Anatomy of the human temporal bone. Temporal bone Carotid canal temporal

The temporal bone (os temporale) is paired; it contains the organs of hearing and balance. Nerves and blood vessels pass through its channels. The bone consists of three parts (Fig. 51).

The scales (squama) have the shape of an oval thin plate located vertically, almost in the sagittal plane. The zygomatic process (processus zygomaticus) begins from the temporal surface of the scales. At the beginning of this process, on the lower surface of the scales, there is a mandibular fossa (fossa mandibularis), in front of which there is an articular tubercle (tuberculum articulare). On the cerebral surface of the scales there are imprints from the middle meningeal artery (a. meningea media) and the convolutions of the temporal lobe of the brain.

51. Right temporal bone.
A - view from the inside: 1 - eminentia arcuata; 2 - tegmen tympani; 3 - pars petrosa; 4 - sulcus sinus sigmoidei; 5 - apertura externa canaliculi cochleae; 6 - processus styloideus; 7 - apertura externa aqueductus vestibuli; 8 - porus acusticus internus; 9 - sulcus sinus petrosi superioris; 10 - processus zygomaticus.
B - bottom view: 1 - processus zygomaticus; 2 - fissura petrosquamosa; 3 - canalis musculotubarius; 4 - for. caroticum externtum; 5 - fossula petrosa; B - apertura externa canaliculi cochleae; 7 - fossa jugularis; 8 - sulcus arteriae occipitalis; 9 - incisura mastoidea; 10 - processus mastoideus; 11 - for. stylomastoideum; 12 - meatus acusticus externus; 13 - fossa mandibularis; 14 - tuberculum articulare.

The tympanic part (pars tympanica) has the shape of a semiring and takes part in the construction of the anterior, lower and posterior walls of the external auditory canal (meatus acusticus externus), the upper wall of which is limited by scales.

The stony part (pyramid) (pars petrosa) is triangular in shape, facing medially and anteriorly, has anterior, posterior and inferior surfaces, anterior, superior and posterior edges.

On the front surface of the stony part, when connecting it to the scales, there is a platform - the roof of the tympanic cavity (tegmen tympani). In front, this area is limited by a fissure (fissura petrosquamosa), and laterally by an arcuate elevation (eminentia arcuata). Below it are the anterior and posterior semicircular canals of the inner ear. From the eminentia arcuata, closer to the apex of the pyramid, there are two openings representing the exit points of the greater and lesser petrosal nerves (hiatus canalis n. petrosi majoris et minoris), opening into the grooves of the same name, which are oriented towards the apex of the pyramid.

On the posterior surface of the petrous part there is an internal auditory opening (porus acusticus internus), where the facial and vestibulocochlear nerves pass. At the base of the stony part there is a deep sigmoid groove (sulcus sigmoideus), into which the opening of the mastoid venous outlet opens. Lateral to the internal auditory canal there is a slit-like opening of the aqueduct of the vestibule of the inner ear (apertura externa aqueductus vestibuli). On the upper edge, between the anterior and posterior surfaces of the stony part, there is a groove (siilcus sinus petrosi superioris), which reaches the sigmoid groove behind and the apex of the pyramid in front.

On the lower surface of the base of the stony part there is a styloid process (processus styloideus); behind it, the stylomastoid foramen (for. stylomastoideum) opens, representing the opening of the facial nerve canal. Medial to the styloid process the jugular fossa (fossa jugularis) is visible, the posterior edge of which has a notch of the same name. The anterior edge of the jugular fossa borders the external opening of the carotid canal (for. caroticum externum). In the anterior edge there is a small stony fossa (fossula petrosa), at the bottom of which the tympanic canal (canaliculus tympanicus) begins. In adults, behind the stylomastoid foramen and the external auditory canal is the mastoid process (processus mastoideus). In its thickness there are cells lined with mucous membrane and communicating with the tympanic cavity. Medial to the mastoid process are the mastoid fissure and the occipital groove. The latter contains the occipital artery. In the middle of the posterior edge of the pyramid there is an external opening of the cochlea's aqueduct (apertura externa canaliculi cochleae).

Temporal bone canals. The carotid canal (canalis caroticus) begins on the lower surface of the pyramid with the external opening of the same name. The channel in the thickness of the pyramid turns at an angle of 90° and goes to the top of the pyramid, where it ends with an internal opening (for. caroticum internum).

