VEP (Visual Evoked Potential): Usually, vision examination in children confronts some difficulties, therefore special tests such as VEP and ERG are performed. These two tests can provide Ophthalmologists the information of the visual pathways from retina via the optic nerves to the visual cortex of the brain. When a light flashes oran object movies or suddenly appear in the visual field, anelectrical response is emittedfrom the visual cortex of the brain. VEP is based on measuring this electrical response. To perform this test, the electrodes are placed on the back of the head.