Temporal canals

1.      Facial canal (canalis nervi facialis)– begins at the bottom of internal acoustic meatus
(meatus acusticus internus) and ends in stylomastoid foramen (foramen stylomastoideum); (serves for
facial nerve)

The bottom of internal acoustic meatus (fundus meatus acustici interni):

Medial
side
                    Lateral side

Facial nerve area
Superior vestibular area

(area nervi facialis)
(area vestibularis superior)




Transversal crest

(crista transversa)

                             Cochlear
area                                                                         Singular foramen

                              (area cochleae)             Inferior vestibular
area                       (foramen singulare)

                          (area vestibularis inferior)


-     The canal has three parts:

-     1. After the canal began at bottom of internal acoustic meatus it goes upright to the
longitudinal axis of pyramis (there goes out the branch called greater petrosal nerve (nervus
petrosus major)).

-     2. Near the greater petrosal nerve hiatus it turns to the lateral side and goes at the medial
wall of middle ear cavity (cavum  tympani). Then the canal is located at the dorsal wall of middle
ear cavity. (paralel with the longitudinal axis)

-     3. The last part of facial canal turns downwards and ends in stylomastoid foramen (foramen
stylomastoideum).





1.       Canaliculus of chorda tympani (canaliculus chordae tympani)  – chorda tympani is branch of
facial nerve and begins in the 3^rd part of facial canal and ends in petrotympanic fissure; (serves
for chorda tympani)

2.       Carotid canal (canalis caroticus) – it starts at inferior surface of pyramis (facies
interiér partis petrosae ossis temporalis) in external aperture of carotid canal (apertura externa
canalis carotici);- it has sigmoid shape (because the blood pressure is too high for nerve tissue,
it could cause demage of brain. So that the function of this canal is to reduce blood pressure
before the blood enters to the brain);-ends at the top of pyramis  in internal aperture of carotid
canal (apertura interna canalis carotici); (serves for internal carotid artery)

3.       Caroticotympanic canaliculi (canaliculi caroticotympanici) – they start within the carotid
canal (canalis caroticus) (first curvature) and end in the middle ear cavity (davům tympani);
(serve for carotycotympanic nerves)

4.       Mastoid canaliculus (canaliculus mastoideus) - starts at the bottom of jugular fossa
(fossa jugularis) and ends in tympanomastoid fissure (fissura tympanomastoidea); (serves for
auricular branch of vagus nerve)

5.       Tympanic canaliculus (canaliculus tympanicus) - starts at the bottom of fossula petrosa
(between the jugular fossa and external aperture of carotid canal), it goes through the middle ear
cavity (davům tympani) and ends in lesser petrosal hiatus; (serves for tympanic nerveàlesser
petrosal nerve)

6.       Musculotubarius canal (canalis musculotubarius) – begins at the top of pyramis more
ventraly than the internal aperture of carotid canal; is devided by the musculotubarial septum
(septum canalis musculotubarii) into two levels: upper (semicanalis musculi tensoris tympani) and
lower (semicanalis tubae auditivae); ends in middle ear cavity (davům tympani);(serves for tensor
tympani muscle and Eustachian tube)

superior


semicanalis musculi tensoris tympani



septum canalis musculotubarii


semicanalis tubae auditivae

                                                              inferior

7. Vestibular canaliculus (canaliculus vestibuli) – this canaliculus is for endolymfa drainage;it
starts in the inner ear and ends at the posterior surface of pyramis in external aperture of
aqueductus vestibuli (apertura externa aqueductus vestibuli)

8. Cochlear canaliculus (canaliculus cochleae) this canaliculus is for perilymfa drainage; it
starts in the inner ear and ends in external aperture of cochlear canaliculus (apertura externa
canaliculi cochleae)