The facial canal (canalis facialis) begins in the internal auditory canal, then crosses transversely the pyramid and at the cleft of the greater petrosal nerve (hiatus canalis n. petrosi majoris) turns at a right angle to the side - the knee of the facial canal (geniculum canalis facialis), then goes laterally , located at the junction of the roof of the tympanic cavity with the labyrinthine wall of the inner ear. At the posterior wall of the tympanic cavity, the canal turns and goes down, ending on the lower surface of the pyramid of the temporal bone with a stylomastoid foramen.

The muscular-tubal canal (canalis musculotubarius) is limited by the anterior edge of the apex of the pyramid and the scales. It consists of two sections: the semicanal of the auditory tube (semicanalis tubae auditivae) and the semicanal of the tensor tympani muscle (semicanalis m. tensoris tympani).

The tympanic canaliculus (canaliculus tympanicus) is very narrow; begins in the fossula petrosa and opens on the anterior surface of the petrous part of the pyramid with the cleft of the canal of the lesser petrosal nerve (hiatus canalis n. petrosi minoris).

The canaliculus chordae tympani extends from the facial canal before it exits the petrous part. It opens into the petrotympanic fissure of the mandibular fossa.

Ossification. The temporal bone of a newborn consists of three independent parts, which are described above. The external auditory canal is relatively short and wide. The tympanic cavity is filled with loose connective tissue, which resolves within the first 3 months after birth.

The tympanic part is presented in the form of an incomplete ring located under the scales lateral to the pyramid. The eardrum is stretched in the lumen of the ring. The process of ossification occurs in connective tissue (primary bone), bypassing the cartilaginous stage. By the age of 6 years, the external auditory canal develops from the semiring, scales and mastoid process. At the 8th week of intrauterine development, three ossification points appear in the fibrous connective tissue of the scales. From the back of the scales and the lateral part of the pyramid, under the action of the sternocleidomastoid muscle, the mastoid process is formed, which is pneumatized in three stages: up to 1 year, a tympanic invagination is formed, up to 3 years, cells are formed, and up to 6 years, pneumatization of the process is completely completed. In the cartilaginous base of the pyramid, 5 bone nuclei appear in the fifth month of intrauterine development, which merge at the time of birth.

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(os temporale), steam room. There are three parts located around the external auditory opening: scaly, pyramidal (stony part) and tympanic (Fig. 1, 2).

The organs of hearing and balance are located in the temporal bone; blood vessels and nerves pass through its canals. It is involved in the formation of the temporomandibular joint.

Scaly part(pars squamosa) It is a vertically located plate, connected by its free edge with the lower edge of the parietal bone and with the large wing of the sphenoid bone. Below it is adjacent to the tympanic and petrosal parts and is separated from them tympani-squamous fissure (fissura tympanosquamosa) And stony-scaly fissure (fissura petrosquamosa)[visible only on bones of young subjects].

Outdoor, temporal surface (fades temporalis), the scaly part is smooth, participates in the formation of the temporal fossa. Below it is limited zygomatic process (processus zygomaticus), which is directed anteriorly, connects with the temporal process of the zygomatic bone, forming the zygomatic arch. At the base of the zygomatic process there is a root that forms articular tubercle (tuberculum articulare), and less pronounced retroarticular tubercle (tuberculum retroarticulare), passing into the temporal line. Between the articular and postarticular tubercles a mandibular fossa (fossa mandibularis). It is covered with cartilage and articulates with the condylar process of the lower jaw.

Rice. 1. Temporal bone, right:

a — topography of the temporal bone;

b — external view: 1 — scaly part; 2 - zygomatic process; 3 - articular tubercle; 4 - postarticular tubercle; 5 - mandibular fossa; 6— stony-scaly fissure; 7 — edge of the roof of the tympanic cavity; 8 - petrotympanic fissure; 9 - styloid process; 10 - drum part; 11 - mastoid process; 12— mastoid notch; 13 - external auditory canal; 14—mastoid foramen; 15—supraductal spine; 16 - temporal line; 17 - groove of the middle temporal artery;

