Anatomy Nerves The Anatomy of the Abducens Nerve Involved in looking out the corner of your eye and double vision By Adrienne Dellwo Adrienne Dellwo LinkedIn Adrienne Dellwo is an experienced journalist who was diagnosed with fibromyalgia and has written extensively on the topic. Learn about our editorial process Updated on March 17, 2020 Medically reviewed by Keri Peterson, MD Medically reviewed by Keri Peterson, MD Facebook LinkedIn Twitter Keri Peterson, MD, is board-certified in internal medicine and has her own private practice on the Upper East Side of Manhattan. She holds appointments at Lenox Hill Hospital and Mount Sinai Medical Center. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Anatomy Function Associated Conditions Rehabilitation The abducens nerve, sometimes called the abducent nerve, is responsible for the movement of the lateral rectus muscle, which allows your eye to rotate away from the center of your body and look to the left or right. The abducens is the sixth cranial nerve (CN VI). This nerve has only a motor function and lacks a sensory function. The abducens is considered an extraocular nerve, which literally means “outside of the eye.” Along with the oculomotor nerve (CN III) and the trochlear nerve (CN IV), it provides movement to the muscles around the eyeball rather than attaching to the eye itself. Anatomy Humans have 12 cranial nerves that exist in generally symmetrical pairs, one on each side of your head. Unless it’s necessary to distinguish one side from the other (such as if one of them is damaged), each pair is most often referred to as a single nerve. The cranial nerves are different from the rest of your nerves, which originate in the spinal cord. Cranial nerves originate from the brain and brainstem and perform functions in your face and throat. The 12 Cranial Nerves Structure and Location The abducens nerve emerges from the brainstem, which sits low in the back of your brain and connects to the spinal column. The specific area the nerve comes from is called the abducens nucleus. It leaves the brainstem and passes through an area of the brain called the subarachnoid space. From there, it travels upward and pierces a tough membrane, called the dura mater, which envelops the brain and spinal cord. It then runs between the dura and the skull through a space called the Dorello canal and takes a sharp turn toward your face to move into the cavernous sinus. There, it follows the internal carotid artery to where it can enter the orbit (the eye socket) through the superior orbital fissure. Finally, it connects to the lateral rectus muscle of the eye. The lateral rectus muscle connects to the outside of your eye, right in line with the pupil. A small branch of the abducens nerve connects to the contralateral medial rectus muscle. Anatomical Variations Many nerves have known anatomical variations. These are important for doctors to know so they can make proper diagnoses and especially during surgery, so they can avoid damaging a nerve with an irregular course. The abducens nerve has a few known variations. In some people, the nerve may: Send out abnormal branches. Take an unusual course from the brainstem to the lateral rectus muscle. Be doubled or even tripled in sections or along its entire course. Function The function of the abducens nerve is quite simple and straightforward: It moves the eye outward (abduction) so you can look to the side.Via the contralateral medial rectus muscle, it coordinates the simultaneous side-to-side movement of your eyes. Associated Conditions The abducens nerve travels farther through the skull than any other cranial nerve. This leaves it vulnerable to injury at multiple points. Damage to this nerve is called abducens nerve palsy or sixth cranial nerve palsy. Downward pressure on the brainstem is a common cause of abducens damage. Other causes include: TraumaAneurysmIschemia (loss of blood flow)InfectionInflammation due to injury or illnessStrokeMetabolic disease (i.e., Wernicke disease)Demyelinating lesionsCarcinomatous meningitisBasal skull fractureDamage to the orbit (eye socket)Damage from surgery or other medical procedures, especially involving the cavernous sinus In people with diabetes, poorly controlled blood sugars are a significant risk factor for abducens nerve palsy, as are certain problems in the cavernous sinus. (However, diabetic neuropathy and cavernous sinus problems are likely to affect many nerves beyond the abducens.) In many cases, possibly as many as 30%, the cause is never identified. In adults, this nerve is the most frequently damaged nerve of the eye, and it’s the second most common one for children to damage. (The fourth cranial nerve, the trochlear nerve, is the most commonly injured in kids.) The primary symptom of abducens nerve palsy is an inability to abduct the eye, which can cause it to droop inward, as if “crossed.” This can result in diplopia, which is the clinical term for double vision, because the eyes aren’t looking in the same direction. Double Vision Causes and Treatment Rehabilitation The treatment and management of abducens nerve palsy is different for children than it is for adults. Treatment in Children In children, treatment focuses on training the eye to restore proper movement. This can be accomplished in several ways, including: Patching one eye at a time and periodically alternating, which also helps prevent “lazy eye” in the unaffected side Prism therapy to prevent double vision Botulism injections If other treatments fail, surgery Treatment in Adults The first-line treatment for abducens nerve palsy in adults is, most often, wait and see. Most cases resolve on their own. When that doesn’t happen, the treatment is determined based on what caused the palsy. Treatment may include: Steroids to relieve inflammationSurgery or lumbar puncture to relieve pressureTreatments similar to those for children, with the exception of alternate patching 3 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Nguyen J, Duong H. Anatomy, head and neck, eye nerves. In:StatPearls. Wang JMH, Edwards BA, Loukas M, Oskouian RJ, Tubbs RS. Supernumerary abducens nerves: a comprehensive review. World Neurosurg. 2018;112:39–45. doi:10.1016/j.wneu.2017.11.052 Romero FR, Ramos JG, Chaddad-Neto F, Bethencourt JM, de Oliveira E. Microsurgical anatomy and injuries of the abducens nerve. Arq Neuro-Psiquiatr. 2009;67(1):96–101. doi:10.1590/s0004-282x2009000100022 Additional Reading Coquet T, Lefranc M, Chenin L, Foulon P, Havet É, Peltier J. Unilateral duplicated abducens nerve coursing through both the sphenopetroclival venous gulf and cavernous sinus: a case report [published correction appears in Surg Radiol Anat. 2018 Nov;40(11):1327]. Surg Radiol Anat. 2018;40(7):835–840. doi:10.1007/s00276-018-2003-7 Graham C, Mohseni M. Abducens nerve (CN VI) palsy. StatPearls. Nam YS, Kim IB, Shin SY. Detailed anatomy of the abducens nerve in the lateral rectus muscle. Clin Anat. 2017;30(7):873–877. doi:10.1002/ca.22918 Nguyen V, Varacallo M. Neuroanatomy, cranial nerve 6 (abducens). StatPearls. Pizzolorusso F, Cirotti A, Pizzolorusso G. Anatomic variation of the abducens nerve in a single cadaver dissection: the "petrobasilar canal". Acta Neurochir (Wien). 2017;159(4):677–680. doi:10.1007/s00701-017-3096-1 By Adrienne Dellwo Adrienne Dellwo is an experienced journalist who was diagnosed with fibromyalgia and has written extensively on the topic. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit