Topics

Topic

design image
Auriculotemporal nerve

The auriculotemporal nerve is a sensory branch of the mandibular division of the trigeminal nerve (CN V3), playing a key role in transmitting sensory information from the temporal region of the scalp, the auricle, external acoustic meatus, tympanic membrane, and the temporomandibular joint (TMJ). It also carries autonomic fibers to the parotid gland via the otic ganglion. Owing to its anatomical course and relationships with adjacent structures, it is of particular interest in radiology and neuroanatomy, especially when evaluating for neuralgia, trauma, or neoplastic involvement.

Synonyms

  • N. auriculotemporalis

  • Auriculo-temporal nerve

  • Branch of CN V3 (Mandibular division of trigeminal nerve)

MRI Appearance

  • PD (Proton Density) Sequence:

    • The auriculotemporal nerve is typically visualized as a thin, linear, low-signal-intensity structure, most easily seen when surrounded by higher-signal fat or soft tissue.

    • It courses adjacent to the superficial temporal vessels and near the TMJ, sometimes seen between the temporalis muscle and the parotid gland.

  • STIR (Short Tau Inversion Recovery) Sequence:

    • The nerve maintains a low signal on STIR, similar to other peripheral nerves.

    • Pathological states (neuritis, edema, trauma) may cause increased signal intensity, resulting in the nerve appearing hyperintense compared to the normal state.

  • T1-Weighted Sequence:

    • On T1-weighted images, the auriculotemporal nerve appears as a small, linear, hypointense structure compared to the surrounding hyperintense fat.

    • Its identification is enhanced by its proximity to anatomical landmarks like the TMJ and the superficial temporal artery.

MRI images

Auriculotemporal nerve mri image