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Transcript
NECK (pp.1000~1022)
Head – Neck – Trunk
Anterior: lower border of mandible > upper surface of manubrium
Posterior: superior nuchal line > intervertebral disc between CVII and TI
Four compartments separated by cervical fascia:


Visceral compartment – digestive, respiratory, and endocrine
Vertebral compartment – cervical vertebrae, spinal cord, spinal nerves, mm. associated with
vertebra
Vascular compartments – major blood vessels and vagus n.
Borders of triangles:



Anterior triangle – ant. border of SCM m., inf. border of mandible, midline of neck
Posterior triangle – post. border of SCM m., ant. border of trapezius, middle 1/3 of clavicle
Fascia
Superficial fascia – with platysma m. (from superficial thorax fascia to mandible and mm. on face),
innervated by cervical br. of CN VII.
Deep cervical fascia –
1. Investing layer
surrounds neck – Ligamentum nuchae, spinous process of CVII > encloses trapezius m. > roof of post.
triangle > encloses SCM m. > surrounds infrahyoid mm.
attaches to:
Superior – occipital protuberance, sup. nuchal line
Lateral – mastoid process, zygomatic arch
Inferior – spine of scapula, acromion, clavicle, and manubrium of sternum
pierced by:
ext. and ant. jugular vv., lesser occipital, greater auricular, transverse cervical, and
supraclavicular nn., brr. of cervical plexus
2. Prevertebral layer
Surrounds: vertebral column, and muscles:
prevertebral mm., ant. middle, and post. scalene mm. and deep mm. of back
Borders:
Superior Anterior – basilar part of occipital bone, jugular foramen, carotid canal
Lateral – mastoid process
Posterior – superior nuchal line, ext. occipital protuberance
Anterior Anterior surface of transverse processes and bodies of CI to CVII vertebrae
Fascia splits into two layers, and creates a longitudinal fascial space.
Inferior into thorax
Lower lateral as axillary sheath extends from anterior and middle scalene mm. to surround
brachial plexus and subclavian a.
3. Pretracheal layer
surrounds trachea, esophagus, thyroid gland
Superior hyoid bone
G54-1
Anterior trachea, thyroid gland
Inferior upper thoracic cavity
Posterior buccopharyngeal fascia (from base of skull into thoracic cavity)
4. Carotid sheath
surrounds common carotid a., internal carotid a., internal jugular vein, and vagus n.
 Fascial compartments
1. Investing layer – includes other three
2. Prevertebral layer – vertebral column, deep mm. and associated structures
3. Pretracheal layer – visceral compartment (trachea, esophagus, thyroid gland)
4. Carotid sheath – from skull to thorax, with neurovascular structures
 Fascial spaces
As a conduit for spread infection
1. Pretracheal space – b/w investing layer of cervical fascia and pretracheal fascia
2. Retropharyngeal space – b/w buccopharyngeal fascia and prevertebral fascia
3. Space b/w two split layers of prevertebral layer of cervical fascia
Superficial venous drainage
1. External jugular veins
formed by posterior auricular v. and posterior division of retromandibular v.
1. Posterior auricular v. – drains the scalp behind and above ear
2. Retromandibular v. – conjoined by superficial temporal and maxillary vv., splits into:
a. Anterior division – joined by facial v. as common facial v., drain into internal jugular v.
b. Posterior division – joined by posterior auricular v. as external jugular v. > crosses SCM m. to
subclavian v.
3. Other tributes to external jugular v.:
a. Posterior external jugular v. – drains superficial area of back of neck
b. Transverse cervical v. –
c. Suprascapular v. – drains posterior scapular region
2. Anterior jugular veins
variable and inconsistent, from hyoid bone to decent by midline of neck to enter subclavian v.
Two anterior jugular vv. are connected by jugular venous arch.
Anterior triangle of the neck (pp. 1006~968)
1.
2.
3.
4.
