1. Temporal bone. Left bone.
Left lateral view.
Image Name: Fig A - The temporal bone consists of three major parts: squamous, petrous, and tympanic.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

2. Temporal bone. Left bone.
Inferior view.
Image Name: Fig B - The temporal bone consists of three major parts: squamous, petrous, and tympanic.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

3. Temporal bone. Left bone.
Medial view.
Image Name: Fig C - The temporal bone consists of three major parts: squamous, petrous, and tympanic.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

4. Parts of the temporal bone
Left lateral view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

5. Parts of the temporal bone
Inferior view.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

6. Clinical: Structures in the temporal bone
Image Name: Cl. Box A - <p>The mastoid process contains mastoid air cells that communicate with the middle ear; the middle ear in turn communicates with the nasopharynx via the pharyngotympanic (auditory) tube. Bacteria may use this pathway to move from the nasopharynx into the middle ear. In severe cases, bacteria may pass from the mastoid air cells into the cranial cavity, causing meningitis.</p><p> The petrous portion of the temporal bone contains the middle and inner ear as well as the tympanic membrane. The bony semicircular canals are oriented at an approximately 45-degree angle from the coronal, transverse, and sagittal planes.</p><p> Irrigation of the auditory canal with warm (44°C) or cool (30°C) water can induce a thermal current in the endolymph of the semicircular canal, causing the patient to manifest vestibular nystagmus (jerky eye movements, vestibulo-ocular reflex). This caloric testing is important in the diagnosis of unexplained vertigo. The patient must be oriented so that the semicircular canal of interest lies in the vertical plane.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

7. Clinical: Structures in the temporal bone
Image Name: Cl. Box B - <p>The mastoid process contains mastoid air cells that communicate with the middle ear; the middle ear in turn communicates with the nasopharynx via the pharyngotympanic (auditory) tube. Bacteria may use this pathway to move from the nasopharynx into the middle ear. In severe cases, bacteria may pass from the mastoid air cells into the cranial cavity, causing meningitis.</p><p> The petrous portion of the temporal bone contains the middle and inner ear as well as the tympanic membrane. The bony semicircular canals are oriented at an approximately 45-degree angle from the coronal, transverse, and sagittal planes.</p><p> Irrigation of the auditory canal with warm (44°C) or cool (30°C) water can induce a thermal current in the endolymph of the semicircular canal, causing the patient to manifest vestibular nystagmus (jerky eye movements, vestibulo-ocular reflex). This caloric testing is important in the diagnosis of unexplained vertigo. The patient must be oriented so that the semicircular canal of interest lies in the vertical plane.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

8. Clinical: Structures in the temporal bone
Image Name: Cl. Box C - <p>The mastoid process contains mastoid air cells that communicate with the middle ear; the middle ear in turn communicates with the nasopharynx via the pharyngotympanic (auditory) tube. Bacteria may use this pathway to move from the nasopharynx into the middle ear. In severe cases, bacteria may pass from the mastoid air cells into the cranial cavity, causing meningitis.</p><p> The petrous portion of the temporal bone contains the middle and inner ear as well as the tympanic membrane. The bony semicircular canals are oriented at an approximately 45-degree angle from the coronal, transverse, and sagittal planes.</p><p> Irrigation of the auditory canal with warm (44°C) or cool (30°C) water can induce a thermal current in the endolymph of the semicircular canal, causing the patient to manifest vestibular nystagmus (jerky eye movements, vestibulo-ocular reflex). This caloric testing is important in the diagnosis of unexplained vertigo. The patient must be oriented so that the semicircular canal of interest lies in the vertical plane.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

9. Coronal section through right ear, anterior view.
Ear: Overview.
Coronal section through right ear, anterior view.
Image Name: Fig
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

10. External auditory canal.
Coronal section through right ear, anterior view.
Image Name: Fig The tympanic membrane separates the external auditory canal from the tympanic cavity (middle ear). The outer third of the auditory canal is cartilaginous, and the inner two thirds are osseous (tympanic part of temporal bone).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

11. Structure of the auricle.
Right auricle, right lateral view.
Image Name: Fig A - <p>The auricle of the ear encloses a cartilaginous framework that forms a funnel-shaped receptor for acoustic vibrations. The muscles of the auricle are considered muscles of facial expression, although they are vestigial in humans.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

12. Structure of the auricle.
Right auricle, right lateral view.
Image Name: Fig A - <p>The auricle of the ear encloses a cartilaginous framework that forms a funnel-shaped receptor for acoustic vibrations. The muscles of the auricle are considered muscles of facial expression, although they are vestigial in humans.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

13. Structure of the auricle.
Cartilage and muscles of the auricle, right lateral view.
Image Name: Fig B - <p>The auricle of the ear encloses a cartilaginous framework that forms a funnel-shaped receptor for acoustic vibrations. The muscles of the auricle are considered muscles of facial expression, although they are vestigial in humans.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

