The abducens nerve is the sixth cranial nerve and carries somatomotor fibers. It is responsible for the movement of the eyeball along with the oculomotor nerve and the trochlear nerve.

Anatomy

Innervation

The abducens nerve innervates the lateral rectus muscle and impairment of the abducens nerve leads to double vision.

Nuclei

The fibers of the abducens nerve originate from the nucleus of the abducens nerve, which is located in the pons at the floor of the fourth ventricle.

Course

The abducens nerve originates at the brainstem at the junction between the pons and the medulla oblongata. It passes through the Dorello's canal into the cavernous sinus. Within the cavernous sinus, the abducens nerve is the only cranial nerve that runs freely in the sinus and is not located in the wall of the cavernous sinus. Subsequently, the abducens nerve passes through the superior orbital fissure into the orbit.

Illustration

Cranial base Rhoton — Anatomical image of the base of the skull showing the gasserian ganglion and the junction of the trigeminal nerve into its three branches. The optic nerve, oculomotor nerve, trochlear nerve and abducens nerve are also shown. Illustration adapted from Albert Rhoton 2002 Neurosurgery.

Imaging

Abducens nerve and dorello canal — Visualization of the abducens nerve (CN VI) and the Dorello canal in axial T2 imaging.

Abducens nerve