Television, Computers & Epilepsy
DR. PRITHIKA CHARY, EPICENTRE, CHENNAI

PHOTOSENSITIVE EPILEPSY

• Seizures brought on by flickering light

• TV, Discos, Flashing VDU graphics,

• Sunlight flickering through leaves,

• Striped patterns on grill, gratings, clothes, furnishing fabrics

• 4% of patients with photosensitive epilepsy

TELEVISION & SEIZURES

• Refresh rate is 50 to 60/second

• In colour TV it is a row of dots rather than lines

• At a time only half the lines are seen ie. 25 lines per second

• Obvious when sitting very close to TV with a large screen

• Newer TVs with 100Hz refresh rate are safer

SEIZURE INDUCING PATTERNS

• Stripes of 1/8 “ three feet from the eye

• Stripes of 1/4” six feet from the eye

• Moving striped or trellis patterns

• Rarely reading can provoke seizures as the stripes formed by printed text form a troublesome pattern

• Flashing graphics and lights eg car headlights

TIPS FOR SAFE TV/VDU USAGE

• Small screen ideal 12 to 14 inches for playing video games & computer usage

• TV should produce a stable picture

• Colour & Black & White do not differ

• Viewing distance should be four times the width of the screen while playing video games or watching TV.

• Moderately lit room with dim picture preferable

TIPS FOR SAFE TV/VDU USAGE

• Moving graphics as in video games provoke seizures

• Colour content of the picture may be important eg: red is worse than blue

• Striped patterns have high potential to cause seizures especially if the pattern is moving

• The picture should be stable and not roll or zig zag

EEG & PHOTOSENSITIVE EPILEPSY

• EEG can diagnose photosensitive epilepsy when photic stimulation at varying frequencies of flashes are given.

• Response may be photoparoxysmal, photoconvulsive, etc.

• This type of epilepsy can be controlled with Sodium Valproate and sensible viewing of TV/VDU, etc.