photoparoxysmal response
An abnormal EEG response to intermittent photic stimulation characterized by spike-wave discharges.
Full Definition
A photoparoxysmal response (PPR) is an abnormal electroencephalographic finding consisting of spike-wave complexes triggered by intermittent photic stimulation during EEG recording. The response typically occurs at specific flash frequencies and may be generalized or focal. PPR is classified into different grades based on the extent and persistence of the abnormal activity. This finding is associated with photosensitive epilepsy and indicates an increased risk of seizures triggered by flashing lights, television screens, or video games. The presence of PPR influences treatment decisions and lifestyle recommendations for patients.
Usage
Usage note: Avoid confusing with normal 'photic driving' which is a physiological response.
In Context
- "Grade IV photoparoxysmal response was elicited at 15-18 Hz flash frequency." — EEG activation procedure report
- "The patient demonstrated photoparoxysmal response during intermittent photic stimulation, confirming photosensitive epilepsy." — Epilepsy evaluation report