Cross polarized spectacles in photosensitive epilepsy.

PURPOSE: To investigate the role of cross polarized spectacles in the treatment of photosensitivity demonstrable by EEG.

METHOD: Patients receiving an EEG who tested positive for photosensitivity were invited to participate in the study. The most sensitive light flicker frequency causing a photic response was determined for each patient. Stimulation was repeated with 2 different pairs of spectacles--1 conventionally polarized and the other cross polarized. An EEG was obtained in each case and reported by a neurophysiologist who was unaware of the identity of the 2 types of spectacles.

RESULTS

We tested 19 patients, 8 to 18 years of age. Two patients did not benefit from either pair of glasses. In 17 patients, the photic response was greatly diminished or eliminated by polarizing spectacles. In 1 patient, conventional polarized glasses helped, but the cross polarized spectacles did not. In 6 patients, both types of spectacles were equally effective; in 10 patients, cross polarized spectacles were more effective than conventionally polarized spectacles.

CONCLUSION

The role of cross polarized spectacles in the management of photosensitivity in a clinical situation merits further investigation.