What is Abducens nerve palsy?
Abducens (sixth cranial) nerve palsy is the most common ocular motor paralysis in adults and the second-most common in children. The abducens nerve controls the lateral rectus muscle, which abducts the eye. Abducens nerve palsy causes an esotropia due to the unopposed action of the antagonistic medial rectus muscle.
What is the origin of the abducens nerve?
The abducens nerve originates from neuronal cell bodies located in the ventral pons. These cells give rise to axons that course ventrally and exit the brain at the junction of the pons and the pyramid of the medulla. The nerve of each side then travels anteriorly where it pierces the dura lateral to the dorsum sellae.
What is right Abducens nerve palsy?
Sixth nerve palsy occurs when the sixth cranial nerve is damaged or doesn’t work right. It’s also known as the abducens nerve. This condition causes problems with eye movement. The sixth cranial nerve sends signals to your lateral rectus muscle. This is a small muscle that attaches to the outer side of your eye.
What is the course of abducens nerve?
Course. The abducens nerve originates from a set of neural cells that are found in the ventral aspect of the pons. It then emerges from the brainstem at the pontomedullary junction to enter the subarachnoid space, coursing upward between the pons and clivus to enter the Dorello canal.
What type of nerve is the abducens nerve?
somatic motor nerve
The abducens nerve is a purely somatic motor nerve, It has no sensory function. It innervates the lateral rectus muscle, an extraocular muscles of the eye, which is responsible for the abduction of the eyes on the same (ipsilateral) side.
How does the abducens nerve work?
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.
Where is the abducens nerve?
The abducens nerve leaves the brainstem at the junction of the pons and the medulla, superior to the pyramid and medial to the facial nerve. It runs upwards and forwards from this position to reach the eye. The nerve enters the subarachnoid space when it emerges from the brainstem.
What is the main function of the abducens nerve?
The abducens nerve is a purely somatic motor nerve, It has no sensory function. It innervates the lateral rectus muscle, an extraocular muscles of the eye, which is responsible for the abduction of the eyes on the same (ipsilateral) side.
Where is abducens nerve located?
pons
Of all the cranial nerves, the abducens nerve has the second longest intracranial course. It is located in the pons at the floor of the fourth ventricle, at the same level as the facial colliculus. In fact, the axons of the facial nerve loop around the posterior aspect of the abducens nucleus.
Which cranial nerve is the longest?
The vagus nerve
The vagus nerve (cranial nerve [CN] X) is the longest cranial nerve in the body, containing both motor and sensory functions in both the afferent and efferent regards.
What is the main function of abducens nerve?
Function. The abducens nerve is a purely somatic motor nerve, It has no sensory function. It innervates the lateral rectus muscle, an extraocular muscles of the eye, which is responsible for the abduction of the eyes on the same (ipsilateral) side.