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Example of visual snow. Patients with visual snow observe tiny dots in the entire visual field. The dots often resemble the "static" from a detuned analogue television because the dots "flicker on and off". Classically, the dots are black/gray on a white background and white on a black background, but colors may vary.

Example of visual snow. Patients with visual snow observe tiny dots in the entire visual field. The dots often resemble the "static" from a detuned analogue television because the dots "flicker on and off". Classically, the dots are black/gray on a white background and white on a black background, but colors may vary.

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Migraine is a common headache disorder characterized by often-severe headaches that may be preceded or accompanied by a variety of visual symptoms. Although a typical migraine aura is not difficult to diagnose, patients with migraine may report several other visual symptoms, such as prolonged or otherwise atypical auras, “visual blurring”, “retinal...

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... snow is characterized by the continuous presence of countless small dots in the entire visual field (Figure 3) 50 . Patients often describe it as "TV static from a detuned analogue television" since the dots are flickering on and off 50 . ...

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... Aside from continuous VS for longer than 3 months, a diagnosis of VSS requires at least two additional visual symptoms of palinopsia (inability to suppress the just-seen), enhanced entoptic phenomena (inability to suppress the visualization of the optic apparatus), nyctalopia or photophobia. VSS is an independent entity from migraine and aura, yet approximately 60% of patients with VSS also experience concomitant migraine [4][5][6]. The disorder is rare, mostly occurring in young adulthood with mean age of onset in the third decade [1], yet a recent community-based study reported prevalence up to 2% [7]. ...
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Purpose: Visual snow syndrome (VSS) is a recently recognized chronic neurologic condition characterized by the constant perceiving of tiny flickering dots throughout the entire visual field. Metabolic overactivity and grey matter volume increase in the lingual gyrus has been reported. We investigated this by 18F-FDG PET/MR in comparison to healthy controls. Aside from voxel-based characterization, the classification accuracy of volume-of-interest (VOI)-based multimodal assessment was evaluated, also in comparison with visual analysis. Methods: Simultaneous 18F-FDG PET and MR imaging was performed in 7 patients with VSS (24.6 ± 5.7 years; 5 M/2F) and 15 age-matched healthy controls (CON) (28.0 ± 5.3 years; 8 M/7F). SPM12 and voxel-based morphometric analysis was performed. A VOI-based discriminant analysis was performed with relative 18F-FDG uptake, MR grey matter (GM) volumes and their combination. A visual analysis was done by two blinded experienced readers. Results: Relative increased hypermetabolism was found in VSS patients in the lingual gyrus and cuneus (pFWE < 0.05, peak change + 24%), and hypometabolism in the mesiotemporal cortex (pheight,uncorr < 0.001, peak change - 14%). VSS patients also had increased GM volume in the limbic system and frontotemporal cortex bilaterally (pFWE < 0.05), and in the left secondary and associative visual cortex and in the left lingual gyrus (pheight,uncorr < 0.001). Discriminant analysis resulted in 100% correct classification accuracy for 18F-FDG with lingual gyrus, cuneus and lateral occipital lobe (BA 17 and BA 18) as main discriminators. Unimodal MR- and combined 18F-FDG + MR classification resulted in an accuracy of 91% and 95%, respectively. Visual analysis of 18F-FDG was highly observer dependent. Conclusion: Patients with VSS have highly significant structural and metabolic abnormalities in the visual and limbic system. VOI-based discriminant analysis of 18F-FDG PET allows reliable individual classification versus controls, whereas visual analysis of experienced observers was highly variable. Further investigation in larger series, also in comparison to VSS mimicking disorders such as migraine, is warranted. Trail registration: Retrospectively registered at clinicaltrials.gov under NCT05569733 on Oct 5, 2022.
... Aside from continuous VS for longer than three months, a diagnosis of VSS requires at least two additional visual symptoms of palinopsia (inability to suppress the just-seen), enhanced entoptic phenomena (inability to suppress the visualization of the optic apparatus), nyctalopia or photophobia. VSS is an independent entity from migraine and aura, yet approximately 60% of patients with VSS also experience concomitant migraine [4][5][6]. The disorder is rare, mostly occurring in young adulthood with mean age of onset in the third decade [1], yet a recent community-based study reported prevalence up to 2% [7]. ...