c — anterior surface of the pyramid of the temporal bone: 1 — parietal edge; 2 - medullary surface of the scales; 3 - stony-scaly gap; 4 — roof of the tympanic cavity; 5 - arcuate elevation; 6 - groove of the sigmoid sinus; 7 - mastoid foramen; 8 - occipital edge; 9 - groove of the superior petrosal sinus; 10—upper edge of the pyramid; 11 - trigeminal depression; 12—carotid channel; 13 - rocky part; 14 — front surface of the pyramid; 15 — myotubal canal; 16 - wedge-shaped edge; 17 - groove of the lesser petrosal nerve; 18 - groove of the greater petrosal nerve; 19 - cleft canal of the lesser petrosal nerve; 20 - cleft canal of the greater petrosal nerve;

d — view from the inside: 1 — scaly part; 2 - semicircular eminence; 3 - roof of the tympanic cavity; 4 - groove of the sigmoid sinus; 5 - mastoid foramen; 6 - aperture of the vestibular tubule; 7 - styloid process; 8 — aperture of the cochlear tubule; 9 - groove of the inferior petrosal sinus; 10 - internal auditory canal; 11 - groove of the superior sagittal sinus; 12 - zygomatic process;

e - bottom view: 1 - stony-scaly fissure; 2 - petrotympanic fissure; 3 — myotubal canal; 4 - internal aperture of the carotid canal; 5 - top of the pyramid; 6 - lower surface of the pyramid; 7 - groove of the inferior petrosal sinus; 8 - external aperture of the carotid canal; 9 - stony dimple; 10 - condylar tubule; 11 - jugular fossa; 12 - stylomastoid foramen; 13 - groove of the occipital artery; 14 - mastoid notch; 15 - mastoid process; 16 - styloid process; 17 - tympanic-squamosal fissure; 18 - mandibular fossa; 19 - articular tubercle; 20 - zygomatic process

Rice. 2. Cutting the temporal bone through the tympanic cavity:

1 - arcuate elevation; 2 - probe in the elbow of the facial nerve canal; 3 - groove of the greater petrosal nerve; 4 - hemicanal of the tensor tympani muscle; 5 - semi-canal of the auditory tube; 6 - probe in the carotid canal; 7 - probe in the stylomastoid foramen; 8 - mastoid cells; 9 - mastoid cave

Along the outer surface of the squamous part of the temporal bone runs groove of the middle temporal artery (sulcus a. temporalis mediae).

Internal, cerebral surface (fades cerebralis) has cerebral eminences, gyral depressions (finger-shaped); the grooves of the vessels of the meninges run along it.

Human anatomy S.S. Mikhailov, A.V. Chukbar, A.G. Tsybulkin

1. Facial nerve canal (canalis n. facialis) begins at the bottom of the internal auditory canal and extends forward and laterally to the level of the cleft of the greater petrosal nerve canal. A bend is formed here - the elbow of the facial canal (geniculum n. facialis). From the genu the canal runs at a right angle laterally and backward along the axis of the pyramid, then changes horizontal direction to vertical and ends at the posterior wall of the tympanic cavity with the stylomastoid foramen.

2. Sleepy canal (canalis caroticus) begins with an outer aperture on the lower surface of the pyramid, rises vertically and, bending almost at a right angle, opens at the top of the pyramid internal aperture (apertura interna canalis carotid). The internal carotid artery passes through the canal.

3. Musculo-tubal canal (canalis musculotubarius) begins at the top of the pyramid, between its anterior edge and the scales of the temporal bone. It forms part of the auditory tube.

4. Cord tympani canaliculus (canaliculus chordae tympani) starts from the facial nerve canal slightly above the stylomastoid foramen and ends in the petrotympanic fissure. A branch of the facial nerve passes through it - the chorda tympani.

5. Mastoid tubule (canaliculus mastoideum) originates at the bottom of the jugular fossa and ends in the tympanomastoid fissure. A branch of the vagus nerve passes through this canaliculus.

6. Tympanic tubule (canaliculus tympanicus) It arises in the petrosal fossa with an opening through which a branch of the glossopharyngeal nerve, the tympanic nerve, enters. Having passed through the tympanic cavity, its continuation (the lesser petrosal nerve) exits through the cleft of the same name on the anterior surface of the pyramid.

