Visually-provoked seizures: Consensus of the Epilepsy Foundation Working Group

Abstract

In 2005, the Epilepsy Foundation published an expert consensus (Epilepsia 2005; 46:1423–1425) on actions to minimize risks of visually-provoked (photosensitive) seizures (VPS). Since then, technology, scientific information, and experience have greatly expanded. An international expert panel convened by the Epilepsy Foundation collated literature, information, and opinions regarding VPS. Consensus guidelines are divided into advice for: patients and families, clinicians, designers of video games, architects, and regulatory agencies. No attempt was made to develop a formal systematic review. Patients are advised about symptoms and epilepsy syndromes that relate to VPS. Commonly used medications and useful behavioral modifications are reviewed. Clinicians are advised on an approach to events that are concerning for VPS, including how to use history and electroencephalography (EEG) to assess whether an event was a seizure (vs another neurologic symptom) and what visual stimuli (light or patterns) provoked it. The utility of magnetic resonance imaging (MRI) to assess for an epileptogenic lesion, routine blood tests, and genetic studies is discussed. Media designers of video games, movies, TV productions, web videos, and artificial or virtual reality images are advised to avoid bright flashing patterns in the 10–20 Hz range, repetitive color flashes, and oscillating or static stripes of ~1–8 cycles per visual degree. Signal analysis or trained human inspectors can identify provocative visual patterns. Architects and designers of public spaces should be aware that some striped patterns can provoke seizures. Government and regulatory agencies require screening of potentially provocative media in some nations. VPS are both an individual and public health problem. The Epilepsy Foundation encourages further research and efforts to minimize risks of seizures provoked by visual stimuli.