14. Structure of the auricle.
Cartilage and muscles of the auricle, medial view of posterior surface.
Image Name: Fig C - <p>The auricle of the ear encloses a cartilaginous framework that forms a funnel-shaped receptor for acoustic vibrations. The muscles of the auricle are considered muscles of facial expression, although they are vestigial in humans.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

15. Arteries of the auricle
Right lateral view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

16. Arteries of the auricle
Posterior view of the right auricle.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

17. Innervation of the auricle
Right lateral view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

18. Innervation of the auricle
Posterior view of the right auricle.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

19. Clinical: Curvature of the external auditory canal
Insertion of otoscope.
Image Name: Cl. Box A - <p>The external auditory canal is most curved in its cartilaginous portion. When an otoscope is being inserted, the auricle should be pulled backward and upward so the speculum can be introduced into a straightened canal.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

20. Clinical: Curvature of the external auditory canal
Anterior view.
Image Name: Cl. Box B - <p>The external auditory canal is most curved in its cartilaginous portion. When an otoscope is being inserted, the auricle should be pulled backward and upward so the speculum can be introduced into a straightened canal.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

21. Clinical: Curvature of the external auditory canal
Transverse section.
Image Name: Cl. Box C - <p>The external auditory canal is most curved in its cartilaginous portion. When an otoscope is being inserted, the auricle should be pulled backward and upward so the speculum can be introduced into a straightened canal.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

22. Coronal section through right ear, anterior view.
Ear: Overview.
Coronal section through right ear, anterior view.
Image Name: Fig
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

23. Right petrous bone, superior view.
Middle ear.
Right petrous bone, superior view.
Image Name: Fig The tympanic cavity of the middle ear communicates anteriorly with the pharynx via the pharyngotympanic (auditory) tube and posteriorly with the mastoid air cells.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

24. Tympanic cavity and pharyngotympanic tube.
Medial view of opened tympanic cavity.
Image Name: Fig
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

25. Levels of the tympanic cavity. Anterior view.
Image Name: Fig A - <p>The tympanic cavity is divided into three levels: epi-, meso-, and hypotympanum.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

26. Right tympanic cavity. Anterior view with the anterior wall removed.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

27. Illustrator: Karl Wesker
Tympanic cavity
Anatomical relationships of the tympanic cavity. Oblique sagittal section showing the medial wall.
Image Name: Fig C -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

28. Boundaries of the tympanic cavity
Image Name: Table
Illustrator:
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

29. Auditory ossicles. Left ear.
Auditory ossicles in the middle ear. Anterior view of the left ear.
Image Name: Fig A - The ossicular chain consists of three small bones that establish an articular connection between the tympanic membrane and the oval window.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

30. Auditory ossicles. Left ear.
Bones of the ossicular chain. Medial view of the left ossicular chain.
Image Name: Fig B - The ossicular chain consists of three small bones that establish an articular connection between the tympanic membrane and the oval window.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

31. Malleus ("hammer"). Left ear.
Posterior view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

32. Malleus ("hammer"). Left ear.
Anterior view.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

33. Illustrator: Karl Wesker
Incus ("anvil"). Left ear.
Medial view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

34. Illustrator: Karl Wesker
Incus ("anvil"). Left ear.
Anterolateral view.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

35. Stapes ("stirrup"). Left ear.
Superior view.
Image Name: Fig A -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

36. Stapes ("stirrup"). Left ear.
Medial view.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

37. Lateral view of the right tympanic membrane.
Image Name: Fig A - The tympanic membrane is divided into four quadrants: anterosuperior (I), anteroinferior (II), posteroinferior (III), and posterosuperior (IV).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

38. Tympanic membrane. Right tympanic membrane.
Mucosal lining of the tympanic cavity. Posterolateral view with the tympanic membrane partially removed.
Image Name: Fig B - The tympanic membrane is divided into four quadrants: anterosuperior (I), anteroinferior (II), posteroinferior (III), and posterosuperior (IV).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

39. Ossicular chain in the tympanic cavity.
Lateral view of the right ear.
Image Name: Fig Revealed: Ligaments of the ossicular chain and muscles of the middle ear (stapedius and tensor tympani).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

40. Clinical: Ossicular chain in hearing
Vibration of the tympanic membrane causes a rocking movement in the ossicular chain.
Image Name: Cl. Box A - <p>The mechanical advantage of the lever action of the ossicular chain amplifies the sound waves by a factor of 1.3.</p><p>Sound waves funneled into the external auditory canal set the tympanic membrane into vibration. The ossicular chain transmits the vibrations to the oval window, which communicates them to the fluid column of the inner ear. Sound waves in fluid meet with higher impedance; they must therefore be amplified in the middle ear. The difference in surface area between the tympanic membrane and the oval window increases the sound pressure 17-fold. A total amplification factor of 22 is achieved through the lever action of the ossicular chain. If the ossicular chain fails to transform the sound pressure between the tympanic membrane and the footplate of the stapes, the patient will experience conductive hearing loss of magnitude 20 dB.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

