60 Supra- and Infrahyoid Muscles

Supra- and infrahyoid muscles and pharynx (lateral aspect). Ramus of mandible, pterygoid muscles, and insertion

of temporalis muscle removed. 1 Galea aponeurotica

2 Temporal fascia

3 Tendon of temporalis muscle

4 Zygomatic arch

5 Lateral pterygoid plate

6 Tensor veli palatini muscle (styloid process)

7 Superior constrictor muscle of pharynx

8 Styloglossus muscle

9 Posterior belly of digastric muscle

10 Stylohyoid muscle

11 Longus capitis muscle

12 Sternocleidomastoid muscle (reflected)

13 Inferior constrictor of pharynx

14 Frontal belly of occipitofrontalis muscle

15 Orbital part of orbicularis oculi muscle

16 Buccinator muscle

17 Depressor anguli oris muscle

18 Mylohyoid muscle

19 Anterior belly of digastric muscle

20 Thyrohyoid muscle

21 Sternohyoid muscle

22 Omohyoid muscle

23 Hyoid bone

24 Sternothyroid muscle

Supra- and infrahyoid muscles (schematic drawing). 25 Scalenus muscles

16

18

19

23

22

21

24

10

9

11

20

13

25

Supra- and Infrahyoid Muscles 61

Supra- and infrahyoid muscles and pharynx (lateral aspect). Buccinator muscle removed; oral cavity opened.

1 External acoustic meatus

2 Tensor veli palatini muscle

3 Styloid process

4 Superior constrictor muscle of pharynx

5 Stylopharyngeus muscle (divided)

6 Middle constrictor muscle of pharynx

7 Sternocleidomastoid muscle

8 Greater horn of hyoid bone

9 Longus capitis muscle

10 Inferior constrictor muscle of pharynx

11 Temporal fascia

12 Tendon of temporalis muscle

13 Orbicularis oculi muscle

14 Zygomatic arch

15 Lateral pterygoid plate

16 Parotid duct

17 Gingiva of upper jaw (without teeth),

buccinator muscle (divided)

18 Pterygomandibular raphe

19 Hyoglossus muscle

20 Mylohyoid muscle

21 Anterior belly of digastric muscle (hyoid bone)

22 Sternohyoid and thyrohyoid muscles

23 Omohyoid muscle

62 Section through the Cavities of the Head

1 Temporalis muscle

2 Sphenoidal sinus

3 Nasopharynx

4 Masseter muscle

5 Superior longitudinal, transverse and

vertical muscles of tongue

6 Hyoglossus muscle

7 Geniohyoid muscle

8 Corpus callosum (caudate nucleus)

9 Optic nerve

10 Cavernous sinus

11 Zygomatic arch

12 Cross section of lateral pterygoid

muscle and maxillary artery

13 Section of medial pterygoid muscle

14 Soft palate

15 Mandible and inferior alveolar nerve

16 Septum of the tongue

17 Mylohyoid muscle

18 Submandibular gland

19 Platysma muscle

20 Foramen magnum, vertebral artery and

spinal cord

21 Internal carotid artery

22 Head of mandible

23 Styloid process

24 Inferior alveolar nerve

25 Lingual nerve and chorda tympani

nerve

26 Medial pterygoid muscle

27 Uvula

28 Anterior belly of digastric muscle (cut)

29 Condyle of occipital bone

30 Mastoid process

31 Lateral pterygoid muscle

32 Auditory tube and levator veli palatini muscle

33 Tensor veli palatini muscle

Coronal section through cranial, nasal, and oral cavities at the level of

sphenoidal sinus.

Pterygoid and palatine muscles (posterior aspect).

