Path
The ophthalmic nerve supplies branches to the cornea, ciliary body, and iris; to the lacrimal gland and conjunctiva; to the part of the mucous membrane of the nasal cavity; and to the skin of the eyelids, eyebrow, forehead and nose.
It is the smallest of the three divisions of the trigeminal, and arises from the upper part of the trigeminal ganglion as a short, flattened band, about 2.5 cm. long, which passes forward along the lateral wall of the cavernous sinus, below the oculomotor and trochlear nerves; just before entering the orbit, through the superior orbital fissure, it divides into three branches, lacrimal, frontal, and nasociliary.
The frontal branch passes through the orbit superiorly, then reenters the frontal bone briefly before exiting above the orbit through the supraorbital foramen and the supratrochlear notch to provide sensory innervation for the skin of the forehead and scalp. The lacrimal nerve passes through the orbit superiorly to innervate the lacrimal gland. The nasociliary branch gives off several sensory branches to the orbit and then continues out through the anterior ethmoidal foramen, where it enters the nasal cavity and provides innervation for much of the anterior nasal mucosa. It also gives off a branch which exits through the nasal bones to form the external nasal branch.
The ophthalmic nerve is joined by filaments from the cavernous plexus of the sympathetic, and communicates with the oculomotor, trochlear, and abducent nerves; it gives off a recurrent (meningeal) filament which passes between the layers of the tentorium.
Read more about this topic: Ophthalmic Nerve
Famous quotes containing the word path:
““O what unlucky streak
Twisting inside me, made me break the line?
What was the rock my gliding childhood struck,
And what bright unreal path has led me here?””
—Philip Larkin (1922–1986)
“A few hours’ mountain climbing turns a rogue and a saint into two roughly equal creatures. Weariness is the shortest path to equality and fraternity—and liberty is finally added by sleep.”
—Friedrich Nietzsche (1844–1900)
“What is the use of going right over the old track again? There is an adder in the path which your own feet have worn. You must make tracks into the Unknown.”
—Henry David Thoreau (1817–1862)