Submandibular triangle – inferior border of mandible, anterior and posterior bellies of digastric m
Submental triangle – hyoid bone, anterior bellies of two digastric mm. and midline
Muscular triangle – hyoid bone, superior belly of omohyoid m., anterior border of SCM, midline
Carotid triangle – superior belly of omohyoid m., stylohyoid m., posterior belly of digastric m.,
anterior border of SCM
Muscles
G54-2
Suprahyoid muscles
In submental and submandibular triangles; raise the hyoid bone during swallowing
1. Stylohyoid
Origin:
base of styloid process
Insertion: body of hyoid bone
Function: pull hyoid posterosuperiorly
Innervation: CN VII
2. Digastric
Origin:
Posterior belly – mastoid notch (medial side of mastoid process)
Anterior belly – digastric fossa (lower inside of mandible)
Insertion: tendon between two bellies – body of hyoid bone
Function: raise hyoid bone (when mandible is fixed)
opens mouth (when hyoid is fixed)
Innervation: Posterior belly – CN VII
Anterior belly – CN V3
3. Mylohyoid
Origin:
mylohyoid line on mandible
Insertion: hyoid bone
Function: supports and elevates floor of mouth
Innervation: CN V3
4. Geniohyoid
Origin:
Insertion:
Function:
inferior mental spine of mandible
body of hyoid bone
elevates and pulls hyoid forward (when mandible is fixed)
pulls the mandible downward and inward (when hyoid is fixed)
Innervation: anterior ramus of C1 (carried by CN XII)
Infrahyoid muscles
1. Sternohyoid
Origin:
posterior aspect of sternoclavicular joint and manubrium of sternum
Insertion: body of hyoid
Function: depresses the hyoid
Innervation: ant. rami of C1 to C3 (through ansa cervicalis)
2. Omohyoid
Origin:
Inferior belly – sup. border of scapula
Superior – body of hyoid
Insertion: Intermediate tendon – to clavicle through a fascial sling
Function: depresses and fixes hyoid
Innervation: ant. rami of C1 to C3 (through ansa cervicalis)
3. Thyrohyoid
Origin:
Insertion:
Function:
oblique line on the thyroid cartilage
greater horn and body of hyoid
depresses hyoid; raises larynx (when hyoid is fixed)
G54-3
Innervation: anterior ramus of C1 (carried by CN XII)
4. Sternothyroid
Origin:
post. surface of manubrium of sternum
Insertion: oblique line on the thyroid cartilage
Function: draws larynx downward
Innervation: ant. rami of C1 to C3 (through ansa cervicalis)
Vessels
Carotid system
1. Common carotid arteries
Right common carotid a. – from brachiocephalic trunk
Left common carotid a. – from aorta
Both ascend in carotid sheath, lateral to trachea and esophagus, give no branch until bifurcate.
Each divides into internal and external carotid aa. near the sup. edge of thyroid cartilage, within carotid
triangle.
Carotid sinus (dilation in the beginning of int. carotid a.) contains receptor for blood pressure
(innervated by CN IX).
Carotid body (in the area of bifurcation) contains receptors for blood oxygen (innervated by CN IX
and X).
2. Internal carotid arteries
give no branch > through carotid canal > enters cranial cavity > supplies cerebral hemisphere, eye,
contents of orbit > forehead
3. External carotid arteries



Superior thyroid a. – 1st br. > superior pole of thyroid gland
Ascending pharyngeal a. – 2nd br. > b/w int. carotid a. and pharynx
Lingual a. – branches on the level of hyoid bone > deep to CN XII > b/w middle constrictor and
hyoglossus m.

Facial a. – deep to stylohyoid and post. belly of digastric mm. > b/w submandibular gland and
mandible > over edge of mandible > face

Occipital a. – deep to posterior belly of digastic m. > post. aspect of scalp

Posterior auricular a. – runs posterosuperiorly
Superficial temporal a. – terminal br. > runs upward > divides into ant. and post. brr.
Maxillary a. – through parotid gland > infratemporal fossa > pterygopalatine fossa


Veins
Skull, brain, superficial face, part of neck
Inferior petrosal sinus, sigmoid sinus > through jugular foramen > internal jugular vein >
Collecting tributes from facial, lingual pharyngeal, occipital, superior thyroid, and middle thyroid
vv. > joined by subclavian v. > brachiocephalic v. > superior vena cava (Fig. 8.195, p.995)
Nerves
1. Facial nerve [VII]
through stylomastoid f. > post. belly of digastric m. and stylohyoid m. > platysma m.
G54-4
2. Glossopharyngeal nerve [IX]
through jugular f. > b/w int. carotid a. and int. jugular v. > b/w int. and ext. carotid aa. > gives:
1. motor br. to innervate stylopharyngeus m.
2. sensory br. to carotid sinus
3. sensory br. to pharynx
> base of tongue and palatine tonsil area
3. Vagus nerve [X]
through jugular f. (b/w CN IX and XI) > enters carotid sheath > medial to int. jugular v., int. and
common carotid aa. >
1. motor br. to pharynx
2. sensory br. to carotid body
3. superior laryngeal n. –
ext. br. (to cricothyroid m.)
int. br. (for sensation of mucosa above vocal fold)
4. cardiac br.
4. Accessory nerve [XI]
through jugular f. > b/w int. carotid a. and int. jugular v. > deep to and innervates SCM m. (Fig. 8.170,
p.1015)
5. Hypoglossal nerve [XII]
hypoglossal canal > b/w int. carotid a. and int. jugular v. > lateral to int. and ext. carotid aa. > deep to
ant. belly of digastric m. > medial to hyoglossus m. > innervates tongue (Fig. 8.173, p.1016)
6. Transverse cervical nerve
br. of cervical plexus, from ant. rami of C2 and C3; crosses on SCM m. in the middle part; for
cutaneous innervation of neck (Fig. 8.172, p.1016)
7. Ansa cervicalis (Fig. 8.173, p.1016)
a loop formed from two roots:
Sup. root – C1 ff. carried by CN XII, innervates superior belly of omohyoid m., upper part of
sternohyoid and sternothyroid mm.
Inf. root – C2 and C3 ff. from cervical plexus, innervates inferior belly of omohyoid m., lower part of
sternohyoid and sternothyroid mm.
Thyroid and parathyroid glands
Thyroid gland – a large unpaired gland
Parathyroid gland – 4 of them on posterior surface of thyroid gland
Thyroid gland
Isthmus connecting two lateral lobes crosses on the 2nd and 3rd tracheal rings.
