Infratrochlear nerve
| Infratrochlear nerve | |
|---|---|
Sensory innervation of the head. The infratrochlear nerve is seen in the green area, emerging from the orbit. | |
| Details | |
| From | Nasociliary nerve |
| Innervates | Skin of eyelids, conjunctiva, lacrimal sac, lacrimal caruncle, side of nose above medial canthus |
| Identifiers | |
| Latin | nervus infratrochlearis |
| TA98 | A14.2.01.035 |
| TA2 | 6214 |
| FMA | 52693 |
| Anatomical terms of neuroanatomy | |
The infratrochlear nerve is a sensory branch of the nasociliary nerve (itself a branch of the ophthalmic nerve (CN V1)) in the orbit.[1] It courses along the medial wall of the orbit and exits near the medial angle of the eye beneath to the trochlea of superior oblique.[2] It provides sensory innervation to structures at the medial orbit including the skin of the medial eyelids, root of the nose, and parts of the lacrimal sac.[1]: 631, 783 This nerve is relevant in procedures involving the medial eyelid, lacrimal apparatus, and nasal root.[3]
Structure
The nasociliary nerve terminates by bifurcating into the infratrochlear and the anterior ethmoidal nerves. The infratrochlear nerve travels anteriorly in the orbit along the upper border of the medial rectus muscle and underneath the trochlea of the superior oblique muscle. It exits the orbit medially and divides into small sensory branches.[4]
Distribution
The infratrochlear nerve provides sensory innervation to the skin of the eyelids, the conjunctiva, lacrimal sac, lacrimal caruncle, and the side of the nose superior to the medial canthus.[1]: 631, 783
Communications
The infratrochlear nerve receives a descending communicating branch from the supratrochlear nerve.[1]: 782
Etymology
The infratrochlear nerve is named after a structure it passes under. Infratrochlear means "below the trochlea". The term trochlea means "pulley" in Latin. Specifically, the trochlea refers to a fibrocartilaginous loop at the superomedial surface of the orbit called the trochlea, through which the tendon of the superior oblique muscle passes.[1]
Additional images
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Nerves of the orbit. Seen from above. The infratrochlear nerve is labelled at the top left, and can be seen as a terminal branch of the nasociliary nerve, along with the anterior ethmoidal nerve.
References
- ^ a b c d e Standring, Susan (2020). Gray's Anatomy: The Anatomical Basis of Clinical Practice (42th ed.). New York. p. 631. ISBN 978-0-7020-7707-4. OCLC 1201341621.
{{cite book}}: CS1 maint: location missing publisher (link) - ^ Lieber, Stefan; Fernandez-Miranda, Juan C. (August 2020). "Anatomy of the Orbit". Journal of Neurological Surgery Part B: Skull Base. 81 (04): 319–332. doi:10.1055/s-0040-1715096. ISSN 2193-6331. PMC 7561454. PMID 33072474.
- ^ "Sage Journals: Discover world-class research". Sage Journals. March 18, 2015. doi:10.1177/0333102415578429. Retrieved 2026-03-10.
- ^ Gray's anatomy : the anatomical basis of clinical practice. Standring, Susan (41 ed.). [Philadelphia]. 2016. ISBN 978-0-7020-5230-9. OCLC 920806541.
{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
External links
- MedEd at Loyola GrossAnatomy/h_n/cn/cn1/cnb1.htm
- cranialnerves at The Anatomy Lesson by Wesley Norman (Georgetown University) (V)