63

12

13

14

15

16

17

18

19

20

21

22

23

24

1

2

3

4

5

6

7

8

9

10

11

Maxillary Artery

1 Superficial temporal artery

Branches of the first part

2 Deep auricular artery and anterior tympanic artery

3 Middle meningeal artery

4 Inferior alveolar artery

Branches of the second part

5 Deep temporal branches

6 Pterygoid branches

7 Masseteric artery

8 Buccal artery

Branches of the third part

9 Posterior superior alveolar artery

10 Infra-orbital artery

11 Sphenopalatine artery and branches

to the nasal cavity

12 Descending palatine artery

Main branches of maxillary artery (schematic drawing). 13 Artery of the pterygoid canal

Dissection of maxillary artery (lateral aspect). Ramus mandibulae partly removed and canalis

mandibulae opened.

1 Galea aponeurotica

2 Superficial temporal

artery and auriculo -

temporal nerve

3 Occipital artery

and greater occipital

nerve (C2)

4 Temporomandibular

joint (opened)

5 External carotid

artery

6 Mandible and inferior

mandibular artery and

nerve

7 Accessory nerve (Var.)

8 Great auricular nerve

9 Sternocleidomastoi -

deus muscle

10 Punctum nervosum

11 Supraclavicular nerves

12 Supra-orbital nerves

13 Temporalis muscle

14 Transverse facial

artery

15 Masseteric nerve and

deep temporal branch

of maxillary artery

16 Maxillary artery

17 Buccal nerve

18 Lingual nerve

19 Buccinator muscle

20 Facial artery

21 External carotid

artery and sinus

caroticus

22 Hypoglossal nerve

23 Digastric muscle

24 Transverse cervical

nerves

64

III

V

VII

XII

X

I

II

I

II

V1

V2

V3

III

IV

V

VII

IX

XI

XII

X

The twelve cranial nerves emerge

from the brain stem and penetrate

the skull at different places. The

olfactory nerves (n. I) pass the lamina

cribrosa innervating the upper part

of the nasal mucous membrane. The

optic nerve (n. II) is related to the

eye. The external ocular muscles

are innervated by the oculomotor,

trochlear, and abducent nerves (n. III,

n. IV, and n. VI). Facial skin and

masticatory muscles are innervated

by the trigeminal nerve (n. V) while

the facial nerve (n. VII) innervates

mainly the mimic musculature. The

stato-acoustic organ is related to the

vestibulocochlear nerve (n. VIII). The

vagus nerve (n. X) is one of the

longest cranial nerves, running

through the lateral neck region to

reach the thoracic and abdominal

cavities. It belongs to the parasympathetic part of the autonomic nervous

system. The glossopharyngeal (n. IX),

accessory (n. XI), and hypoglossal

(n. XII) nerves innervate the muscles

of the neck, the tongue, and the

pharynx. During human evolution,

they were incorporated secondarily

into the brain cavity.

Schematic drawing of the cranial nerves (indicated by I–XII)

(lateral aspect).

Dissection of the cranial nerves (indicated by I–XII) (lateral aspect). Brain, brain stem,

and cerebellum have been partly removed (from Lütjen-Drecoll, Rohen, Innenansichten des

menschlichen Körpers, 2010).

Cranial nerves

I = Olfactory nerves

II = Optic nerve

III = Oculomotor nerve

IV = Trochlear nerve

V = Trigeminal nerve

VI = Abducent nerve

VII = Facial nerve

VIII = Vestibulocochlear nerve

IX = Glossopharyngeal nerve

X = Vagus nerve

XI = Accessory nerve

XII = Hypoglossal nerve

2.2 Cranial Nerves

Brain and Cranial Nerves

Brain and Cranial Nerves 65

Inferior aspect of the brain with cranial nerves. Midbrain divided.