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Purpose Visual snow syndrome (VSS) is a recently recognized chronic neurologic condition characterized by the constant perceiving of tiny flickering dots throughout the entire visual field. Metabolic overactivity and grey matter volume increase in the lingual gyrus has been reported. We investigated this by ¹⁸F-FDG PET/MR in comparison to healthy controls. Aside from voxel-based characterization, the classification accuracy of volume-of-interest (VOI) based multimodal assessment was evaluated, also in comparison with visual analysis. Methods Simultaneous ¹⁸F-FDG PET and MR imaging was performed in 7 patients with VSS (24.6 ± 5.7 yrs; 5M/2F) and 15 age-matched healthy controls (CON) (28.0 ± 5.3 yrs; 8M/7F). SPM12 and voxel-based morphometric (VBM) analysis was performed. A VOI-based discriminant analysis was performed with relative ¹⁸F-FDG uptake, MR grey matter (GM) volumes and their combination. A visual analysis was done by two blinded experienced readers. Results Relative increased hypermetabolism was found in VSS patients in the lingual gyrus and cuneus (pFWE<0.05, peak change + 24%), and hypometabolism in the mesiotemporal cortex (pheight,uncorr<0.001, peak change − 14%). VSS patients also had increased GM volume in the limbic system and frontotemporal cortex bilaterally (pFWE<0.05), and in the left secondary and associative visual cortex and in the left lingual gyrus (pheight,uncorr <0.001). Discriminant analysis resulted in 100% correct classification accuracy for ¹⁸F-FDG with lingual gyrus, cuneus and lateral occipital lobe (BA 17 and BA 18) as main discriminators. Unimodal MR- and combined ¹⁸F-FDG + MR classification resulted in an accuracy of 91% and 95%, respectively. Visual analysis of ¹⁸F-FDG was highly observer dependent. Conclusion Patients with VSS have highly significant structural and metabolic abnormalities in the visual and limbic system. VOI-based discriminant analysis of ¹⁸F-FDG PET allows reliable individual classification versus controls, whereas visual analysis of experienced observers was highly variable. Further investigation in larger series, also in comparison to VSS mimicking disorders such as migraine, is warranted. Retrospectively registered at clinicaltrials.gov under NCT05569733 on Oct 5, 2022.
... As a recurrent neurological disorder, ocular migraines usually manifest as attacks of temporary reversible neurological symptoms lasting between five and 20 minutes. There is a mix of positive and negative symptoms of auras, including visual, sensory, and linguistic manifestations [3]. It has been reported that ischemic optic neuropathy and permanent arcuate scotomas may occur as a result of cerebral and ocular migraine [4]. ...
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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.
... It was suggested in the mid-1990s that visual snow syndrome is a variant of migraine [25]. While many of the migraine features overlap with visual snow syndrome [26], visual phenomena are not directly linked to migrainous events, and the description of visual snow is clearly distinct from the typical content of migraine auras [25,27]. There is, however, one series of 3 patients reporting episodic visual snow, co-occurring with migraine [28]. ...
Article
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Purpose of Review Until the last 5 years, there was very little in the literature about the phenomenon now known as visual snow syndrome. This review will examine the current thinking on the pathology of visual snow and how that thinking has evolved. Recent Findings While migraine is a common comorbidity to visual snow syndrome, evidence points to these conditions being distinct clinical entities, with some overlapping pathophysiological processes. There is increasing structural and functional evidence that visual snow syndrome is due to a widespread cortical dysfunction. Cortical hyperexcitability coupled with changes in thalamocortical pathways and higher-level salience network controls have all shown differences in patients with visual snow syndrome compared to controls. Summary Further work is needed to clarify the exact mechanisms of visual snow syndrome. Until that time, treatment options will remain limited. Clinicians having a clearer understanding of the basis for visual snow syndrome can appropriately discuss the diagnosis with their patients and steer them towards appropriate management options.
... The life-time prevalence of migraine in the general population is 13% for men and 33% for women [14]. Migraine-like visual auras are attributed to neuronal hyper excitability that in its turn triggers cortical spreading depression [15]. ...
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Background To present a case with Ebstein anomaly, a rare congenital heart disorder, with ophthalmological and neurophthalmological signs and symptoms. To date, retinal venous dilatation and visual snow syndrome have not been previously been published in this anomaly. Case presentation A 10-year-old white girl was diagnosed with Ebstein anomaly. From age 12, she regularly suffered from migraines with auras and photophobia. At age 16 she started to see short-term bouts of white snow, that after a year were present all day. At age 20, she was found to have a decreased retinal arteriovenous ratio. Conclusions Retinal arterial tortuosity and venular dilatation are common in congenital heart disease but have not been described in Ebstein anomaly, nor has the visual snow syndrome.
... About onethird of migraine patients experience a visual manifestation of the disease in the form of a migraine aura. Migraine auras are reversible visual disturbances that can last from 5 to 60 min and that precede the headache attack [43]. ...
Article
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Optical coherence tomography angiography (OCT-A) was commercially introduced in 2014. OCT-A allows a fast, non-invasive, three-dimensional analysis of the retinal vasculature from the vitreoretinal interface to the choriocapillaris. The results can be evaluated separately in automated or custom-defined retinal layers. Since its introduction, OCT-A has also been used in patients with neurological diseases in order to find and characterize retinal biomarkers. Many neurological diseases have retinal manifestations, often preceding the key symptoms of the neurological disease. Anatomically and developmentally, the retina is a part of the brain. In contrast to the brain, the retina is easily accessible for imaging methods; moreover, retinal imaging is more cost-effective than brain imaging. In this review, the current knowledge about OCT-A findings and possible OCT-A biomarkers in neurological diseases is summarized and discussed regarding the value of OCT-A as a diagnostic tool in neurological diseases.
