Photosensitive patients: symptoms and signs during intermittent photic stimulation and their relation to seizures in daily life.

Abstract

SUMMARY Thirty six patients were studied with a classical photoparoxysmal EEG response to intermittent photic stimulation (IPS). Clinical observations and complaints reported by patients during standardised IPS were recorded and compared with historical data. Twenty seven patients experienced impaired consciousness or showed motor phenomena such as involuntary opening of the eyes or jerking on one or both sides of the body. Twenty five patients had sensations such as pain in the eyes, jerking etc. There existed no relation between the duration of the evoked discharges (0 5-3 seconds) and observed signs or complaints. In 11 instances the clinical features found during IPS were not reported in a history taken from the patient and relatives. In the case of spontaneous epileptiforn EEG discharges it is generally accepted that there is a relation between the duration of the discharge and the occurrence of observable clinical features. If generalised spike-wave discharges last less than 3 seconds, they often pass unnoticed by the patient and the observer. " 12 However, it is not known whether photically-induced epileptiform activity differs in this respect from spontaneous discharges. In a previous study of 38 photosensitive patients we found that 39% reported various forms of ocular discomfort (sore eyes, headache, etc.) induced by potentially epileptogenic stimuli, such as disco lighting and the sun shining through trees or on water.13 It is unknown whether subjective complaints during IPS' "1 have any relation to clinical features during IPS or to visually-induced seizures in daily life. We have therefore prospectively examined an unselected group of photosensitive patients, with particular attention to subjective and objective clinical events during IPS.

Video game induced seizures.

“…Photoconvulsive response on intermittent photic stimulation (12-30 Hz), pattern and video game testing Photoconvulsive response on video game testing only Photoconvulsive response on video game testing only Photoconvulsive response on intermittent photic stimulation (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) Hz). Occipital spike on pattern testing Photoconvulsive response on intermittent photic stimulation (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) Photoconvulsive response on intermittent photic stimulation (3-30 Hz) Photoconvulsive response on intermittent photic stimulation (wide range of frequencies) Photoconvulsive response on idiopathic generalised epilepsy (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) photosensitive to intermittent photic stimulation and may also experience televisio...…”

The Photoparoxysmal Response: The Probable Cause of Attacks during Video Games

“…18 In 69% there were sensations such as pain in the eyes, and in nearly one third these latter symptoms had not been previously mentioned by the patients or their relatives.…”

Visual Sensitivity and Epilepsy: A Proposed Terminology and Classification for Clinical and EEG Phenomenology

“…Some individuals may complain of subjective symptoms when they are exposed to photic stimuli, especially IPS (35). Some of these symptoms are normal phenomena, due to the effect of intense light stimuli.…”

“…In exceptional cases, focal myoclonic (FM) jerks (e.g., in one hand, arm, or hemiface) can be evoked by IPS (35,42). Consciousness is retained.…”

“…To rule out the possibility of minor visually induced seizures (see earlier), a detailed clinical history should be taken with the emphasis on subtle, subjective symptoms. Ocular discomfort, such as pain in the eyes or blurring of vision, can be considered an ictal symptom (7,35). A distinction between an ictal visual aura (or complaint) and atypical complaints, such as tears and seeing diffuse colors, can be difficult to draw.…”