Fissures, foramina and markings of the base of the skull

Author: Scott A. Sheffield MS

Last update:

The base of the skull (base of cranium) includes openings for the transmission of blood vessels and nerves as well as several fissures and other notable markings.

Ethmoid bone:

  1. (lamina cribrosa ethmoidalis).
  2. image descriptionCrista galli (crista galli ethmoidalis).
Cranial Floor
Cribriform plate - Cranial Floor
Cribriform plate - Cranial Floor - Colored
Crista galli - Cranial Floor
Crista galli - Cranial Floor - Colored
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Quickly and efficiently learn the bones of the body with these interactive skeletal system quizzes and diagrams!

Frontal bone:

  1. image descriptionOrbital part (pars orbitalis frontalis).
  2. image descriptionOrbital surface or plate (facies orbitalis frontalis).
Cranial Floor
Orbital part - Cranial Floor
Orbital part - Cranial Floor - Colored
Orbital surface - Cranial Floor
Orbital surface - Cranial Floor - Colored
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Sphenoid bone:

  1. image descriptionBody (corpus sphenoidale).
  2. image descriptionLesser wing (ala minor sphenoidale).
  3. image descriptionOptic canal (canalis opticus sphenoidale).
  4. image descriptionChiasmatic groove or prechiasmatic sulcus (sulcus chiasmaticus or sulcus prechiasmaticus sphenoidale).
Cranial Floor
Body - Cranial Floor
Anterior clinoid process - Cranial Floor
Lesser wing - Cranial Floor
Lesser wing - Cranial Floor - Colored
Optic canal - Cranial Floor
Optic canal - Cranial Floor - Colored
Chiasmatic groove - Cranial Floor
Chiasmatic groove - Cranial Floor - Colored
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  1. image descriptionAnterior clinoid process (anterior clinoid process sphenoidale).
  2. image descriptionGreater wing (ala major sphenoidale).
  3. image descriptionForamen ovale (foramen ovale sphenoidale).
  4. image descriptionForamen spinosum (foramen spinosum sphenoidale).
Cranial Floor
Anterior clinoid process - Cranial Floor
Anterior clinoid process - Cranial Floor - Colored
Greater wing - Cranial Floor
Greater wing - Cranial Floor - Colored
Foramen ovale - Cranial Floor
Foramen ovale - Cranial Floor - Colored
Foramen spinosum - Cranial Floor
Foramen spinosum - Cranial Floor - Colored
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  1. image descriptionForamen rotundum (foramen rotundum sphenoidale).
  2. image descriptionSella Turcica (sella turcica sphenoidale).
  3. image descriptionHypophyseal fossa (fossa hypophysialis sphenoidale).
  4. image descriptionTuberculum sellae (tuberculum sellae sphenoidale).
Cranial Floor
Foramen rotundum - Cranial Floor
Foramen rotundum - Cranial Floor - Colored
Sella turcica - Cranial Floor
Sella turcica - Cranial Floor - Colored
Hypophyseal fossa - Cranial Floor
Hypophyseal fossa - Cranial Floor - Colored
Tuberculum sellae - Cranial Floor
Tuberculum sellae - Cranial Floor - Colored
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  1. image descriptionDorsum sallae (dorsum sallae sphenoidale).
  2. image descriptionPosterior clinoid process (processus clinoideus posterior sphenoidale).
Cranial Floor
Dorsum sallae - Cranial Floor
Dorsum sallae - Cranial Floor - Colored
Posterior clinoid process - Cranial Floor
Posterior clinoid process - Cranial Floor - Colored
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Temporal bone:

  1. image descriptionSquamous part or temporal squama (pars squamosa; squama temporalis).
  2. image descriptionPetrous part (pars petrosa temporalis).
  3. image descriptionInternal acoustic meatus or auditory meatus (meatus acusticus internus temporalis).
Cranial Floor
Squamous part - Cranial Floor
Squamous part - Cranial Floor - Colored
Petrous part - Cranial Floor - Colored
Petrous part - Cranial Floor - Colored
Internal accoustic meatus - Cranial Floor
Internal accoustic meatus - Cranial Floor - Colored
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Occipital bone:

  1. image descriptionForamen magnum  (foramen magnum occipitalis).
  2. image descriptionHypoglossal canal (canalis nervi hypoglossi temporalis).
  3. image descriptionCruciform eminence (eminentia cruciformis temporalis).
  4. image descriptionInternal occipital protuberance (protuberantia occipitalis interna).
Cranial Floor
Foramen magnum - Cranial Floor
Foramen magnum - Cranial Floor - Colored
Hypoglossal canal - Cranial Floor
Hypoglossal canal - Cranial Floor - Colored
Cruciform eminence - Cranial Floor
Cruciform eminence - Cranial Floor - Colored
Internal occipital protuberance - Cranial Floor
Internal occipital protuberance - Cranial Floor - Colored
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Need a speedier way to learn and memorize? Look no further than these interactive skull quizzes, diagrams and worksheets.

  1. (crista occipitalis interna).
  2. (sulcus sinus transversi occipitalis).
Cranial Floor
Internal occipital crest - Cranial Floor
Internal occipital crest - Cranial Floor - Colored
Groove for transverse sinus - Cranial Floor
Groove for transverse sinus - Cranial Floor - Colored
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Between bones:

  1. image descriptionForamen lacerum (foramen lacerum).
  2. image descriptionJugular foramen (foramen jugulare).
Cranial Floor
Foramen lacerum - Cranial Floor - Colored
Foramen lacerum - Cranial Floor - Colored
Jugular foramen - Cranial Floor
Jugular foramen - Cranial Floor - Colored
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Multiple bones involved:

  1. image descriptionGroove for sigmoid sinus (sulcus sinus sigmoidei).
  2. image descriptionAnterior cranial fossa (fossa cranii anterior).
  3. image descriptionMiddle cranial fossa (fossa cranii media).
  4. image descriptionPosterior cranial fossa (fossa cranii posterior).
Cranial Floor
Groove for sigmoid sinus - Cranial Floor
Groove for sigmoid sinus - Cranial Floor - Colored
Anterior cranial fossa - Cranial Floor
Anterior cranial fossa - Cranial Floor - Colored
Middle cranial fossa - Cranial Floor
Middle cranial fossa - Cranial Floor - Colored
Posterior cranial fossa - Cranial Floor
Posterior cranial fossa - Cranial Floor - Colored
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Test yourself:

Part[1]: [image descriptionShow/image descriptionHide]
Part[2]: [image descriptionShow/image descriptionHide]
Part[3]: [image descriptionShow/image descriptionHide]
Part[4]: [image descriptionShow/image descriptionHide]

Cranial Floor - Test yourself - Part1
Cranial Floor - Test yourself - Part1 - Answers
Cranial Floor - Test yourself - Part2
Cranial Floor - Test yourself - Part2 - Answers
Cranial Floor - Test yourself - Part1
Cranial Floor - Test yourself - Part1 - Answers
Cranial Floor - Test yourself - Part2
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Enhance your knowledge even more with these quizzes:

Cranial Floor Skull Bone Markings Quiz 1

Cranial Floor Skull Bone Markings Quiz 2