Non-provocative diagnostics of photosensitivity using visual evoked potentials.
OBJECTIVE
Photosensitive epilepsy (PSE) is the most common form of reflex epilepsy. Usually, to find out whether a patient is sensitive, he/she is stimulated visually with, e.g. a stroboscopic light stimulus at variable frequency and intensity until a photo paroxysmal response (PPR) occurs. The research described in this work aims to find whether photosensitivity can be detected without provoking a PPR.


METHODS
Twenty-two subjects, 15 with known photosensitivity, were stimulated with visual stimuli that did not provoke a PPR. Using an "evoked response representation", 18 features were analytically derived from EEG signals. Single- and multi-feature classification paradigms were applied to extract those features that separate best subjects with PSE from controls.


RESULTS
Two variables in the "evoked response representation", a frequency term and a goodness of fit term to a particular template, appeared to be best suited to make a prediction about the photosensitivity of a subject.


CONCLUSIONS
Evoked responses appear to carry information about potential PSE.


CONCLUSIONS
This result can be useful for screening patients for photosensitivity and it may also help to assess in a quantitative way the effectiveness of medical therapy.
Vermeulen
Joost
J
Quantitative Imaging Group, Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
Kalitzin
Stiliyan
S
Parra
Jaime
J
Dekker
Erwin
E
Vossepoel
Albert
A
da Silva
Fernando Lopes
FL
D000293:Adolescent; D000328:Adult; D002648:Child; D004569:Electroencephalography; D020195:Epilepsy, Reflex / Q000175:diagnosis*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods*