CRANIUMCRANIUM

THE SKULLTHE SKULL

R. DrugaR. DrugaInstitute of Anatomy, 2nd and 1st Medical Institute of Anatomy, 2nd and 1st Medical

FacultyFaculty

NEUROCRANIUM NEUROCRANIUM

SPLANCHNOCRANIUMSPLANCHNOCRANIUM

CRANIUM, THE SKULL ICRANIUM, THE SKULL I Most highly modified region in the axial Most highly modified region in the axial

skeletonskeleton

The neurocraniumThe neurocranium – developed from a – developed from a series of cartilages ventral to the brain (base)series of cartilages ventral to the brain (base)

From mesenchyme over the dome of the From mesenchyme over the dome of the head (calvaria or calva)head (calvaria or calva)

Cranial cavityCranial cavity

Splanchnocranium Splanchnocranium – branchial apparatus – branchial apparatus (cartilaginous elements) have been replaced (cartilaginous elements) have been replaced by overlying dermal bonesby overlying dermal bones

Branchial apparatusBranchial apparatus

The mandibular region and the neck are The mandibular region and the neck are formed by six paired branchial arches formed by six paired branchial arches (cart. bars supporting the gill apparatus).(cart. bars supporting the gill apparatus).

In the tetrapods branchial arches were In the tetrapods branchial arches were modified and persist in the facial (maxilla, modified and persist in the facial (maxilla, mandibula) and neck skeleton (laryngeal mandibula) and neck skeleton (laryngeal cartilages)cartilages)

Derivatives of cartilagines of the branchial arches

1st arch = Meckel cart., mandibula, malleus

2nd arch = Reichert cart., stapes, styloid proc.,stylohyoid lig.

3rd arch = hyoid bone

4th and 6th arch = laryngeal cartil.

CRANIUM IICRANIUM II

Complex of skeletal elements, adapted to Complex of skeletal elements, adapted to support and contain the brain, brain vessels, support and contain the brain, brain vessels, cranial nerves and envelopscranial nerves and envelops

Special senses (eye ball, nasal cavity, inner ear)Special senses (eye ball, nasal cavity, inner ear) Intracranial spaces (epidural, subdural, Intracranial spaces (epidural, subdural,

subarachnoideal)subarachnoideal) Circulating cerebrospinal fluidCirculating cerebrospinal fluid xx

CRANIUMCRANIUM

Komplex kostí axiálního skeletuKomplex kostí axiálního skeletu Obsahuje mozek, mozkové cévy a obalyObsahuje mozek, mozkové cévy a obaly Obsahuje oční kouli a sluchový aparátObsahuje oční kouli a sluchový aparát Člení se na bazi lební, kalvu Člení se na bazi lební, kalvu

(calvaria) a na obličejový skelet.(calvaria) a na obličejový skelet. Pro klinickou medicinu má největší Pro klinickou medicinu má největší

význam baze lební a obličejový význam baze lební a obličejový skelet !!skelet !!

CRANIUM IIICRANIUM III

General cranial featuresGeneral cranial features Base Base CalvariaCalvaria Facial skeletonFacial skeleton Spaces, cavitiesSpaces, cavities The skull, considered as a whole, is of greater The skull, considered as a whole, is of greater

practical importance than the individual bones of practical importance than the individual bones of which it is made up !!!!!! Most important part of which it is made up !!!!!! Most important part of the skull is the the skull is the base.base.

Norma lateralis

Norma facialis

orNorma frontalis

The orbit

The anterior nasal aperture

The interior of the cranium

Basis cranii interna

Norma basalis

Basis cranii externa

The anterior, middle and posterior cranial fossa

Basis cranii interna

Fossae cranii

!

