Basis Cranii Interna

The cranial base's internal surface is subdivided into three large fossas — anterior, middle, and posterior — to support the brain's frontal lobe, temporal lobe, and the brain stem with the cerebellum, respectively.

Icon of crossfade image Basis cranii interna, or internal surface of the skull base with the latin tetminology markup
Basis cranii interna, or internal surface of the skull base
Internal surface of the base of the skull. Top view. Calvaria is removed.
The image demonstrates cerebral surfaces of bones of the skull that forms the anterior, middle, and posterior cranial fossas.
The list of terms: Fossa cranii anterior – Anterioir cranial fossa
Squama frontalis – Squama of frontal bone
Pars orbitalis ossis frontalis – Orbital part of the frontal bone
Lamina cribrosa ossis ethmoidalis – Cribriiform plate of ethmoid bone
Ala minor ossis sphenoidalis – Lesser wing of sphenoid bone
Sulcus prechiasmaticus – Chiasmatic groove
Fossa cranii media – Middle cranial fossa
Corpus ossis sphenoidalis – Body of sphenoid bone
Ala major ossis sphenoidalis – Greater wing of sphenoid bone
Pars squamosa ossis temporalis – Squamous part of temporal bone
Facies anterior partis petrosae – Anterior surface of the petrous part of temporal bone
Sulcus sinus petrosi superioris – Groove for superior petrosal sinus
Angulus mastoideus ossis parietalis – Mastoid angle of parietal bone
Fossa cranii posterior – Posterior cranial fossa
Facies posterior partis petrosae – Posterior surface of petrous part
Processus mastoideus – Mastoid process
Dorsum sellae
Clivus
Pars lateralis ossis occipitalis – Lateral part of occipital bone
Squama occipitalis – Squama of occipital bone
Icon of crossfade image Latin terminology comments for inner surface of the base of skull
Structures and communications to the internal surface of the cranial base
The detailed view of the cranial base's inner surface with emphasis on openings and connections to other topographical areas of the skull. Note the yellowish hue of the central part of the temporal pyramid caused by the osseous labyrinth's solid compact bone.
The list of terms: Sinus frontalis – Frontal sinus
Fossa cranii anterior – Anterior cranial fossa
Crista frontalis – Frontal crest
Foramen caecum
Crista galli
Foramen ethmoidale anterius – Anterior ethmoid foramen
Foramina cribrosa – Cribriform foramina
Impressiones digitatae – Digitate impressions
Juga cerebralia – Cerebral ridges of cranium
Processus clinoideus anterior – Anterior clinoid process
Fossa cranii media – Middle cranial fossa
Sulcus prechiasmaticus – Chiasmatic groove
Sella turcica – Turkish saddle
Tuberculum sellae
Fossa hypophysialis – Hypophysial fossa
Dorsum sellae
Processus clinoideus posterior – Posterior clinoid process
Sulcus caroticus – Carotid sulcus
Foramen rotundum – Round foramen
Foramen ovale – Oval foramen
Foramen spinosum – Spinous foramen
Foramen lacerum
Impressio trigeminalis – Trigeminal impression
Tegmen tympani – Roof of tympanic cavity
Eminentia arcuata – Arcuate eminence
Sulcus sinus petrosi superioris – Groove for superior petrosal sinus
Fossa cranii posterior – Posterior cranial fossa
Clivus
Sulcus sinus petrosi inferioris – Groove for inferior petrosal sinus
Sulcus sinus transversi – Groove for transverse sinus
Sulcus sinus sigmoidei – Groove for sigmoid sinus
Foramen mastoideum – Mastoid foramen
Fossa cerebellaris – Cerebellar fossa
Crista occipitalis interna – Internal occipital crest
Protuberantia occipitalis interna – Internal occipital protuberance
Foramen magnum
Icon of crossfade image The canals of the posterior fossa of the cranial base
Cranial base. Oblique and slightly dorsal view
Some important structures like jugular foramen and internal acoustic meatus could be seen only from the skull's dorsal aspect. Note also the optic canal position relative to the border between the anterior and middle cranial fossa.
The list of terms: Canalis opticus – Optic canal
Sulcus sinus petrosi inferioris – Groove for inferior petrosal sinus
Porus et meatus acusticus internus – Internal auditory porus & meatus
Apertura externa aqueductus vestibuli – External opening of vestibular aqueduct
Sulcus sinus sigmoidei – Groove for sigmoid sinus
Fissura orbitalis superior – Superior orbital fissure
Foramen rotundum – Round foramen
Foramen jugulare – Jugular foramen
Canalis hypoglossalis – Hypoglossal canal
First published: Feb/2020
Last update: 14/Oct/2021