The abducent nerve, also known as the sixth cranial nerve or CN VI, is a motor nerve that controls the lateral rectus muscle of the eye. This muscle is responsible for moving the eye outward, away from the midline of the face.
The abducent nerve originates from the brainstem, specifically from the pontine tegmentum. It then passes through the cavernous sinus, a venous space located behind the eye, and enters the orbit through the superior orbital fissure. Within the orbit, the abducent nerve supplies the lateral rectus muscle, which is essential for horizontal eye movements.
Damage to the abducent nerve can cause weakness or paralysis of the lateral rectus muscle, leading to a condition called abducens nerve palsy. This can result in double vision, or diplopia, when attempting to look towards the affected side. Abducens nerve palsy can be caused by a variety of factors, including trauma, infection, inflammation, and tumors. Treatment depends on the underlying cause and may include medications, surgery, or vision therapy to manage double vision.