Abducens nerve
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The sixth out of twelve cranial nerves, the abducens nerve innervates the lateral rectus muscle - this means that the action of this nerve controls each eye's ability to abduct (move away from the midline). The abducens nerve emerges from the ipsilateral abducens nucleus between the caudal pons beneath the floor of the fourth ventricle and the medulla (the pontomedullary junction). The abducens nerve exits the skull through the superior orbital fissure (one of the holes in the skull behind the eye).
Looking for a 6th nerve palsy is a good screening sign in children with suspected meningitis. As the abducens emerges near the bottom of the brain, it is often the first nerve compressed when there is any rise in intracranial pressure. The lateral rectus muscle of the eye that the abducens nerve innervates is opposed by the action of the medial rectus muscle. Damage to the abducens nerve causes medial strabismus as the individual is no longer able to control lateral eye movement via the lateral rectus motor neurons.