Table 1.

International classification of headache disorders (ICHD-3) criteria for a diagnosis of visual snow

A. Visual snow: dynamic, continuous tiny dots across the entire visual field, persisting for > 3 months

B. Additional visual symptoms of at least two of the following four types:

1. Palinopsia

2. Enhanced entoptic phenomena

3. Photophobia

4. Impaired night vision (nyctalopia)

C. Symptoms are not consistent with typical migraine visual aura

D. Symptoms are not better accounted for by another disorder