Hypoglossal canal

Last revised by Henry Knipe on 30 Jan 2024

Citation, DOI, disclosures and article data

Citation:

Gaillard F, Knipe H, Worsley C, et al. Hypoglossal canal. Reference article, Radiopaedia.org (Accessed on 23 Apr 2024) https://doi.org/10.53347/rID-1481

DOI:

https://doi.org/10.53347/rID-1481

Permalink:

https://radiopaedia.org/articles/1481

rID:

1481

Article created:

2 May 2008, Frank Gaillard ◉ ◈

Disclosures:

At the time the article was created Frank Gaillard had no recorded disclosures.

View Frank Gaillard's current disclosures

Last revised:

30 Jan 2024, Henry Knipe ◉ ◈

Disclosures:

At the time the article was last revised Henry Knipe had the following disclosures:

Integral Diagnostics, Shareholder (ongoing)
Micro-X Ltd, Shareholder (ongoing)

These were assessed during peer review and were determined to not be relevant to the changes that were made.

View Henry Knipe's current disclosures

Revisions:

14 times, by 8 contributors - see full revision history and disclosures

Systems:

Head & Neck

Sections:

Anatomy

The hypoglossal canal is located between the occipital condyle and jugular tubercle and runs obliquely forwards (posteromedial to anterolateral) allowing the hypoglossal nerve to exit the posterior cranial fossa.

Its proximal portion is often divided by a fibrous (sometimes ossified) septum, which separates the two roots of the hypoglossal nerve (these have formed by the convergence of numerous rootlets). These roots merge within the canal and a single nerve emerges.

In addition to the hypoglossal nerve, the canal also allows a meningeal branch of the ascending pharyngeal artery to enter the skull, and a multiple veins, forming the hypoglossal venous plexus, to exit ⁵.

Radiographic features

The hypoglossal canal is most easily identified on axial or coronal images through the occipital condyles, where it can be seen passing anterolaterally from the posterior fossa into the upper neck.

On coronal imaging, the jugular tubercle appears beak-like extending over the hypoglossal canal. Combined with occipital condyle the coronal appearance is reminiscent of an eagle seen in profile, making this a convenient landmark ^3,4.