It affects vertical eye movements, a possible origin of a head injury, sometimes of little importance. The subject sees double, but if he tilts his head to the opposite side of the affected eye, he sees a single image, usually of unknown origin. It can be from: a) A head injury, due to a motorcycle accident, but sometimes even a relatively minor head injury b) diabetes c) a tumor, a bulge (aneurysm) in a cranial artery or multiple sclerosis. The affected eye cannot turn in and down, the person sees double images, one above and slightly to one side, it is difficult for him to go down the stairs, which requires looking in and down. However, double images are compensated for and eliminated by tilting the head away from the muscle of the affected eye. It is diagnosed by limited eye movement and CT.

Treatment: a) Eye exercises b) glasses with optical prisms. The paralysis usually resolves over time.