7. Carotid-tympanic tubules (canaliculi caroticotympanici) pass through the wall of the carotid artery canal near its external aperture and open into the tympanic cavity. They serve for the passage of blood vessels and nerves (Table 1).

Table 1. Temporal bone canals

Channels and tubules	What cavities (areas) does it connect?	What's going on in the canal?
Sleepy channel	Outer base of the skull and apex of the pyramid of the temporal bone	Internal carotid artery, internal carotid (autonomic) nerve plexus
Carotid tympanic tubules	Carotid canal (at its beginning) and tympanic cavity	Carotid-tympanic nerves and arteries
Internal auditory canal	Posterior cranial fossa and inner ear	Facial nerve (VII pair of cranial nerves), vestibulocochlear nerve (VIII pair of cranial nerves), artery and vein of the inner ear
Facial nerve canal	The posterior surface of the pyramid of the temporal bone (internal auditory canal) and the stylomastoid foramen (outer base of the skull)	Facial nerve (VII pair of cranial nerves)
Drum string channel	Facial nerve canal, tympanic cavity and petrotympanic fissure (outer base of the skull)	The chorda tympani is a branch of the facial nerve (VII pair of cranial nerves)
Tympanic canaliculus	The inferior surface of the pyramid of the temporal bone (petrosal fossa), the tympanic cavity and the anterior surface of the pyramid (cleft of the lesser petrosal nerve)	Lesser petrosal nerve - branch of the glossopharyngeal nerve (IX pair of cranial nerves)
Musculo-tubal canal	The apex of the pyramid of the temporal bone and the tympanic cavity	Tensor tympani muscle (hemicanal of the tensor tympani muscle), auditory tube (hemicanal of the auditory tube)
Mastoid tubule	Jugular fossa and tympanomastoid fissure	Auricular branch of the vagus nerve (X pair of cranial nerves)
Tubule of the vestibule	Vestibule of the inner ear and posterior cranial fossa (aperture of the vestibular canaliculus)	Aqueduct of the vestibule and vein of the aqueduct of the vestibule
Snail tubule	Vestibule of the inner ear (medial wall of the bony vestibule) and the inferior surface of the pyramid of the temporal bone (aperture of the cochlear canaliculus)	Cochlear aqueduct and cochlear aqueduct vein

Temporal bone canals and their contents

	Channel name	Beginning of the channel	^ End of the channel	Content
	Facial canal(canalis facialis)	Internal auditory canal, meatus acusticus internus	Stylomastoid foramen, foramen stylomastoideum	Facial nerve, n/facialis (VII pair) - ganglion geniculi; - stylomastoid arteries and veins, s., vv. stylomastoideae
	^ Sleepy channel(canalis caroticus)	External carotid foramen, foramen caroticum externum, anterior to the jugular fossa of the outer base of the skull. It goes up, bends at a right angle, goes forward and medially. Opens into the internal carotid foramen.	Internal carotid foramen, foramen caroticum internum	Internal carotid artery, a.carotis interna - venous plexus of the carotid canal, plexus venosus caroticus internus - internal carotid plexus, plexus caroticus internus (from ganglion superius truncus sympathicus)
	^ Muscular- pipechannel(canalis musculotubarius) a) semicanalis m.tensoris tympani b) semicanalis tubae auditivae	Tympanic cavity, cavitas tympani	The tip of the pyramid, apex puramis	Tensor tympani muscle m.tensor tympani auditory tube (tuba auditiva) pars ossea tubae auditivae
	^ Carotid tympanic tubules(canaliculi caroticotympanici)	Sleepy canal, canalis caroticus	Tympanic cavity, cavitas tympanica	Carotid-tympanic arteries, aa.carotico-tympanici (from a. carotis interna); -carotid-tympanic nerves, nn. Caroticotumpanici (from pl. caroticus internus et n. tympanicus)
	^ Mastoid tubule(canaliculus mastoideus)	Jugular fossa, fossa jugularis (foramen mastoideum)	Mastotympanic fissure, fissura tympanomastoidea (apertura canaliculi mastoidei)	Auricular branch of the vagus nerve (X) ramus auricularis n. vagi
	^ Greater petrosal nerve canal(canalis nervi petrosi majoris)	Facial canal in the area, geniculum canalis facialis	Cleft of the greater petrosal nerve, hiatus canalis nervi petrosi majoris	Greater petrosal nerve, n. petrosus major (branch n. facialis)
	^ Drum string channel(canaliculus chordae tympani)	Facial canal in the area of ​​the stylomastoid foramen, foramen stylomastoideum	Petrostympanic fissure, fissura petrotympanica	Drum string, chorda tympani (branch of n. facialis VII pair)
	Tympanic tubule (canaliculus tympanicus)	The lower surface of the pyramid of the temporal bone. Stony dimple, fossula petrosa (apertura inferior canaliculi tympanici)	Cleft of the lesser petrosal nerve, hiatus canalis n. petrosi minoris	Tympanic nerve, n. tympanicus (clade n.glossopharyngeus IX pair)
	Internal auditory canal (meatus acusticus internus)	Posterior cranial fossa and inner ear.	The porus acusticus internus begins on the posterior surface of the pyramid and ends in the inner ear.	Facial nerve (VII), vestibulocochlear (VIII), artery and vein of the inner ear.
	Aqueduct of the vestibule (aqueductus vestibuli)	The vestibule of the inner ear and the posterior cranial fossa (external aperture of the vestibular aqueduct).	From the vestibule to the external aperture of the vestibular aqueduct, aperture aqueductus vestibule externa.	The aqueduct of the vestibule (endolymphatic duct) and the vein of the vestibule aqueduct.
	Plumbing snail (aqueductus cochleae)	The vestibule of the inner ear and the lower surface of the pyramid of the temporal bone (outer aperture of the cochlear canaliculus).	From the vestibule to the external aperture of the cochlear canaliculus, aperture canalis cochleae externa.	Cochlear aqueduct (perilymphatic duct) and cochlear canaliculus vein.