41. Clinical: Ossicular chain in hearing
The stapes in its normal position lies in the plane of the oval window.
Image Name: Cl. Box B - <p>Sound waves funneled into the external auditory canal set the tympanic membrane into vibration. The ossicular chain transmits the vibrations to the oval window, which communicates them to the fluid column of the inner ear. Sound waves in fluid meet with higher impedance; they must therefore be amplified in the middle ear. The difference in surface area between the tympanic membrane and the oval window increases the sound pressure 17-fold. A total amplification factor of 22 is achieved through the lever action of the ossicular chain. If the ossicular chain fails to transform the sound pressure between the tympanic membrane and the footplate of the stapes, the patient will experience conductive hearing loss of magnitude 20 dB.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

42. Clinical: Ossicular chain in hearing
Rocking of the ossicular chain causes the stapes to tilt.
Image Name: Cl. Box C - <p>The movement of the stapes base against the membrane of the oval window (stapedial membrane) induces corresponding waves in the fluid column of the inner ear.</p><p>Sound waves funneled into the external auditory canal set the tympanic membrane into vibration. The ossicular chain transmits the vibrations to the oval window, which communicates them to the fluid column of the inner ear. Sound waves in fluid meet with higher impedance; they must therefore be amplified in the middle ear. The difference in surface area between the tympanic membrane and the oval window increases the sound pressure 17-fold. A total amplification factor of 22 is achieved through the lever action of the ossicular chain. If the ossicular chain fails to transform the sound pressure between the tympanic membrane and the footplate of the stapes, the patient will experience conductive hearing loss of magnitude 20 dB.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

43. Clinical: Ossicular chain in hearing
Propagation of sound waves by the ossicular chain.
Image Name: Cl. Box D - <p>Sound waves funneled into the external auditory canal set the tympanic membrane into vibration. The ossicular chain transmits the vibrations to the oval window, which communicates them to the fluid column of the inner ear. Sound waves in fluid meet with higher impedance; they must therefore be amplified in the middle ear. The difference in surface area between the tympanic membrane and the oval window increases the sound pressure 17-fold. A total amplification factor of 22 is achieved through the lever action of the ossicular chain. If the ossicular chain fails to transform the sound pressure between the tympanic membrane and the footplate of the stapes, the patient will experience conductive hearing loss of magnitude 20 dB.</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

44. Arteries of the middle ear: Ossicular chain and tympanic membrane.
Medial view of the right tympanic membrane.
Image Name: Fig With inflammation, the arteries of the tympanic membrane may become so dilated that their course can be observed (as shown here).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

45. Arteries of the middle ear: Tympanic cavity.
Right petrous bone, anterior view.
Image Name: Fig Removed: Malleus, incus, portions of chorda tympani, and anterior tympanic artery.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

46. Principal arteries of the middle ear
Image Name: Cl. Box
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

47. Principal arteries of the middle ear
Image Name: Table
Illustrator:
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

48. Vestibular apparatus. Right lateral view.
Schematic.
Image Name: Fig A - Ampullary crests and maculae of utricle and saccule shown in red.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

49. Vestibular apparatus. Right lateral view.
Structure of the vestibular apparatus.
Image Name: Fig B -
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

50. Illustrator: Karl Wesker
Auditory apparatus.
Schematic.
Image Name: Fig A - The cochlear labyrinth and its bony shell form the cochlea, which contains the sensory epithelium of the auditory apparatus (organ of Corti).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

51. Compartments of the cochlear canal, cross section.
Auditory apparatus.
Compartments of the cochlear canal, cross section.
Image Name: Fig B - The cochlear labyrinth and its bony shell form the cochlea, which contains the sensory epithelium of the auditory apparatus (organ of Corti).
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

52. Illustrator: Karl Wesker
Auditory apparatus.
Location of the cochlea. Superior view of the petrous part of the temporal bone with the cochlea sectioned transversely.
Image Name: Fig C - <p>The bony canal of the cochlea (spiral canal) makes 2.5 turns around its bony-axis (modiolus).</p><p>The cochlear labyrinth and its bony shell form the cochlea, which contains the sensory epithelium of the auditory apparatus (organ of Corti).</p>
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

53. Innervation of the membranous labyrinth.
Right ear, anterior view.
Image Name: Fig The vestibulocochlear nerve (CN VIII) transmits afferent impulses from the inner ear to the brainstem through the internal acoustic meatus. The vestibulocochlear nerve is divided into the vestibular and cochlear nerves. Note: The sensory organs in the semicircular canals respond to angular acceleration, and the macular organs respond to horizontal and vertical linear acceleration.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,

54. Blood vessels of the inner ear.
Right anterior view.
Image Name: Fig The labyrinth receives its blood supply from the internal auditory artery, a branch of the anteroinferior cerebellar artery.
Illustrator: Karl Wesker
Gilroy et al., THIEME Atlas of Anatomy. All rights reserved. © THIEME 2008,