The gland is within pretracheal layer of fascia with pharynx, trachea, and esophagus.
It is the median pharyngeal outgrowth from foramen cecum on the tongue.
Its remains along disappeared thyroglossal duct, including lingual thyroid and pyramidal lobe.
Arterial supply
1. Superior thyroid artery
the 1st br. of ext. carotid a., divides into:
G54-5
Ant. glandular br. – along superior border of gland, anastomoses with br. from the other side
Post. glandular br. – along post. side of gland, anastomoses with br. of inf. thyroid a.
2. Inferior thyroid artery
1st part of subclavian a. > thyrocervical trunk > inf. thyroid a. > inf. pole of thyroid gland
Inf. br. – supplies the lower gland
Ascending br. – supplies parathyroid glands
3. Thyroid ima artery
from brachiocephalic trunk or the arch of aorta; ascends on anterior surface of trachea
Venous and lymphatic drainage (Fig. 8.175 p.1019)
 Sup. thyroid v. (primary) > int. jugular v.
 Middle thyroid vv. (rest) > int. jugular v.
 Inf. thyroid vv. (rest) > brachiocephalic vv.
 Lymph > Paratracheal nodes (along trachea) > Deep cervical nodes (along int. jugular v.)
Recurrent laryngeal nerves
Vagus n. > Recurrent laryngeal n. (left on arch of aorta; right on right subclavian a.) >
ascend in the grooves b/w trachea and esophagus > posterior to thyroid gland > enters larynx
Consider this relationship while surgically removing or manipulating the thyroid gland.
Parathyroid glands
Two pairs (sup. and inf.) in deep surface of lateral lobes of thyroid gland;
Their levels vary from carotid bifurcation to mediastinum.
Inferior parathyroid glands derive from 3rd pharyngeal pouches; superior from the 4th pouches.
Blood supply is from inferior thyroid a.
Location of structures in different regions of the anterior triangle of the neck
Subdivisions of anterior triangle: (Fig. 8.166, p.1011)
1. Submental triangle – ×1, with submental lymph nodes
2. Submandibular triangle – ×2, submandibular gland, submandibular lymph nodes, CN XII,
mylohyoid n., facial a. and v.
3. Carotid triangle – ×2
a. and v.: common, internal, and external carotid aa., int. jugular v.,
Nerves: cervical br. of CN VII, CN X, XI, and XII, transverse cervical n., sup. and inf. roots of ansa
cervicalis
4. Muscular triangle – ×2, sternothyroid, omohyoid, sternohyoid, and thyrohyoid mm., thyroid and
parathyroid glands., pharynx
G54-6
Posterior triangle of the neck (pages 1023-1029)
Connects with upper limb; borders: (Fig. 8.179, p.1023)
 Ant – posterior edge of SCM m.
 Post – anterior edge of trapezius m.
 Base – middle 1/3 of clavicle
 Apex – posterior to mastoid process
 Roof – investing layer of cervical fascia
 Floor – prevertebral layer of cervical fascia, splenius capitis, levator scapulae, scalene mm.
Muscles
Omohyoid m., enclosed in investing fascia
Origin: superior border of scapula
Insert: inferior border of the body of the hyoid bone
Intermediate tendon: fascial sling to clavicle
Superior belly: in anterior triangle
Inferior belly: divides posterior triangle into occipital and subclavian triangles
Function: depresses hyoid bone
Innervation: ansa cervicalis (anterior rami of C1 to C3)
Vessels
1. External jugular vein (Fig. 8.181, p.1025)
Most superficial in posterior triangle, in superficial fascia, crossing on SCM m.,
Tributes: transverse cervical, suprascapular, anterior jugular vv.
2. Subclavian artery and its branches
1st part – from arch of aorta (left) or brachiocephalic a. (right)
2nd part – passes b/w anterior and middle scalene mm., may have a branch (dorsal scapular a.)
3rd part – crosses the base of posterior triangle, to lateral border of 1st rib becoming axillary a.
Dorsal scapular a. – may from 3rd part, descends on med. border of scapula, post. to rhomboid mm.
3. Transverse cervical and suprascapular arteries (Fig. 8.182, p.1026)
brr. of thyrocervical trunk (from 1st part of subcalvian a.),
Transverse cervical a. divides into:
Superficial br. – on deep surface of trapezius m.
Deep br. (dorsal scapular artery) – deep surface of rhomboid mm.
Suprascapular a. – passes over sup. transverse scapular lig., to post. surface of scapula
4. Veins
Subclavian v. – receives external jugular, suprascapular, and transverse cervical vv., passes anterior to
anterior scalene m.
Nerves
1. Accessory nerve
through jugular foramen, passes deep to SCM m. and enters posterior triangle, superficially within
investing layer of cervical fascia, runs deep to and innervates trapezius m.
G55-1
2. Cervical plexus
Formed by anterior rami of (C1) C2 to C4.
 Muscular branches
a. Phrenic n. – from anterior rami of C3, 4, and 5, to diaphragm with sensory and motor innervation
On the anterior surface of anterior scalene m. in prevertebral fascia, enters thorax
b. Muscular brr. to rectus capitis anterior, rectus capitis lateralis, longus colli, and longus capitis mm.
c. Superior and inferior roots of ansa cervicalis – from ant. rami of C1 to C3, innervates infrahyoid
mm.