... 18 Migraine with Visual Aura VS was believed to be part of visual aura, which Schankin et al opposed. 1 The distinction of VSS from migraine with aura mainly depends on clinical features. VSS affects the whole visual field, shows no evidence of cortical spreading depression-like mechanism, 19 lacks classic migraine features like fortification spectra and scotomas, 20 and cannot be treated effectively with antimigraine drugs. 8 However, there is no denying that migraine is still a prevalent comorbidity of VSS. ...
Article
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Visual snow syndrome (VSS) is a clinical disorder characterized by pan-field visual disturbance. It is a diagnosis of exclusion since its pathophysiology remains unknown. Excluding other mimics is of great significance since some serious pathologies can have secondary visual snow (VS) as an initial presentation. Delayed or incorrect diagnosis of these VSS mimics may lead to permanent vision loss or even death. The purpose of this review is to help physicians distinguish VSS mimics promptly to avoid bad outcomes. The authors performed a PubMed literature search of articles, case reports, and reviews describing VS symptoms in patients with underlying diseases other than VSS. The red flags of secondary VS symptoms were highlighted, such as new-onset or intermittent VS, unilateral or quadrant VS, and accompanied ocular or neurological deficits. There are four main categories of VSS mimics, ie, including neurological disorders, ocular pathologies, drug-related VS, and other systemic diseases. The physicians could largely exclude most etiologies based on history taking, ophthalmologic and neurologic examinations, and neuroimaging. Further research in VS should carefully define and unify the inclusion and exclusion criteria of this disorder and investigate these secondary VS conditions and their pathogenesis.
... Apart from shorter duration (1-2 min), round and multicolored image perceptions have traditionally supported the diagnosis of visual partial epileptic seizures, contrary to angular, zig-zagged, frequently black-and-white longer perceptions, supposedly more frequent in migraine VA [29]. Colorful aura perceptions included rather small than large dots, lines, or the fortification spectrum [30,31]. In a retrospective study of VA in 122 patients with migraine, the patterns were described as black-and-white, blackand-silver, always colorful, both colorful and black-and-white, and without color in 30.3%, 20.5%, 18.0%, 22.2%, and 9.0%, respectively [20]. ...
... VA does not depend on visual input, as it can remain with one or both eyes closed [31]. Visual auras can also be seen with eyes opened in complete darkness. ...
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Migraine, the most frequent neurological ailment, affects visual processing during and between attacks. Most visual disturbances associated with migraine can be explained by increased neural hyperexcitability, as suggested by clinical, physiological and neuroimaging evidence. Here, we review how simple (e.g., patterns, color) visual functions can be affected in patients with migraine, describe the different complex manifestations of the so-called Alice in Wonderland Syndrome, and discuss how visual stimuli can trigger migraine attacks. We also reinforce the importance of a thorough, proactive examination of visual function in people with migraine.
... Migraine is a common headache disorder characterized by often-severe headaches that may be preceded or accompanied by a variety of visual symptoms. Although a typical migraine aura is not difficult to diagnose, patients with migraine may report several other visual symptoms, such as prolonged or otherwise atypical auras, "visual blurring", "retinal migraine", "ophthalmoplegic migraine", photophobia, palinopsia, and "visual snow" [14][15]. ...
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Abstract Sixteen patients ranging from 19 to 68 years-old were studied with Chronic Heredofamilial Migraine with Aura. The following symptoms were associated to chronic heredofamilial migraine: dizziness, vertigo, syncope, redness eye, photophobia, blurred vision and reduced and loss of vision, scintillant scotomas, dizziness, ears noise, temporospatial disorientation, memory disorders, effort dyspnea, asthenia, son phobia, nausea, vomits, and social, labor and home stress. The followings symptoms were interpreted as migraine auras: Blurred vision and reduced and loss of vision, scintillant scotomas, dizziness, ears noise. The following comorbidities were found: syncope, bradycardia, mitral prolapse and tachycardia, effort dyspnea, asthenia, seizures, environment, labor and home stress, sleep disorders or insomnia and constipation. The followings aspects were discussed: migraine and prodroms, migraine and vascular diseases, migrainous vertigo and dizziness, symptoms related to the visual system in migraine, migraine and sleep disorders, hemiplegic migraine, neural correlates of migraine, histamine and migraine, the calcitonin gene-related peptide in migraine and its role in migraine physiopathology, and migraine genetic.
... The visual symptoms gradually disappear with complete resolution and the migraine usually starts simultaneously with the resolution of the scotoma. In few cases, the aura is not followed by headache, this usually happening in elderly patients [2]. ...
Article
This paper aimed to present a relatively frequent misinterpretation of a migraine with visual aura. Sometimes, patients with aura and migraine are referred to the ophthalmologic unit with the diagnosis of acute angle closure attack. Thus, we discussed the way an ophthalmologist could make a difference between these two entities.