1 Frontal lobe

2 Temporal lobe

3 Pedunculus cerebri

4 Midbrain (divided)

5 Cerebral aqueduct

6 Splenium of corpus callosum

7 Occipital lobe

8 Olfactory bulb

9 Olfactory tract

10 Optic nerve and optic chiasma

11 Infundibulum

12 Oculomotor nerve (n. III)

13 Mamillary body

14 Substantia nigra

15 Trochlear nerve (n. IV)

66

15

Brain and Cranial Nerves

1 Olfactory sulcus (termination) 13 Cerebellum 25 Facial nerve (n. VII)

2 Orbital gyri 14 Tonsil of cerebellum 26 Vestibulocochlear nerve (n. VIII)

3 Temporal lobe 15 Occipital lobe (posterior pole) 27 Flocculus of cerebellum

4 Straight gyrus 16 Olfactory bulb 28 Glossopharyngeal nerve (n. IX)

5 Olfactory trigone and inferior temporal sulcus 17 Orbital sulci of frontal lobe and vagus nerve (n. X)

6 Medial occipitotemporal gyrus 18 Olfactory tract 29 Hypoglossal nerve (n. XII)

7 Parahippocampal gyrus, mamillary body, and 19 Optic nerve (n. II) and anterior 30 Accessory nerve (n. XI)

interpeduncular fossa perforated substance 31 Vermis of cerebellum

8 Pons and cerebral peduncle 20 Optic chiasma 32 Longitudinal fissure

9 Abducent nerve (n. VI) 21 Optic tract

10 Pyramid 22 Oculomotor nerve (n. III)

11 Inferior olive 23 Trochlear nerve (n. IV)

12 Cervical spinal nerves 24 Trigeminal nerve (n. V)

Cranial nerves. Brain (inferior aspect).

Brain and Cranial Nerves 67

1 Falx cerebri

2 Occipital lobe

3 Straight sinus

4 Tentorium cerebelli

5 Transverse sinus

6 Inferior colliculus of midbrain

7 Rhomboid fossa

8 Medulla oblongata

9 Posterior belly of digastric muscle

10 Internal carotid artery

11 Pharynx (middle constrictor muscle)

12 Hyoid bone (greater horn)

13 Trochlear nerve (n. IV)

14 Facial nerve (n. VII) and

vestibulocochlear nerve (n. VIII)

15 Glossopharyngeal nerve (n. IX)

and vagus nerve (n. X)

16 Accessory nerve (intracranial portion) (n. XI)

17 Hypoglossal nerve (intracranial portion) (n. XII)

18 Accessory nerve (n. XI)

19 Hypoglossal nerve (n. XII)

20 Vagus nerve (n. X) and internal carotid artery

21 External carotid artery

22 Sympathetic trunk and superior cervical ganglion

23 Ansa cervicalis (superior root of

hypoglossal nerve)

24 Glossopharyngeal nerve (n. IX) and

stylopharyngeus muscle

Brain stem and pharynx with cranial nerves (posterior aspect). Cranial cavity opened and cerebellum removed.

68 Brain and Cranial Nerves: Trigeminal Nerve

Dissection of the trigeminal nerve in its entirety. Lateral wall of cranial cavity, lateral wall of orbit, zygomatic arch,

and ramus of the mandible have been removed and the mandibular canal opened.

1 Frontal lobe of cerebrum

2 Supra-orbital nerve

3 Lacrimal nerve

4 Lacrimal gland

5 Eyeball

6 Optic nerve and short ciliary nerves

7 External nasal branch of

anterior ethmoidal nerve

8 Ciliary ganglion

9 Zygomatic nerve

10 Infra-orbital nerve

11 Infra-orbital foramen and terminal branches

of infra-orbital nerve

12 Pterygopalatine ganglion and

pterygopalatine nerves

13 Posterior superior alveolar

nerves

14 Superior dental plexus

15 Buccinator muscle and buccal nerve

16 Inferior dental plexus

17 Mental foramen and mental nerve

18 Anterior belly of digastric muscle

19 Ophthalmic nerve (n. V1)

20 Oculomotor nerve (n. III)

21 Trochlear nerve (n. IV)

22 Trigeminal nerve and pons

23 Maxillary nerve (n. V2)

24 Trigeminal ganglion

25 Mandibular nerve (n. V3)

26 Auriculotemporal nerve

27 External acoustic meatus (divided)

28 Lingual nerve and chorda tympani

29 Mylohyoid nerve

30 Medial pterygoid muscle

31 Inferior alveolar nerve

32 Posterior belly of digastric muscle

33 Stylohyoid muscle

34 Sternocleidomastoid muscle