 Cutaneous branches
Emerges from posterior border of SCM m.
a. Lesser occipital n. – from C2, to the skin of neck and scalp posterior to ear
b. Great auricular n. – from C2 and C3, to the skin of parotid region, ear, and mastoid area
c. Transverse cervical n. – from C2 and C3, to lateral and anterior part of neck
d. Supraclavicular nn. – from C3 to 4, to skin over clavicle till rib 2
3. Brachial plexus
forms from anterior rami of C5 to T1, its roots run b/w anterior and middle scalene mm.
 Upper trunk – from C5 and C6
 Middle trunk – from C7
 Lower trunk – from C8 and T1
In the posterior triangle it gives:
 Dorsal scapular n. – rhomboid mm.
 Long thoracic n. – serratus anterior m.
 Nerve to subclavius
 Suprascapular n. – supraspinatus and infraspinatus mm.
G55-2
Root of the neck (pp.1030-1040)
Borders:
Ant – top of the manubrium of sternum, superior margin clavicle
Post – top of T1 vertebra, superior margin of scapula to coracoid process
Vessels
Subclavian arteries (Fig. 8.187, p.1031)
Right subclavian a. – from brachiocephalic trunk, anterior to pleural cavity in neck, posterior to
anterior scalene m., becomes axillary a. when crosses on lateral border of 1st rib
Left subclavian a. – from arch of aorta
1st part – from origin to medial border of ant. scalene m.
2nd part – posterior to ant. scalene m.
3rd part – from lateral border anterior scalene m. to lateral border of rib 1
1. Vertebral artery
1st br. of subclavian a. entering neck; passes through foramina in transverse processes of CVI to C I
vertebrae; turns medially on the posterior arch of CI; enters posterior cranial fossa through foramen
magnum.
2. Thyrocervical truck
2nd br. from 1st part of subclavian a. > divides into inferior thyroid, transverse cervical, and
suprascapular aa.
2-1. Inferior thyroid artery
From thyrocervical trunk, posterior to carotid sheath, reaches posterior surface of thyroid gland
Ascending cervical a. – anterior to prevertebral mm., for these mm. and spinal cord
2-2. Transverse cervical artery
From thyrocervical trunk > crosses anteriorly to ant. scalene m. > deep surface of trapezius m. >
divides >
 Superficial br. –deep surface of trapezius m.
 Deep br. – deep surface of rhomboid mm., medial to scapula
2-3. Suprascapular a.
From thyrocervical trunk > crosses anteriorly to ant. scalene m., phrenic n., brachial plexus >
superior border of scapula over superior transverse scapular ligament > suprascapular fossa
3. Internal thoracic artery
From subclavian a. > descends posterior to clavicle, large vv. and anterior to pleural cavity > enters
thorax > posterior to ribs and anterior to transverse thoracis m.
4. Costocervical trunk
Arise from the 1st part of left subclavian a., and 2nd part of right subclavian a. > divides into >
4-1. Deep cervical a. – ascends in the back of neck
4-2. Supreme intercostal a. – descends anterior to root of rib 1, into first two intercostal spaces
Veins
Axillary v > lateral border of rib 1 > subclavian v. (anterior to ant. scalene m.) > joined by ext. then int.
jugular vv. > brachiocephalic v.
G56-1
Nerves
1. Phrenic nerves
Ant. rami of C3 to C5 > lateral then anterior to ant. scalene m. > in prevertebral layer of cervical fascia
> between subclavian v. and a. > thorax
2. Vagus nerves [X]
In carotid sheath (b/w common carotid a. and int. jugular v.) > gives cardiac br. (posterior to subcalvian
a.) > vagus n. anterior to subcalvian a.
3. Recurrent laryngeal nerves
From right vagus n. > right recurrent laryngeal n. around subclavian a. > ascends in the groove b/w
trachea and esophagus > larynx
From left vagus n. > left recurrent laryngeal n. around arch of aorta > ascends in the groove b/w
trachea and esophagus > larynx
4. Sympathetic nervous system
Cervical part of the sympathetic trunk
Anterior to longus colli and logus capitis mm. > posterior to carotid sheath > gray rami communicans
to spinal nn. (There is NO white rami communicantes in cervix.)
Ganglia
1. Superior cervical ganglion
Very large at CI and CII, brr. to:
 Plexus on int. and ext. carotid aa.
 C1 to C4 spinal nn. through gray rami communicantes
 Pharynx
 Heart as superior cardiac nn.
2. Middle cervical ganglion
Second ganglion along sympathetic trunk on CVI level, brr. to:
 C5 and C6 spinal nn. through gray rami communicantes
 Heart as middle cardiac nn.
3. Inferior cervical ganglion
Combines with T1 ganglion as cervicothoracic ganglion (stellate ganglion)
anterior to neck of rib 1 and transverse process of CVII; posterior to 1st part of subclavian a.; brr. to:
 C7 and T1 spinal nn. through gray rami communicantes
 Plexus on vertebral a.
 Heart as inf. cardiac nn.
