Corpus: Foramen lacerum

The foramen lacerum (German: "torn hole") is an irregularly shaped bone opening at the base of the skull in the area of the middle cranial fossa.

The foramen lacerum is located where the occipital bone, sphenoid bone and temporal bone meet. It lies anteromedial to the carotid canal and is formed by the following bone structures:

• posteriorly from the pars petrosa ossis temporalis (temporal bone),
• anteriorly from the posterior edge of the large wing of the sphenoid bone,
• medially from the petrosal process of the sphenoid bone and a small bone portion of the occipital bone

In vivo, the foramen lacerum is closed by fibrous cartilage through which the following anatomical structures pass:

• Arteria canalis pterygoidei
• Ramus meningealis of the ascending pharyngeal artery
• canalic pterygoid nerve
  • Greater petrosal nerve
  • Profundus petrosus nerve
• Minor petrosal nerve
• Minor emissary veins

Some of the structures run from the foramen lacerum into the pterygoid canal, others into the infratemporal fossa.

The internal carotid artery lies on the foramen lacerum. The part of the artery above the foramen is also known as the "lacerum segment".

Nasopharyngeal carcinomas can gain access to the cavernous sinus via the foramen lacerum and arrode cranial nerves.