What is Your Abducent Nerve?

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Structure and Function

What is your abducent nerve? The abducent nerve is one of the nerves leading to the eye. It is one of the cranial nerves and is commonly referred to as the “sixth nerve”, or simply “VI”, since it is considered to be the sixth cranial nerve. It’s sole purpose is to supply the lateral rectus muscle of the eye. This muscle allows the eye to be pulled away from the center of the body. Damage to the nerve can result in damage to how this nerve operates, which in turn will result in difficulty with vision.

It begins its journey in the nucleus of the rhomboid fossa, traveling through various areas including a sinus cavity. The long journey that this nerve takes may leave it vulnerable to damage, particularly if the frontal lobe is damaged. Damage to the nerve may result in what is known as abducent nerve palsy, which is a disease in which the end result is poor functioning of the lateral rectus muscle.

Some of the signs of this type of damage may be an inability to maintain focus on objects that are directly in front of the eye. This because the muscle is unable to maintain stability of the position of the eye. The result may be that eye tends to “wander” to one side or the other. To understand this, consider the analogy below.

Imagine a ball with rubber bands attached to it in even spaced placement. (You need to imagine as well that the rubber bands are attached to a steady object to understand this.) The rubber would need to be taut in order to hold this ball in place. If one of the bands on either side of the ball are loose, this will cause the ball to turn to the opposite side as the tension holding it in place is no longer there. The muscles that control the eye work in a similar fashion. If they are all doing their job, it is because the nerves leading to them are all doing their jobs. When one of those nerves fails to work properly, so does the muscle. In the case of the abducent nerve, the eye would wander towards the center of the body. The person would then need to turn so that the eyes were looking out the side instead of straight ahead in order to focus on one object. Without doing this, the person may have what is known as double vision.