Lymphatics
1. Thoracic duct
Begins at cisterna cyli in abdomen > ascends anterior to vertebral column, posterior to esophagus,
thoracic aorta on the left, azygos v. on the right
On TV level left to esophagus > posterior to left carotid sheath > Joined by:
‧ left jugular trunk – from left head and neck
‧ left subclavian trunk – from left upper limb; terminates at the junction of left int. jugular v. and
left subclavian v.
G56-2
‧ left bronchomediastinal trunk – from left half of thoracic structures
2. On the right:
‧ Right jugular trunk – from head and neck
‧ Right subclavian trunk – from right upper limb
‧ Right bronchomediastinal trunk – from right half of thoracic cavity, right upper intercostal
spaces
Lymphatic of the neck
Superficial nodes – along ext. jugular v.
Deep nodes – along int. jugular v.
Superficial nodes  Superficial nodes ┐
└> Deep nodes  Deep nodes
Superficial lymph nodes
1. Occipital nodes – along occipital a., drains posterior scalp and neck
2. Mastoid nodes (retroauricular / posterior auricular nodes) – along posterior auricular a., drains
posterolateral half of scalp
3. Pre-auricular and parotid nodes – along superficial temporal and transverse facial aa., drains ant.
surface of auricle, anterolateral scalp, upper face, eyelids, and cheeks
4. Submandibular nodes – along facial a, along facial a., drains forehead, gingivae, teeth, and tongue
5. Submental nodes – inferior and posterior to chin, drains center lower lip, chin, floor of mouth, tip of
tongue, lower incisors
Lymphatic flow from superficial lymph nodes:
 Occipital and mastoid nodes > superficial cervical nodes
 Pre-auricular and parotid, submandibular, and submental nodes > deep cervical nodes
Superficial cervical lymph nodes
Along ext. jugular v. on the surface of the SCM m.
Posterior and posterolateral region of scalp > Occipital and mastoid nodes > Superficial cervical nodes
> Deep cervical nodes
Deep cervical lymph nodes
Along int. jugular v., divided into upper and lower groups
1. Jugulodigastric node – most superior, at post. belly of digastric m. on int. jugular v., drains tonsils
and tonsillar region
2. Jugulo-omohyoid node – lower group, at intermediate tendon on int. jugular v., drains tongue
Right – to the right lymphatic duct
Left – to thoracic duct
G56-3
Gray’s Anatomy: by Henry Gray and Peter L. Williams
G56-4
PHARYNX (pp.1040~1052)
Musculofascial half-cylinder, oral and nasal cavities > larynx and esophagus
Borders: Base of skull > top of esophagus (CVI)
Nasal cavities > choanae + pharyngotympanic tubes > nasopharynx
Oral cavity > oropharyngeal isthmus + posterior one-third of tongue > oropharynx
Larynx > laryngeal inlet > laryngopharynx
Retropharyngeal space > vertebral column
Soft palate: Elevate to seal off nasopharynx from oropharynx
Depress to seal off oral cavity from oropharynx
Skeletal framework
Anterior vertical line of attachment for the lateral pharyngeal walls
First part
Posterior edge of medial pterygoid plate – Pterygoid hamulus – Pterygomandibular raphe
Pterygomandibular raphe: from pterygoid hamulus to mandible (posterior to 3rd molar tooth)
Buccinator – superior pharyngeal constrictor
Second part
Styloid process – Stylohyoid ligament – Hyoid bone (lesser horn) – Hyoid bone (greater horn)
Third part
Superior tubercle of thyroid cartilage – Oblique line – Inferior tubercle – Cricoid cartilage
Pharyngeal wall
Muscles
Constrictor muscles
All the constrictors are innervated by CNX.
Superior constrictors
Origin: pharyngeal raphe
Insertion: hamulus, pterygomandibular raphe, and mandible
Palatopharyngeal sphincter: from soft palate, circles inner aspect of pharyngeal wall (blends with superior
constrictor) (Fig. 8.199B, p.1044)
Middle constrictors
Origin: lower stylohyoid ligament, lesser horn of hyoid bone, upper surface, and greater horn
Insertion: pharyngeal raphe
Inferior constrictors
Origin: oblique line of thyroid cartilage, cricoid cartilage
Insertion: pharyngeal raphe
The narrowest part of pharyngeal cavity
Longitudinal muscles
Elevate pharyngeal wall
Stylopharyngeus
G57-1
Origin: medial surface of styloid process
Blend with deep surface of pharyngeal wall
Innervated by CN IX
Salpingopharyngeus
Origin: inferior aspect of pharygotympanic tube
Blend with deep surface of pharyngeal wall
Innervated by CNX
Palatopharyngeus
Also a muscle of soft palate, forms a mucosal fold (palatopharyngeal arch)
Origin: upper surface of palatine aponeurosis
Blend with deep surface of pharyngeal wall
It closes oropharyngeal isthmus.
Palatine tonsil is anterior to the palatopharyngeal arch.
Fascia
Buccopharyngeal fascia: thinner; coating on outer surface of muscle; as a part of pretracheal layer of cervical
fascia
Pharyngobasilar fascia: thicker; lining inner surface
Gaps in the pharyngeal wall and structures passing through them
Provides routes for muscles and neurovascular tissues
‧ Gap above the superior constrictor: with pharyngeal fascia
Levator veli palatini m. passing through the fascia enters soft palate.
