Infratrochlear nerve

The infratrochlear nerve is a small nerve that is a branch of the ophthalmic nerve, which is itself a branch of the trigeminal nerve. It is responsible for providing sensory innervation to the skin of the upper eyelid and the bridge of the nose.^[2]

Structure

The infratrochlear nerve is a mixed nerve, meaning that it contains both sensory and motor fibers. It arises from the ophthalmic nerve and travels through the orbital cavity, passing through the infratrochlear canal, which is a small bony canal located within the frontal bone above the orbit.^[4]

Location

The infratrochlear nerve is located in the orbital cavity, which is the bony structure that surrounds the eye.^[3] It passes through the infratrochlear canal and innervates the skin of the upper eyelid and the bridge of the nose.

Function

The main function of the infratrochlear nerve is to provide sensory innervation to the skin of the upper eyelid and the bridge of the nose.^[1]It is responsible for transmitting sensory information, such as touch, temperature, and pain, from these areas to the brain.^[6]

Clinical significance

Damage to the infratrochlear nerve can result in numbness or decreased sensation in the skin of the upper eyelid and the bridge of the nose.^[5] This can be caused by trauma, surgery, or other conditions that affect the trigeminal nerve or the ophthalmic nerve.^[8] In addition, the infratrochlear nerve can be affected by certain conditions, such as orbital cellulitis, which is an infection of the tissues surrounding the eye. This can cause inflammation and swelling, which can compress the infratrochlear nerve and result in decreased sensation in the affected areas.^[7]