Case Report: Transformation of Visual Snow Syndrome From Episodic to Chronic Associated With Acute Cerebellar Infarct

Abstract

Visual snow syndrome is a novel neurological condition characterized by a panfield visual disturbance associated with several additional symptoms. Although it is usually a continuous and primary disorder, cases of intermittent visual snow have been described in the literature, as well as rare secondary forms. This report is the first description of a case of intermittent visual snow syndrome, which transformed into a persistent form following a posterior circulation stroke due to vertebral artery dissection. At 1 and 2 years after experiencing the acute cerebellar infarct, the patient's only neurological sequalae was visual snow. This case provides a description of how visual snow syndrome may be caused by an underlying brain disorder, and highlights the importance of the cerebellum in the pathophysiology of this relatively unknown condition. It further shows evidence of how existing predispositions might be relevant to the development of visual snow, in certain subjects and following specific circumstances.

Visual Snow: A Review on Pathophysiology and Treatment

“…The changes in the cerebellum might represent a broader network-like disorder, but when corrected for age, sex, handedness, and duration of disease, were not significant [ 19 ]. Another argument for cerebellar participation in VSS pathophysiology is shown in a case report describing a transformation from episodic to chronic VSS after infarction of the right superior cerebellar artery territory [ 23 ].…”

Visual snow syndrome and migraine: a review

“…Prospective studies have shown that VSS symptoms tend to remain stable over time and are not expected to cease [ 10 , 11 ]. The visual snow itself can, however, manifest episodically, and either remain as an ictal disorder or later evolve into the classic form of VSS [ 12 – 14 ]. In these cases visual snow should carefully be distinguished from visual aura or other visual phenomena associated with migraine [ 15 ].…”

The phenomenon of “visual snow”: clinical and pathophysiological correlations, differential diagnosis and treatment (literature review)

“…F. Puledda и соавт. [2] опубликовали описание случая трансформации эпизодического ВС в постоянный у 44-летнего мужчины после развития инсульта в вертебробазилярном бассейне на фоне диссекции правой позвоночной артерии. И наоборот, имеются данные, согласно которым в течение недели после геморрагического инсульта в области левого таламуса последовало кратковременное разрешение СВС у 25-летней женщины [21].…”

“…Случай СВС на фоне ишемического инсульта в гемисфере мозжечка, описанный F. Puledda и соавт. [2], указывает на вовлеченность мозжечка в патофизиологию СВС. Как известно, задняя часть мозжечка играет ключевую роль не только в двигательных функциях, но также в сенсомоторной и когнитивной интеграции.…”