Hypoglossal canal
Exit foramen · CN XII
A canal in the occipital bone above the occipital condyle, anteromedial to the jugular foramen, carrying the hypoglossal nerve from the posterior cranial fossa into the upper neck along with a meningeal branch of the ascending pharyngeal artery and an emissary vein.
Traced from the start
- Medulla oblongata
- Hypoglossal nerve (CN XII)
- Hypoglossal canal
Detail
- Transmits
- Hypoglossal nerve (XII), meningeal branch of the ascending pharyngeal artery, emissary vein linking the basilar venous plexus to the internal jugular vein
- Bone
- Occipital, immediately above the condyle; the condyle can fracture into the canal
When it goes wrong
Occipital condyle fracture, clival chordoma, skull base metastasis or nasopharyngeal carcinoma involving the canal
Isolated lower motor neurone hypoglossal palsy with tongue deviation towards the lesion, wasting and fasciculation; with adjacent jugular foramen involvement it becomes Collet–Sicard syndrome
Practise this structure
4 questions in the bank tagged Cranial Nerves.
A 52-year-old woman has had two months of numbness over the right forehead, the right upper eyelid and the tip of her nose, with a gritty feeling in the right e…
Foundations · middle twist
A 44-year-old man has had 18 months of worsening hearing on the left with constant ringing in that ear. He still follows conversation in a quiet room but cannot…
Foundations · middle twist
A 58-year-old man has sudden vertigo and a hoarse voice, and chokes when he drinks. The palate elevates to the right and there is no gag response when the left…
Foundations · middle twist
A 27-year-old man was struck on the head at football a week ago. He now sees two images, one above the other, worst when reading or going down stairs. The verti…
Foundations · middle twist