The lacrimal nerve is the smallest branch of the

ophthalmic nerve The ophthalmic nerve (V1) is a sensory nerve of the face. It is one of three divisions of the trigeminal nerve (CN V). It has three branches that provide sensory innervation to the eye, the skin of the upper face, and the skin of the anterior sc ...

(V₁), itself a branch of the

trigeminal nerve In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chew ...

(CN V). The other branches of the ophthalmic nerve are the

frontal nerve The frontal nerve is the largest branch of the ophthalmic nerve (V1), itself a branch of the trigeminal nerve (CN V). It supplies sensation to the skin of the forehead, the mucosa of the frontal sinus, and the skin of the upper eyelid. It may b ...

and

nasociliary nerve The nasociliary nerve is a branch of the ophthalmic nerve, itself a branch of the trigeminal nerve (CN V). It is intermediate in size between the other two branches of the ophthalmic nerve, the frontal nerve and lacrimal nerve. Structure The na ...

Structure

The lacrimal nerve branches from the ophthalmic nerve immediately before traveling through the superior orbital fissure to enter the orbit. It travels through it lateral to the

outside the annulus of Zinn. After entering, it travels anteriorly along the lateral wall with the

lacrimal artery The lacrimal artery is an artery of the orbit. It is a branch of the ophthalmic artery. It accompanies the lacrimal nerve along the upper border of the lateral rectus muscle, travelling forward to reach the lacrimal gland. It supplies the lacri ...

, above the upper margin of the lateral rectus. It receives a communicating branch from the

zygomatic nerve The zygomatic nerve is a branch of the maxillary nerve, itself a branch of the trigeminal nerve (CN V). It travels through the orbit and divides into the zygomaticotemporal and the zygomaticofacial nerve. It provides sensory supply to skin over ...

which carries the postganglionic parasympathetic axons from the

pterygopalatine ganglion The pterygopalatine ganglion (aka Meckel's ganglion, nasal ganglion, or sphenopalatine ganglion) is a parasympathetic ganglion found in the pterygopalatine fossa. It is largely innervated by the greater petrosal nerve (a branch of the facial n ...

. It travels through the lacrimal gland giving sensory and parasympathetic branches to it and then continues anteriorly as a few small sensory branches.

Function

The lacrimal nerve provides sensory innervation to the

lacrimal gland The lacrimal glands are paired exocrine glands, one for each eye, found in most terrestrial vertebrates and some marine mammals, that secrete the aqueous layer of the tear film. In humans, they are situated in the upper lateral region of each or ...

conjunctiva The conjunctiva is a thin mucous membrane that lines the inside of the eyelids and covers the sclera (the white of the eye). It is composed of non-keratinized, stratified squamous epithelium with goblet cells, stratified columnar epithelium ...

of the lateral upper

eyelid An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. The human eye ...

and superior fornix, the skin of the lateral forehead, scalp and lateral upper eyelid. It also provides parasympathetic innervation to the lacrimal gland from the communicating branch it receives from the

Additional images

File:Gray776.png, Superior view of the nerves of the orbit. The lacrimal nerve is seen branching from the ophthalmic nerve. File:Gray784.png, Sensory innervation to the skin of the head and neck. The cutaneous distribution of the lacrimal nerve can be seen above the eye in the green area. File:Gray894.png, Anterior view of the orbit and tarsal plates. The lacrimal nerve can be seen exiting the orbit superolaterally after it supplies the lacrimal gland. File:Slide7abab.JPG, Superior view of a dissection of the left orbit. The lacrimal nerve is visible innervating the lacrimal gland.

References

{{Authority control Ophthalmic nerve