Tensor veli palatine m. turning medially around pterygoid hamulus enters soft palate.
‧ Gap between superior and middle constrictors, and posterior border of mylohyoid m.
Largest and most important aperture; passed by stylopharyngeus m., and the muscles, nerves and vessels to
the tongue
‧ Gap between middle and inferior constrictors
Internal laryngeal vessels and nerves passing through thyrohyoid membrane enter larynx.
‧ Gap inferior to inferior constrictor
Recurrent laryngeal nn. and vessels
Nasopharynx
Behind posterior apertures (choanae) of nasal cavity
Pharyngeal isthmus (with underlying palatopharyngeal sphincter) mark the separation between oropharynx
from nasaopharynx.
Pharyngeal tonsil (adenoids): lymphoid tissue at the roof of nasopharynx; occludes nasopharyx while enlarges
Lateral wall: pharyngeal opening of pharyngotympanic tube and the covering mucosal elevation and folds
Torus tubarius: the tubal elevation or bulge caused by the pharyngotympanic tube
Pharyngeal recess: the deep recess posterior to torus tubarius
G57-2
Salpingopharyngeal fold: overlying salpingopharyngeus muscle
Torus levatorius: broad fold continues onto soft palate overlying levator veli palatine muscle
Oropharynx
Posterior to oral cavity, inferior to soft palate, superior to upper margin of epiglottis
Palatoglossal folds (arches) between oropharynx and oral cavity form pharyngeal isthmus.
Ant. wall – upper part of posterior one-third (pharyngeal part) of tongue, with lymphoid tissue (lingual tonsil)
Lat. wall – palatine tonsils between palatoglossal and palatopharyngeal arches
While holding liquid or solid in the mouth, closing oropharyngeal isthmus, by depression of soft palate,
elevation of the back of tongue, moving toward midline of palatoglossal and palatopharyngeal folds
While swallowing, oropharyngeal isthmus is opened; and airway is closed at pharyngeal isthmus and larynx.
Laryngopharynx
Superior margin of epiglottis to top of the esophagus (at CVI)
Ant. – valleculae (a pair of mucosal pouches) between tongue and epiglottis
Lat. – piriform fossae (mucosal recesses) between central larynx and lateral lamina of thyroid cartilage for
directing food into esophagus
Tonsils
Pharyngeal tonsil (adenoids when enlarged) at the roof of nasopharynx
Palatine tonsils at side of oropharynx between palatoglossal and palatopharyngeal arches
Lingual tonsil on the posterior one-third of tongue
Small lymphoid nodules occurs in the pharyngotympanic tube and upper surface of soft palate
Vessels
Arteries
Upper part of pharynx is supplied by:
· Ascending pharyngeal a.
· Ascending palatine and tonsillar brr. of facial a.
· Brr. of maxillary and lingual aa.
Lower part of pharynx:
· Pharyngeal brr. from inferior thyroid a. (br. of thyrocervical trunk)
Palatine tonsil:
· Tonsillar br. of facial a.
Veins
Form a plexus draining to pterygoid plexus (superiorly) and to facial and internal jugular vv. (inferiorly)
Lymphatics
Drain to deep cervical nodes: including retropharyngeal, paratracheal, and infrahyoid nodes
Palatine tonsils – to jugulodigastric nodes
Nerves
Pharyngeal plexus: in the outer fascia; formed by:
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· Pharyngeal br. of vagus n. (from inf. ganglion of vagus n.) with motor and sensory
· Brr. of external laryngeal n. (from superior laryngeal br. of vagus n.)
· Pharyngeal brr. of glossopharyngeal n.
All mm. in pharynx are innervated by vagus n. through pharyngeal plexus, except:
· Stylopharyngeus by a br. of glossopharyngeal n.
Sensory function:
· Nasopharynx – by pharyngeal br. of maxillary n. (V2), originating in pterygopalatine fossa through
palatovaginal canal
· Oropharynx – by glossopharyngeal n. (IX) via pharyngeal plexus
· Laryngopharynx – by vagus n. (X) via pharyngeal plexus
Glossopharyngeal nerve [IX]
Exits through jugular foramen > descends on posterior surface of stylopharyngeus m. >
lateral surface of stylopharyngeus > gap between superior and middle constrictors >
inferior to palatine tonsil > posterior aspect of tongue
Motor to stylopharygeus m.
Sensory to oropharynx – afferent limb of gag reflex
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NASAL CAVITIES (pp. 1069~1087)
Contains olfactory receptors, with skeletal framework, anterior apertures (nares) and posterior apertures
(choanae), a midline nasal septum
Lateral wall
Conchae: three curved shelves of bone, dividing nasal cavity into four air channels
· Inferior nasal meatus – between inferior concha and nasal floor
· Middle nasal meatus – between inferior and middle conchae
· Superior nasal meatus – between middle and superior conchae
· Spheno-ethmoidal recess – between superior chonca and nasal roof
Openings for paranasal sinuses and nasolacrimal duct are on the lateral wall.
