar in characteristics to the ones described in this survey appear to have a benign neurologic prognosis, and do not require further neurodiagnostic studies.

Ocular migraine in an eight-year-old girl

BACKGROUND

A case of ocular migraine in an eight-year-old girl is presented. This is believed to be the youngest reported patient with ocular migraine.

CONCLUSION

The choroid was noted to darken during an episode of visual loss, suggesting choroidal ischaemia as the cause of the visual loss.

The source of embolism in amaurosis fugax and retinal artery occlusion

To assess the diagnostic value of an extensive cardiac screening and of carotid artery duplex scanning in patients suspected of suffering from retinal embolism, we examined 41 consecutive patients (mean age 59.6 years, range 36-74) who presented either with amaurosis fugax or with a retinal artery occlusion. In spite of extensive investigations, we found no cause in 27 patients (66%). In 11 patients (27%), symptoms were likely to be due to a stenosis or an occlusion of the ipsilateral carotid artery. In only 1 patient (2%), the heart was likely to be a source of embolism. We conclude that in patients in this age group suffering from either amaurosis fugax or a retinal artery occlusion, a carotid artery duplex scanning should be performed first as this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring and precordial echocardiography).