Temporal bone, os temporale, the paired bone has a complex structure, as it performs all 3 functions of the skeleton and not only forms part of the side wall and base of the skull, but also contains the organs of hearing and gravity. It is the product of the fusion of several bones (mixed bone), which independently exist in some animals, and therefore consists of three parts:
1) scaly part, pars squamosa;
2) the drum part, pars tympanica and
3) rocky part, pars petrosa.

During the 1st year of life, they merge into a single bone, closing external auditory canal, meatus acusticus externus, in such a way that the scaly part lies above it, the stony part medially from it, and the tympanic part behind, below and in front. Traces of the fusion of individual parts of the temporal bone remain for life in the form of intermediate sutures and fissures, namely: at the border of pars squamosa and pars petrosa, on the anterior superior surface of the latter - fissura petrosquamos a; in the depths of the mandibular fossa - fissura tympanosquamosa, which is divided by a process of the petrous part into fissura petrosquamosa and fissura petrotympanica(the chorda tympani nerve exits through it).

Scaly part, pars squamosa, participates in the formation of the lateral walls of the skull. It belongs to the integumentary bones, i.e. it ossifies on the basis of connective tissue and has a relatively simple structure in the form of a vertically standing plate with a rounded edge overlapping the corresponding edge of the parietal bone, margo squamosa, in the form of fish scales, which is where its name comes from.

On its brain surface, facies cerebralis, traces of the brain are visible, finger impressions, impressiones digitatae, and ascending upward groove from a. meningea media. The outer surface of the scales is smooth, participates in the formation of the temporal fossa (the anatomy of which is discussed) and is therefore called facies temporalis.

Moves away from her zygomatic process, processus zygomaticus, which goes forward to connect with the zygomatic bone. At its origin, the zygomatic process has two roots: anterior and posterior, between which there is a fossa for articulation with the lower jaw, fossa mandibularis.

On the lower surface of the anterior root is placed articular tubercle, tuberculum articulare, preventing the head of the lower jaw from dislocating forward when the mouth opens significantly.

Drum part, pars tympanica, the temporal bone forms the anterior, lower and part of the posterior edge of the external auditory canal, ossifies endesmally and, like all integumentary bones, has the appearance of a plate, only sharply curved.

External auditory canal, meatus acusticus externus, is a short canal directed inward and somewhat forward and leading into the tympanic cavity. Its upper edge external opening, porus acusticus externus, and part of the posterior edge is formed by the scales of the temporal bone, and along the remaining length by the tympanic part.