Regions
· Nasal vestibule – lined by skin and with hair follicles
· Respiratory region – lined by respiratory epithelium with ciliated and mucous cells
· Olfactory region – apex of cavity, lined by olfactory epithelium with olfactory receptors
Innervation and blood supply
Innervation:
· Olfaction – by olfactory n. (I)
· General sensation – by ophthalmic n. (V1) for anterior region, and maxillary n. (V2) for posterior region
· Glands – by parasympathetic fibers in facial n. (VII) via greater petrosal n. and joined maxillary n.
· Sympathetic fibers – derived from T1 spinal cord; synapse at superior cervical ganglion; postganglionic
fibers along with blood vessels or joining brr. of maxillary n.
Blood supply:
· Terminal brr. of maxillary and facial aa. (from external carotid a.)
· Ethmoidal brr. of ophthalmic a. (from internal carotid a.)
Skeletal framework
Unpaired ethmoid, sphenoid, frontal, and vomer bones
Paired nasal , maxillary, palatine, and lacrimal bones, and inferior conchae
Ethmoid bone
Contains: two ethmoidal labyrinths united by a cribriform plate, and a perpendicular plate
Each ethmoidal labyrinth is with ethmoidal cells between a lateral sheet of bone (orbital plate) and medial
sheet of bone (upper lateral wall)
Medial sheet – superior and middle conchae and a prominent bulge (ethmoidal bulla)
Ethmoidal infundibulum – connects bulla to frontal sinus
Uncinate process – on inferior surface of ethmoidal labyrinth
Maxillary hiatus – between medial wall of maxilla and inferior concha
Ethmoidal notch of frontal bone – filled by cribriform plate
Perforations of cribriform plate are for fibers of olfactory nn.
Crista galli – on superior surface of cribriform plate, anchors falx cerebri of dura mater
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Perpendicular plate – forms upper part of medial nasal septum; articulates with:
Posterior – sphenoidal crest of sphenoid bone
Anterior – nasal spine of frontal bone
Inferior – septal cartilage and vomer
External nose
Bony part – nasal bones, and parts of maxillary and frontal bones
Cartilage part – lateral processes of septal cartilage, major alar and minor alar cartilages
Paranasal sinuses
Outgrowths of nasal cavities into bones
· Lined by respiratory mucosa (ciliated and mucus secreting)
· Open into nasal cavities
· Innervated by brr. of trigeminal n. (V)
Frontal sinuses
Most superior of sinuses; drains into lateral wall of middle meatus via frontonasal duct, and continues as
ethmoidal infundibulum to semilunar hiatus
Innervated by br. of supra-obital n. (from ophthalmic n.); blood supplied by br. of anterior ethmoidal aa.
Ethmoidal cells
Variable number of air chambers;
· Anterior ethmoidal cells – open into ethmoidal infundibulum or frontonasal duct
· Middle ethmoidal cells – into ethmoidal bulla
· Posterior ethmoidal cells – lateral wall of superior meatus
Innervated by:
· Anterior and posterior ethmoidal brr. (of nasociliary n. from ophthalmic n. V1)
· Maxillary n. (via orbital brr. from pterygopalatine ganglion)
Blood is suppied by the brr. of anterior and posterior ethmoidal aa.
Maxillary sinuses
Largest paranasal sinus; a pyramidal shape with its base on the medial wall and apex toward lateral
Opening is near the top of base in the center of semilunar hiatus.
· Superolateral surface – roof to orbit
· Anterolateral surface – roots of upper molar and premolar teeth
· Posterior wall – infratemporal fossa
Sphenoidal sinuses
TWO in the body of sphenoid bone
Opens on the posterior wall of spheno-ethmoidal recess
· Superior – pituitary gland and optic chiasm
· Lateral – cavernous sinus
· Below and front – nasal cavity
Pituitary gland in the hypophyseal fossa can be reached through nasal cavity, its posterior wall, sphenoidal sinus
and its top wall.
Innervation: posterior ethmoidal br. of ophthalmic n. (V1)
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maxillary n. (V2) via brr. of pterygopalatine ganglion
Blood supply: brr. of pharyngeal aa. of maxillary aa.
