Visual Snow and its “Friends”
Visual snow is, of course, a visual symptom. We talk about it here because of its close relationship with migraine. Visual snow refers to what the patient sees – “snow” or “static” – in the case of persistent visual snow, it’s long term or even permanent.
Visual snow symptoms are often accompanied by migraine symptoms, and other issues as well, such as tinnitus, seeing flashes of light, and night blindness.
Although they certainly recognized the relationship between VSS and migraine, the evidence seems to suggest that they are overlapping but different conditions. In their words:
Consideration of the individual symptoms suggests that multiple factors are potentially involved in the development of VSS, including subcortical network malfunction and cortical hyperexcitation. Although there is substantial overlap between VSS and migraine syndromes in terms of co-occurring symptoms, both neurophysiological and neuroimaging studies provide substantial evidence of separate abnormalities of processing, supporting these as separate syndromes.
[source]
You can read a previous article comparing persistent migraine aura and visual snow here, although it should be noted that the researchers were talking not so much about a symptom of visual snow (which can have many causes), but of a specific syndrome.
The short story is that VSS probably has a complex origin – that is to say, more than one thing working together to cause it. Some of those things may also relate to migraine.
For more about visual snow, read Visual Snow and Persistent Migraine Aura – tests and treatments.
Treatments such as valproic acid, acetazolamide, lamotrigine and topiramate are typical for visual snow. But according to a recent paper, less than half of patients responded to the medications that were prescribed for them. Which means there’s a lot of work to do.
