[Is it possible to compensate for visual field defects?]

Is it possible for a driver to compensate for visual field defects by skill along with eye and head movements? Monocular field defects with a normal second eye are no problem, because a normal binocular visual field is adequate for all areas of traffic. A total bitemporal hemianopia creates a special situation, because the patient loses a three-dimensional space behind a vertical line through the point of fixation. He may have no binocular visual field. In this case the ability to participate in certain traffic situations may be limited with reduced risk profile. A real problem is posed by defects in the binocular visual field, e.g., due to lesions of the suprachiasmal visual pathway or due to ocular diseases causing damage to both eyes (e.g., glaucoma, diabetic retinopathy, etc.). Such defects usually cannot be compensated for, neither by skill nor by eye or head movements. Saccadic eye movement training and other procedures are only of limited help. These procedures may provide some compensation for daily use; a complete restoration of the ability to participate in traffic is not possible. Rare exceptions may be patients with damage to the visual pathway acquired peri- or postnatally or in early childhood when there is still enough plasticity in the visual system to develop mechanisms of compensation by completely changing the system of eye and head movements.