OS OCCIPITALE

Squamous, basilar and lateral part

Internal aspect Cruciate eminence, 4 fossae

Occipital bone of a newborn child

Posterior aspect

Inferior aspect

OS SPHENOIDALE

In the base of the skull

Resembles a bird with wings outstretched

Body

The greater wings

The lesser wings

The pterygoid processes

Posterior aspect

Superior aspect

Chiasmatic sulcus – optic cana

Hypophyseal fossa

Dorsum sellae

Sella turcicaSulcus caroticus

Sphenoid bone – bodySphenoid bone – body

Cubical, contains two air sinuses / Cubical, contains two air sinuses / septumseptum

Anteriorly – ethmoid boneAnteriorly – ethmoid bone Posteriorly – occipital bonePosteriorly – occipital bone Sulcus chiasmatis (optic canal)Sulcus chiasmatis (optic canal) Hypophyseal fossa + Dorsum sellae= Hypophyseal fossa + Dorsum sellae=

sella turcica (Turkish saddle)sella turcica (Turkish saddle)

Fissura orbitalis superior :

III., IV., VI., V/1,

V. orbitalis sup.

For. rotundum : V/2

For. ovale : V/3

For. spinosum: a. meningea media

ANTERIOR ASPECT

Greater wing – 5 surfaces (facies)Greater wing – 5 surfaces (facies)

Cerebral surfaceCerebral surface – part of the midle cranial fossa – part of the midle cranial fossa Orbital surfaceOrbital surface – part of the lateral wall of the orbit – part of the lateral wall of the orbit Temporal surface – Temporal surface – temporal fossatemporal fossa Infratemporal surface- Infratemporal surface- infratemporal fossainfratemporal fossa Sphenomaxillar surface- Sphenomaxillar surface- pterygopalatine fossapterygopalatine fossa

OS TEMPORALE

Parts: Squamous

Petromastoid

Tympanic

(styloid process)

Petrous part of the temporal bonePetrous part of the temporal bone

Is wedged between the sphenoid and occipital Is wedged between the sphenoid and occipital bonesbones

Has a base, an apex, four surfaces, three marginsHas a base, an apex, four surfaces, three margins The anterior (superior) surface (The anterior (superior) surface (trigeminal impression, trigeminal impression,

arcuate eminence)arcuate eminence) The posterior surface The posterior surface (the internal acoustic meatus)(the internal acoustic meatus) The inferior surface (The inferior surface (the carotid canal, the jugular fossa)the carotid canal, the jugular fossa) The ventrobasal surface (The ventrobasal surface (medial wall of the tympanic medial wall of the tympanic

cavity)cavity)

xx

OS TEMPORALE – PARS PETROSA, OS TEMPORALE – PARS PETROSA, PYRAMISPYRAMIS

Klínovitá konfigurace- mezi os sphenoidale a Klínovitá konfigurace- mezi os sphenoidale a occipitaleoccipitale

Base, apex, 4 stěny (facies)Base, apex, 4 stěny (facies) Facies posterior (porus acusticus internus)Facies posterior (porus acusticus internus) Facies inferior (canalis caroticus, fossa jugularis)Facies inferior (canalis caroticus, fossa jugularis) Facies anterior (eminentia arcuata, impressio Facies anterior (eminentia arcuata, impressio

trigeminalis)trigeminalis) Facies ventrobasalis (= mediální stěna cavum Facies ventrobasalis (= mediální stěna cavum

tympani)tympani)

Temporal bone + pyramis – external aspect

PYRAMIS-internal

aspect (facies ant. et post.)

Internal acoustic meatus - n. VII., n.VIII.)

Porus and meatus acusticus internus

Meatus acusticus internus l. dx.

PYRAMIS,

FACIES INFERIOR

Stylomastoid foramen (n. VII.)

Jugular foramen

(internal jugular vein, N. IX., X., XI.)

Canaliculus for the tympanic nerve

Carotid canal

Jugular foramen

Facies inferior

Canalis caroticus

Foramen jugulare

Processus styloideus

Foramen Stylomastoideum

Processus mastoideus

Fossa mandibularis

Canaliculus tympanicus

PYRAMIS : FACIES VENTROBASALIS

Medial wall of the tympanic cavity

Stylomastoid foramen.

