Схема. Иннервация глазницы и глазного яблока = Innervation of the orbit and eyeball. Перевести на русский язык = Translate into Russian   Модификация: Gray H., (1821–1865), Drake R., Vogl W., Mitchell A., Eds. Gray's Anatomy for Students. Churchill Livingstone, 2007, 1150 p. см.: Анатомия человека: Литература. Иллюстрации. Примечание: Innervation Numerous nerves pass into the orbit and innervate structures within its bony walls. They include the optic nerve [II], the oculomotor nerve [III], the trochlear nerve [IV], the abducent nerve [VI], and autonomic nerves. Other nerves such as the ophthalmic nerve [V1] innervate orbital structures and then travel out of the orbit to innervate other regions.

Optic nerve The optic nerve [II] is not a true cranial nerve, but rather an extension of the brain carrying afferent fibers from the retina of the eyeball to the visual centers of the brain. It is surrounded by the cranial meninges, including the subarachnoid space, which extend as far forward as the eyeball. Any increase in intracranial pressure therefore results in increased pressure in the subarachnoid space surrounding the optic nerve. This may impede venous return along the retinal veins, causing edema of the optic disc (papilledema) which can be seen when the retina is examined using an ophthalmoscope. The optic nerve leaves the orbit through the optic canal. It is accompanied in the optic canal by the ophthalmic artery. Oculomotor nerve The oculomotor nerve [III] leaves the anterior surface of the brainstem between the midbrain and the pons. It passes forward in the lateral wall of the cavernous sinus. Just before entering the orbit the oculomotor nerve [III] divides into superior and inferior branches. These branches enter the orbit through the superior orbital fissure, lying within the common tendinous ring. Inside the orbit the small superior branch passes upward on the lateral side of the optic nerve to innervate the superior rectus and levator palpebrae superioris muscles. The large inferior branch divides into three branches: •    one passing below the optic nerve as it passes to the medial side of the orbit to innervate the medial rectus muscle; •    a second descending to innervate the inferior rectus muscle; •    the third descends as it runs forward along the floor of the orbit to innervate the inferior oblique muscle. As the third branch descends, it gives off the branch to the ciliary ganglion. This is the parasympathetic root to the ciliary ganglion and carries preganglionic parasympathetic fibers that will synapse in the ciliary ganglion with postganglionic parasympathetic fibers. The postganglionic fibers are distributed to the eyeball through short ciliary nerves and innervate the sphincter pupillae and ciliary muscles. Trochlear nerve The trochlear nerve [IV] arises from the posterior surface of the midbrain, and passes around the midbrain to enter the edge of the tentorium cerebelli. It continues on an intradural path arriving in and passing through the lateral wall of the cavernous sinus just below the oculomotor nerve [III]. Just before entering the orbit, the trochlear nerve ascends, passing across the oculomotor nerve [III] and enters the orbit through the superior orbital fissure above the common tendinous ring. In the orbit the trochlear nerve [IV] ascends and turns medially, crossing above the levator palpebrae superioris muscle to enter the upper border of the superior oblique muscle. Abducent nerve The abducent nerve [VI] arises from the brainstem between the pons and medulla. It enters the dura covering the clivus and continues in a dural canal until it reaches the cavernous sinus. The abducent nerve enters the cavernous sinus and runs through the sinus lateral to the internal carotid artery. It passes out of the sinus and enters the orbit through the superior orbital fissure within the common tendinous ring. Once in the orbit it passes out laterally to supply the lateral rectus muscle. Postganglionic sympathetic fibers Preganglionic sympathetic fibers arise from the upper segments of the thoracic spinal cord, mainly T1. They enter the sympathetic chain through white rami communicantes, and ascend to the superior cervical ganglion where they synapse with postganglionic sympathetic fibers. The postganglionic fibers are distributed along the internal carotid artery and its branches. The postganglionic sympathetic fibers destined for the orbit travel with the ophthalmic artery. Once in the orbit the fibers are distributed to the eyeball either by: •    passing through the ciliary ganglion, without synapsing, and joining the short ciliary nerves, which pass from the ganglion to the eyeball; or •    passing through long ciliary nerves to reach the eyeball. In the eyeball postganglionic sympathetic fibers innervate the dilator pupillae muscle. Ophthalmic nerve [V1] The ophthalmic nerve [V1] is the smallest and most superior of the three divisions of the trigeminal nerve. This purely sensory nerve receives input from structures in the orbit and from additional branches on the face and scalp. Leaving the trigeminal ganglion, the ophthalmic nerve [V1] passes forward in the lateral wall of the cavernous sinus inferior to the trochlear [IV] and oculomotor [III] nerves. Just before it enters the orbit it divides into three branches-the nasociliary, lacrimal, and frontal nerves. These branches enter the orbit through the superior orbital fissure with the frontal and lacrimal nerves outside the common tendinous ring, and the nasociliary nerve within the common tendinous ring. Lacrimal nerve The lacrimal nerve is the smallest of the three branches of the ophthalmic nerve [V1]. Once in the orbit it passes forward along the