In a newborn, the external auditory canal is not yet formed, since the tympanic part is an incomplete ring (annulus tympanicus), covered by the eardrum. Due to such a close position of the eardrum outwards, diseases of the tympanic cavity are more often observed in newborns and young children.

The petrous part, pars petrosa, is so named for the strength of its bone substance, due to the fact that this part of the bone is involved in the base of the skull, and is the bony seat of the organs of hearing and gravity, which have a very thin structure and require strong protection from damage. It develops on the basis of cartilage. The second name of this part is the pyramid, given by its shape as a triangular pyramid, the base of which faces outward, and the apex faces forward and inward towards the sphenoid bone.

The pyramid has three surfaces: front, back and bottom. The anterior surface is part of the bottom of the middle cranial fossa; the posterior surface faces posteriorly and medially and forms part of the anterior wall of the posterior cranial fossa; the lower surface faces down and is visible only on the outer surface of the base of the skull. The external relief of the pyramid is complex and is determined by its structure as a container for the middle (tympanic cavity) and inner ear (bone labyrinth, consisting of the cochlea and semicircular canals), as well as the passage of nerves and blood vessels.

On the front surface of the pyramid, near its apex, a small depression is noticeable, impressio trigemini, from the trigeminal nerve ganglion (n. trigemini,). Outwards pass from him two thin grooves, medial - sulcus n. petrosi majoris, and lateral - sulcus n. petrosi minoris. They lead to two foramina of the same name: the medial one, hiatus candlis n. petrosi majoris, and lateral, hiatus canalis n. petrosi minoris. Outside of these holes, an arched elevation is noticeable, eminentia arcuata, formed due to the protrusion of a rapidly developing labyrinth, in particular the superior semicircular canal.

The surface of the bone between eminentia arcuata and squama temporalis forms the roof of the tympanic cavity, tegmen tympani.

Approximately in the middle of the back surface of the pyramid is internal auditory opening, porus acusticus internus, which leads to internal auditory canal, meatus acusticus internus, where the facial and auditory nerves pass, as well as the artery and veins of the labyrinth.

From the lower surface of the pyramid, facing the base of the skull, a thin pointed styloid process, processus styloideus, serving as a site of muscle attachment "anatomical bouquet"(mm. styloglossus, stylohyoideus, stylopharyngeus), as well as ligaments - ligg. stylohyoideum and stylomandibular. The styloid process represents a part of the temporal bone of branchial origin. Together with lig. stylohyoideum it is a remnant of the hyoid arch.

Between the styloid and mastoid processes is stylomastoid foramen, foramen stylomastoideum, through which n comes out. facialis and a small artery enters. Medial to the styloid process there is a deep jugular fossa, fossa jugularis. Anterior to the fossa jugularis, separated from it by a sharp ridge, is the external opening of the carotid canal, foramen caroticum externum.

The pyramid has three edges: anterior, posterior and upper. The short anterior margin forms an acute angle with the scales. In this corner it is noticeable opening of the myotubal canal, candlis musculo tubarius leading into the tympanic cavity. This channel is divided by a partition into two sections: upper and lower. Upper, smaller, semicanal, semicanalis m. tensoris tympani, contains this muscle, and the lower one, larger, semicandlis tubae auditivae, is the bony part of the auditory tube, which serves to conduct air from the pharynx into the tympanic cavity.

Along the upper edge of the pyramid, separating the anterior and posterior surfaces, there is a clearly visible groove, sulcus sinus petrosi superiors, a trace of the venous sinus of the same name.

Posterior edge of the pyramid anterior to the fossa jugularis connects with the basilar part of the occipital bone and forms together with this bone sulcus sinus petrosi inferioris- trace of the inferior petrosal venous sinus.

The outer surface of the base of the pyramid serves as a place for muscle attachment, which determines its external relief (process, notches, roughness). Downwards it extends into mastoid process, processus mastoideus. The sternocleidomastoid muscle is attached to it, which maintains the head in the balance necessary for an upright position of the body. Therefore, the mastoid process is absent in quadrupeds and even apes and develops only in humans in connection with their upright posture.
On the medial side of the mastoid process there is a deep mastoid notch, incisura mastoidea, - place of attachment of m. digastricus; even more inward - a small furrow, sulcus a. occipitalis, - trace of the artery of the same name.

