Base of skull
Under the skull base ( base of the skull Latin ) refers to the lower part of the skull. It is made up of units of the frontal bone ( frontal ), the ethmoid bone ( ethmoid bone ), the sphenoid ( sphenoid ) of the temporal bone ( temporal bone ) and the occipital bone ( occipital bone ). In animal anatomy not include frontal and ethmoid to the skull base, as these there not as the lower ( basal ) portions of the skull are considered.
The inner skull base (base of the skull interna), that is the bottom of the brain containing the cranial cavity is divided into:
- Anterior cranial fossa ( fossa anterior cranial fossa in animals rostralis )
- Middle cranial fossa ( fossa media) and
- Posterior cranial fossa ( posterior fossa, in animals fossa caudalis ).
Openings
In the area of the skull base, there are a number of openings for the passage of cranial nerves and blood vessels:
- Optic canal: optic nerve, ophthalmic artery
- Hypoglossal canal: the hypoglossal nerve
- Jugular foramen: Vagusgruppe, internal jugular vein
- Canalis musculotubarius: eustachian tube
- Carotid canal (only in humans and predators ): internal carotid artery
- Foramen rotundum: maxillary nerve
- Foramen ovale ( in humans, carnivores, ruminants): mandibular nerve
- Foramen spinosum (humans, predators ): middle meningeal artery
- Foramen lacerum (humans, horses, pigs )
- Internal acoustic meatus, internal opening of the internal auditory meatus ( Internal Auditory Canal ): vestibulocochlear nerve, facial nerve
- Foramen Alare caudal (dogs, horses): maxillary artery