upper border of the lateral rectus muscle. It receives a branch from the zygomaticotemporal nerve, which carries parasympathetic and sympathetic postganglionic fibers for distribution to the lacrimal gland. Reaching the anterolateral aspect of the orbit, the lacrimal nerve supplies the lacrimal gland, conjunctiva, and lateral part of the upper eyelid. Frontal nerve The frontal nerve is the largest branch of the ophthalmic nerve [V1] and receives sensory input from areas outside the orbit. Exiting the superior orbital fissure, this branch passes forward between the levator palpebrae superioris and the periorbita on the roof of the orbit. About midway across the orbit it divides into its two terminal branches-the supra-orbital and supratrochlear nerves: •    the supratrochlear nerve continues forward in an anteromedial direction, passing above the trochlea, exits the orbit medial to the supra-orbital foramen, and supplies the conjunctiva and skin of the upper eyelid and the skin on the lower medial part of the forehead; •    the supra-orbital nerve is the larger of the two branches, continues forward, passing between the levator palpebrae superioris muscle and the periorbita covering the roof of the orbit, exits the orbit through the supra-orbital notch and ascends across the forehead and scalp, supplying the upper eyelid and conjunctiva, the forehead, and as far posteriorly as the middle of the scalp. Nasociliary nerve The nasociliary nerve is intermediate in size between the frontal and lacrimal nerves and is usually the first branch from the ophthalmic nerve. It is most deeply placed in the orbit, entering the area within the common tendinous ring between the superior and inferior branches of the oculomotor nerve [III]. Once in the orbit, the nasociliary nerve crosses the superior surface of the optic nerve as it passes in a medial direction below the superior rectus muscle. Its first branch, the communicating branch with the ciliary ganglion (sensory root to the ciliary ganglion), is given off early in its path through the orbit. The nasociliary nerve continues forward along the medial wall of the orbit, between the superior oblique and the medial rectus muscles, giving off several branches. These include: •    the long ciliary nerves, which are sensory to the eyeball but may also contain sympathetic fibers for pupillary dilation; •    the posterior ethmoidal nerve, which exits the orbit through the posterior ethmoidal foramen to supply posterior ethmoidal air cells and the sphenoidal sinus; •    the infratrochlear nerve, which distributes to the medial part of the upper and lower eyelids, the lacrimal sac, and skin of the upper half of the nose; •    the anterior ethmoidal nerve, which exits the orbit through the anterior ethmoidal foramen to supply the anterior cranial fossa, nasal cavity, and skin of the lower half of the nose. Ciliary ganglion The ciliary ganglion is a parasympathetic ganglion of the occulomotor nerve [III]. It is associated with the nasociliary branch of the ophthalmic nerve [V1] and is the site where preganglionic and postganglionic parasympathetic neurons synapse as fibers from this part of the autonomic division of the PNS make their way to the eyeball. The ciliary ganglion is also traversed by postganglionic sympathetic fibers and sensory fibers as they travel to the eyeball. The ciliary ganglion is a very small ganglion, in the posterior part of the orbit immediately lateral to the optic nerve and between the optic nerve and the lateral rectus muscle. It is usually described as receiving at least two, and possibly three, branches or roots from other nerves in the orbit. Parasympathetic root As the inferior branch of the oculomotor nerve [III] passes the area of the ciliary ganglion, it sends a branch to the ganglion (the parasympathetic root). The parasympathetic branch carries preganglionic parasympathetic fibers, which enter the ganglion and synapse with postganglionic parasympathetic fibers within the ganglion. The postganglionic parasympathetic fibers leave the ganglion through short ciliary nerves, which enter the posterior aspect of the eyeball around the optic nerve. In the eyeball the parasympathetic fibers innervate: the sphincter pupillae muscle, responsible for pupillary constriction; the ciliary muscle, responsible for accommodation of the lens of the eye for near vision. Sensory root A second branch (the sensory root), passes from the nasociliary nerve to the ganglion. This branch enters the posterosuperior aspect of the ganglion, and carries sensory fibers, which pass through the ganglion and continue along the short ciliary nerves to the eyeball. These fibers are responsible for sensory innervation to all parts of the eyeball. Sympathetic root The third branch to the ciliary ganglion is the most variable. This branch, when present, is the sympathetic root and contains postganglionic sympathetic fibers from the superior cervical ganglion. These fibers travel up the internal carotid artery, leave the plexus surrounding the artery in the cavernous sinus, and enter the orbit through the common tendinous ring. In the orbit they enter the posterior aspect of the ciliary ganglion, cross the ganglion, and continue along the short ciliary nerves to the eyeball. Sympathetic fibers to the eyeball may not enter the ganglion as a separate branch. The postganglionic sympathetic fibers may leave the plexus associated with the internal carotid artery in the cavernous sinus, join the ophthalmic nerve [V1] and distribute to the ciliary ganglion through the sensory root from the nasociliary nerve. Whatever their path, postganglionic sympathetic fibers reach the eyeball and innervate the dilator pupillae muscle.