Mastoid air cells

Celullae mastoideae

Pneumatic type

Canalis n. facialis

Tympanic cavity

Promontory

Tympanic nerve –

Tympanic plexus

Tympanic cavity, posterior wall

Mastoid antrum (3,5)

External auditory meatus (1)

N. VII.

Pyramidal eminenceChorda tympani

Tympanic sulcus

Pyramid - canals and spacesPyramid - canals and spaces

Canalis nervi facialisCanalis nervi facialis – – meatus ac. internus – for. meatus ac. internus – for. Stylomastoideum (3 parts :ventrolateral, dorsolateral, caudal)Stylomastoideum (3 parts :ventrolateral, dorsolateral, caudal)

Canalis caroticusCanalis caroticus – – facies inferior – apex pyramidisfacies inferior – apex pyramidis

Canaliculus tympanicusCanaliculus tympanicus – – fossula petrosa – cavum tympani –fossula petrosa – cavum tympani –sulcus promontoriisulcus promontorii

Canaliculus chordae tympani – Canaliculus chordae tympani – canalis n. facialiscanalis n. facialis – – cavum tympani – fissura petrotympanicacavum tympani – fissura petrotympanica

Canalis musculotubariusCanalis musculotubarius – – m. tensor tympani, Eustachian tubem. tensor tympani, Eustachian tube

Labyrinthus osseusLabyrinthus osseus – vestibulum, canales semicirculares, cochlea – vestibulum, canales semicirculares, cochlea

OS FRONTALE, SQUAMA FRONTALIS, PARTES ORBITALES

Desmogenní osifikace ze dvou základů

Inferior aspect

OS FRONTALE, PARTES ORBITALES, PARS NASALIS (Apertura sinus frontalis)

Roof of the orbit

Internal aspect SQUAMA FRONTALIS

OS ETHMOIDALEOS ETHMOIDALE

Lamina cribrosa (nerve I.)Lamina cribrosa (nerve I.) Lamina perpendicularis (crista galli)Lamina perpendicularis (crista galli) Labyrithi ethmoidales (cellulae Labyrithi ethmoidales (cellulae

ethmoidales)ethmoidales) Lamina orbitalis (papyracea)Lamina orbitalis (papyracea) Concha nasalis media et superiorConcha nasalis media et superior

Cock´ s comb

Parietal bone

Sulci of the middle meningeal artery

Epidural space

Epidural hematoma

OBLIČEJOVÝ

SKELET

FACIAL SKELETON

Maxilla

Tělo + 4 výběžky:

Body + 4 processes(proc. frontalis, palatinus, zygomaticus (/apex), alveolaris)

Maxillary sinus (25 cm3)

4 plochy

4 surfaces

Facies :

anterior,

posterior,

orbitalis

nasalis (the base of the hollow pyramidal body)

Maxillary hiatus is ovelaid by ethmoid conchae

Maxilla - ossificationMaxilla - ossification

The maxilla ossifies in membrane.The maxilla ossifies in membrane. The premaxilla (incisive bone, carrying incisor The premaxilla (incisive bone, carrying incisor

teeth) is in most mammals an independent teeth) is in most mammals an independent bone.bone.

OSSA PALATINAOSSA PALATINA

Orbital process (3)

Sphenoidal process (5)

Sphenopalatine incisure

MANDIBULA

CORPUS +

RAMUS –Condylar process (articular surface)

Coronoid process (temporalis m.)

