Visual Snow: A New Disease Entity Distinct from Migraine Aura (S36.006)

Abstract

Objective: To define clinical criteria for visual snow. Background Visual snow is a disorder with continuous visual symptoms consisting of white and black dots in the entire visual field that can persist for years. Additional visual phenomena might be present. It has a major impact on patients9 quality of life. The literature confounds the condition with persistent visual aura in migraine. Treatment usually fails. Physicians may regard the problem is trivial or psychogenic. Design/Methods: Retrospective survey of patients with visual snow. We describe the clinical phenotype of affected patients and propose criteria for the diagnosis. Results: Patients ( n = 120) with a female:male ratio of 1:2.2 are reported. Mean age of onset was 16.8±10.9 years with a mean duration of 9.1±10.3 years. Of patients 106 (88%) had visual snow during the daytime and 117 (98%) at Additional visual symptoms were: floaters (73%), persistent after-images (63%), hard time seeing at (58%), little cells that travel on a wiggly path (57%), photophobia (54%), moving objects leave trails (48%), flashes (44%), and swirls with eyes closed (41%). Most disturbing were visual snow, floaters and hard time seeing at night. Of patients 92% had no response to medication. Substance abuse was present in 40% of patients (LSD in 5%). Requiring at least one, two or three of the additional visual symptoms to make the diagnosis reduced the sensitivity by 3%, 10% and 21%. All standard tests were normal. Conclusions: (i) Visual snow, or Positive Persistent Visual Disturbance, is a unique disease entity presenting clinically distinct from migraine with aura.(ii) Criteria are: visual snow during daytime or at night plus at least one of the following: floaters, persistent after-images, hard time seeing at night, little cells that travel on a wiggly path, photophobia, moving objects leave trails, flashes, and swirls with eyes closed.(iii) Currently, the etiology is unknown. Supported by: Deutsche Forschungsgemeinschaft SCHA 1676/1-1. Disclosure: Dr. Schankin has nothing to disclose. Dr. Maniyar has nothing to disclose. Dr. Hoffmann has nothing to disclose. Dr. Chou has nothing to disclose. Dr. Goadsby has received personal compensation for activities with Allergan, Inc., Amgen Inc, Colucid, MAP Pharmaceuticals, MSD, Neuralieve, Neuraxon, ATI, Boehringer Ingelheim Pharmaceuticals, Inc., Boston Scientific, Coherex, Eli Lilly & Company, Medtronic, Inc., Linde, Bristol-Myers Squibb Company, Pfizer Inc, and Air Products. Dr. Goadsby has received research support from GlaxoSmithKline, Inc., Amgen Inc, MSD, Neuralieve, and Boston Scientific.