On the outer surface of the base of the mastoid process, a smooth triangle is distinguished, which is a place for rapid access to the cells of the mastoid process when they are filled with pus.

Inside the mastoid process contains these cells cellulae mastoideae, which are air cavities separated by bone bars that receive air from the tympanic cavity, with which they communicate through antrum mastoideum. On the cerebral surface of the base of the pyramid there is deep groove, sulcus sinus sigmoidei, where the venous sinus of the same name lies.

Canals of the temporal bone. The largest channel is canalis caroticus, through which the internal carotid artery passes. Beginning with its external opening on the lower surface of the pyramid, it rises upward, then bends at a right angle and opens with its internal opening at the apex of the pyramid medial to the canalis musculotubarius.

Facial canal, canalis facialis, begins in the depths porus acusticus internus, from where the canal first runs forward and laterally to the fissures (hiatus) on the anterior surface of the pyramid; at these holes, the canal, remaining horizontal, turns at a right angle laterally and backward, forming a bend - knee, geniculum canalis facialis, and then down and ends through the foramen stylomastoideum, located on the lower surface of the pyramid of the temporal bone, canalis muculotubarius.

Video No. 1: normal anatomy of the temporal bone of the skull

Other video lessons on this topic are:

Video No. 2: normal anatomy of the temporal bone canals

Temporal bone canals. Sleepy canal (canalis caroticus), through which the internal carotid artery and the internal carotid (vegetative) plexus pass into the cranial cavity, begins on the lower surface of the pyramid with the external opening of the carotid canal. Next, the carotid canal rises upward, bends at a right angle, and goes forward and medially. The canal opens into the cranial cavity through the internal carotid foramen.

Musculo-tubal canal (canalis musculotubarius) has a common wall with the carotid canal. It begins at the anterior edge of the pyramid near its border with the squama of the temporal bone, runs posteriorly and laterally, parallel to the anterior edge of the pyramid. The myotubal canal is divided by a septum into two half-canals. Upper semicanal (semicanalis musculi tensoris tympani) is occupied by the muscle of the same name, straining the tympanic membrane, and the lower one - semicanal of the auditory tube (semicanalis tubae auditivae) is the bony part of this tube. Both half-channels open into the tympanic cavity on its anterior wall.

Facial canal (sapalis facialis), in which the facial nerve and blood vessels pass, begins at the bottom of the internal auditory canal. Then, in the thickness of the pyramid of the temporal bone, the facial canal runs horizontally forward, perpendicular to the longitudinal axis of the pyramid. Having reached the level of the cleft of the canal of the greater petrosal nerve, the canal goes laterally and posteriorly at a right angle, forming a bend, or knee of the facial canal (geniculum canalis facialis). Next, the canal follows horizontally backward along the axis of the pyramid to its base, where it turns vertically downward, bending around the tympanic cavity. On the lower surface of the pyramid the canal ends with the stylomastoid foramen.

Cord tympani canaliculus (canaliculus chordae tympani) starts from the canal of the facial nerve slightly above the stylomastoid foramen, goes forward and opens into the tympanic cavity. A branch of the facial nerve passes through this canaliculus - drum string (сhorda tympani), which then exits the tympanic cavity through the petrotympanic fissure.

Tympanic tubule (canaliculus tympanicus) begins with a lower opening in the depths of the stony dimple on the lower surface of the pyramid, then rises upward into the tympanic cavity through its lower wall. Further, the canaliculus continues in the form furrows (sulcus promontorii), on the labyrinthine wall of this cavity on the surface cape (promontorium). The Canadian then pierces the upper wall of the tympanic cavity and ends in the cleft of the lesser petrosal nerve canal on the anterior surface of the pyramid. The tympanic canaliculus contains the tympanic nerve, a branch of the glossopharyngeal nerve.

Mastoid tubule (capaliculus mastoideus) originates in the jugular fossa, crosses the facial canal in its lower part and opens into the tympanomastoid fissure. The auricular branch passes through this canaliculus
vagus nerve.

Carotid-tympanic tubules (canaliculi caroticotympanici) begin on the wall of the carotid canal (near its external opening) and penetrate the tympanic cavity. Both tubules serve to pass the nerves and arteries of the same name into the tympanic cavity.