Corpus – Alveolar process

Each half ossifies from a single centre in membrane ovelying the Meckel cartilage

Sublingual fossa

Submandibular fossa

Mandibular canal

Age changes in the mandible

Following the loss of teeth the alveolar part is absorbed

Ramus in line with the body

THE NASAL CAVITY

CAVITAS NASI OSSEA

Piriform aperture –

Choanae

THE ORBITAL CAVITY

ORBITA

Facies lateralis

CAVUM NASI

THE NASAL CAVITY, FRONTAL SECTION

CAVUM NASI

MEATUS NASI :

inferior

medius

superior

SINUSPARANASALES

FrontalMaxillaryEthmoidalSphenoidal

THE ORBIT ORBITA

THE ORBIT, MEDIAL WALL

ORBITA, FACIES MEDIALIS

FOSSA TEMPORALIS,

INFRATEMPORALIS

Temporal fossa

Infratemporal fossa

Infratemporal fossa :Lamina lateralis proc. Pterygoidei and maxilla – mandibular ramus

Pterygomandibular fissure

FOSSA

PTERYGOPALATINA Pterygomandibular fissura

Upper wall : maxillary surface of the greater wings

Medial wall: palatine bone

Anterior wall : maxilla

Posterior wall : pterygoid process

Rotundum

Pterygoid canal

Sphenopalatine for.

Inferior orbital fissure

Greater palatine canal

FOSSAE

CRANII

Anterior

Middle

Posterior

Skull in a new-born

Facial part small (rudimentary condition of the mandible and maxillae)

Ossification is incomplete

Paranasal sinuses - absent

6 fontanellaeLebka Lebka novorozence

Anterior fontanelle

BREGMA

Posterior fontanelle

The skull during the birthThe skull during the birth

The skull is altered in shapeThe skull is altered in shape The skull is compressed and elongatedThe skull is compressed and elongated Bones of cranial vault (calva) overlap to a Bones of cranial vault (calva) overlap to a

small extent (fontanellae !!)small extent (fontanellae !!) These changes disappear within a weekThese changes disappear within a week

xx

Konfigurace lebky při poroduKonfigurace lebky při porodu

Lebka je komprimována (mediolaterálně)Lebka je komprimována (mediolaterálně) Elongace lebkyElongace lebky Kosti kalvy se podsouvají (fontanely)Kosti kalvy se podsouvají (fontanely) V průběhu několika dnů se konfigurace V průběhu několika dnů se konfigurace

lebky vrací k nornálulebky vrací k nornálu

Frankfurt plane

Frankfurtská horizontála

CRANIOMETRY

gnathion

CRANIOMETRY ICRANIOMETRY I

Cranial height = bregma – basion = Výška lebkyCranial height = bregma – basion = Výška lebky

Cranial breadth = euryon – euryon = Šířka lebkyCranial breadth = euryon – euryon = Šířka lebky

Cranial length = glabella - occipital point = Délka lebkyCranial length = glabella - occipital point = Délka lebky

Facial height = nasion – gnathion = Výška obličejeFacial height = nasion – gnathion = Výška obličeje

Facial breadth = zygion - zygion = Šířka obličejeFacial breadth = zygion - zygion = Šířka obličeje

CRANIOMETRY

CRANIAL INDEXŠ x 100/ ddo 75 dolicho-

75 – 80 meso-

80 a více brachy -Breadth x 100/ length

Up to 75 dolichocephalic

75 – 80 mesocephalic

80 – 85

brachycephalic

Sexual differencesFemale : wall thinner, superciliary arches, tuberosities and mastoid processes less prominent, air sinuses smaller, tubera frontalia at parietalia +

References :References :

R. Čihák : Anatomie 1, AvicenumR. Čihák : Anatomie 1, Avicenum M. Grim, R. Druga et al.: Základy anatomie. Galen 2001M. Grim, R. Druga et al.: Základy anatomie. Galen 2001 Gray ´s Anatomy, Longman 1973Gray ´s Anatomy, Longman 1973 P. Kopf – Maier : Atlas of Human Anatomy, Karger, 1990P. Kopf – Maier : Atlas of Human Anatomy, Karger, 1990

KONEC LEBKY