Head and Neck Anatomy: Part III – Cranial Nerves
Course Number: 598
Course Contents
V1 – Ophthalmic Nerve
Figure 13. Cranial Nerve V1 – Ophthalmic Nerve (shown in blue)
This is a purely sensory nerve that supplies the skin over the upper 1/3rd of the face and then in a narrow band down the center of the nose including the philtrum of the upper lip through its frontal and lacrimal branches. It also supplies sensation to some of the nasal mucous membranes and many structures of the eye including the cornea through its nasociliary branch. The lacrimal branch in addition travels to the lacrimal gland not only providing sensory fibers but also carrying parasympathetic fibers that originate in the facial nerve but hitchhike on branches of the trigeminal. In figure 15 below, you can see the branches and can also see the communicating branch with the zygomatic nerve labeled. This small branch is carrying fibers that while they started in the facial nerve are in branch of the second division of the trigeminal prior to connecting to the lacrimal branch. We will discuss that further as we look at that division and again with the facial nerve.
Figure 14. Cranial Nerve V1 – Ophthalmic Nerve
Figure 15.
The three branches of CN V join together in the vicinity of the superior orbital fissure and the entire nerve enters the trigeminal ganglion where the bodies of the sensory neurons are located. The axons then pass into the CNS.