Photic stimulation with physiological light driving intracranial electrodes in epilepsy patients and its pathological photo-effect

Objective To report the response of an epilepsy patient to photic stimulation of intracranial electrodes. Methods A patient with refractory epilepsy was assessed with SEEG before operation.Electrodes were implanted into different sites of occipital-temporal lobes.The opened or closed eyes of the patient were stimulated with light source at the frequency of 1-40Hz. Results All the significant contacts of physiological light-driven electrodes,located in the medial occipital lobe,were close to the calcarine fissure.The photo-effect was different at different contacts of intracranial electrodes due to different distances to the calcarine fissure.No pathological photo-effect was observed. Conclusion Much precise physiological information on the physiological visual system of epilepsy patients can be obtained by implanting electrodes into their brain,especially into the medial occipital lobe.