[Characterization of a German cohort with visual snow syndrome]

Visual snow is a disorder of visual perception that is manifested as a constant flickering or "TV-like" noise in the entire visual field. Visual snow syndrome (VSS) describes a combination with other additional visual symptoms, such as sensitivity to light, afterimages, night blindness and entoptic phenomena. Cases of VS have been described in the literature using a wide variety of terms, often misunderstood as persistent migraine aura. Established diagnostic criteria have existed for more than 10 years now; however, the pathophysiology is still incompletely understood. The exact prevalence also remains unknown and high numbers of unreported cases are suspected. This is the first detailed description of a cohort of VSS patients from Germany.

Patients with VSS from several studies conducted at our center were pooled and retrospectively evaluated with respect to demographic, epidemiological and clinical data.

In this study 66 patients with VSS were included (age 31.3 ± 8.3 years, 30 women). The most commonly associated visual symptoms were photophobia (67%) and afterimages (65%). Of the patients 36 (54%) had comorbid migraine of whom 25 (70%) had migraine with aura, 26 (39%) reported depressive symptoms and 32 (48%) symptoms of an anxiety disorder. Tinnitus was reported by 32 (48%) patients.

The characteristics of the German cohort described here are similar to other international descriptions. Due to the frequent psychological comorbidity there is still a risk of psychosomatic stigmatization.