Walls, floor, and roof
Medial wall
Nasal septum separates two nasal cavities; consists of:
Septal nasal cartilage, perpendicular plate of ethmoid bone, vomer, nasal spine of frontal bone, and the nasal
crest of maxillary and palatine bones, rostrum of sphenoid bone and incisor crest of maxilla
Floor
Consists of the soft tissue of the ext. nose, upper surface of hard palate (palatine process of maxilla and
horizontal plate of palatine bone)
Superior aperture of the incisive canal on the floor
Roof
Consists of:
Anteriorly: central region cribriform plate ethmoid bone, nasal spine of frontal bone and nasal bones, lateral
processes of septal cartilage and major alar cartilage
Posteriorly: anterior surface of sphenoid bone, ala of vomer and adjacent sphenoidal process of palatine bone,
and vaginal process of medial plate of pterygoid process
Openings of roof: cribriform plate, foramen for anterior ethmoidal n. and vessels, opening of sphnoidal sinus
Lateral wall
Bony structures: ethmoidal labyrinth and uncinate process; perpendicular plate of palatine bone
Cartilages: lateral process of septal cartilage, major and minor cartilages
Ethmoidal bulla, semilunar hiatus, and uncinate process
Ethmoidal infundibulum on the front end of semilunar hiatus curves up and as frontonasal duct to frontal
sinus
·
·
·
·
·
Nasolacrimal duct – lateral wall of inferior meatus
Frontal sinus – through frontonasal duct, then ethmoidal infundibulum, to lateral wall of middle meatus
Middle ethmoidal cells – above ethmoidal bulla
Posterior ethmoidal cells – lateal wall of superior meatus
Maxillary sinus – semilunar hiatus
Nares
Anterior openings of nasal cavities
Held open by alar cartilages and septal cartilage
Can be widened by nasalis m., depressor septi nasi, and levator labii superioris alaeque nasi
Choanae
Openings between nasal cavities and nasopharynx; with bony margins:
Inferior – posterior border of horizontal plate of palatine bone
Lateal – posterior margin of medial plate of pterygoid process
Medial – posterior border of vomer
Roof – ala of vomer, vaginal process of medial plate of pterygoid process (anteriorly)
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body of sphenoid bone (posteriorly)
Gateways
Cribriform plate
· Perforations for the fibers of olfactory nn. (I),
· anterior ethmoidal n. (from orbit to cranial cavity, then nasal cavities),
· foramen cecum for connection between nasal vv. to superior sagittal sinus
Sphenopalatine foramen
On the posterolateral wall of superior meatus
Formed by the sphenopalatine notch in palatine bone and body of sphenoid bone
Communicates nasal cavity and pterygopalatine fossa, passed by:
· Sphenopalatine br. of maxillary a.
· Nasopalatine br. of maxillary n. (V2)
· Superior nasal brr. of maxillary n. (V2)
Incisive canal
In the floor of each nasal cavity
There are TWO incisive canals. Both opens to a incisive fossa in the roof of oral cavity. It transmits:
· Nasopalatine nerve from nasal cavity into oral cavity
· Terminal end of the greater palatine a. form oral cavity into nasal cavity
Small foramina in the lateral wall
· Internal nasal brr. of infra-orbital n. of maxillary n. (V2) and alar brr. of nasal a. (from facial a.) around
margin of naris from face
· Inferior nasal brr. of greater palatine br. of maxillary n. (V2) from palatine canal on lateral wall
Vessels
Rich vascular supply to increase the humidity and temperature of respired air.
Arteries
· External carotid a. and brr. > Sphenopalatine, greater palatine, superior labial, and lateral nasal aa.
· Internal carotid a. and brr. > Anterior and posterior ethmoidal aa.
1. Sphenopalatine artery
The largest one, the terminal br. of maxillary a., divides into:
· Posterior lateral nasal brr. – large part of lateral wall; anastomose with ant. and post. ethmoidal aa., and
lateral nasal brr. of facial a.
· Posterior septal brr. – over roof and then nasal septum, anastomose with terminal end of greater palatine a.,
and superior labial a.
2. Greater palatine artery
Passing through incisive canal form roof of oral cavity into nasal cavity
3. Superior labial and lateral nasal arteries
· Superior labial artery – from facial a., alar br. to lateral aspect of naris, septal br. into nasal cavity
· Lateral nasal artery – from facial a., for supplying external nose. Alar br. for lateral margin of naris and
nasal vestibule
4. Anterior and posterior ethmoidal arteries
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From ophthalmic a. > medial wall of orbit > between ethmoidal labyrinth and frontal bone > supply paranasal
sinus > enter cranial cavity
· Posterior ethmoidal artery – through cribriform plate > upper parts of medial and lateral walls
· Anterior ethmoidal artery – through slit-like foramen lateral to crista galli > medial and lateral walls >
deep surface of nasal bones > passing between nasal bone and lateral nasal cartilage > skin of external nose
The major sites for nose-bleed (epistaxis) – anterior region of medial wall, with extensive anastomoses between
greater palatine, sphenopalatine, superior labial, and anterior ethmoidal aa.
Veins
Brr. originating from maxillary a. drain into pterygoid plexus of veins in infratemporal fossa
Vv. from anterior region of nasal cavity join facial v.
Nasal v. in some individuals passes through forament cecum, and connects to superior sagittal sinus. It is
regarded as an emissary v., by which infection may enter cranial cavity.
Ant. and post. ethmoidal vv. are tributes of superior ophthalmic v. draining to carvernous sinus.
Innervation
· Olfactory n. (I) for olfaction
· Brr. of ophthalmic (V1) and maxillary (V2) for general sensation
· Secretomotor innervation of mucous glands – by parasympathetic fibers. from facial n. (VII) through
pterygopalatine ganglion, joining maxillary n. (V2)
Olfactory nerve [I]
Receptors in olfactory epithelium > through perforations of cribriform plate > synapse with neurons in olfactory
bulb of brain
Branches from the ophthalmic nerve [V1]
Anterior and posterior ethmoidal nerves
Originate from nasociliary n. of ophthalmic n.; the nerves travel with vessels
· Anterior ethmoidal n. – supplies mucosa of ethmoidal air cells; nasal cavity, cranial cavity, and passes to
external nose, terminates as external nasal n.
· Posterior ethmoidal n. – mucosa of ethmoidal air cells, sphenoidal sinus
Branches from the maxillary nerve [V2]
Pass through sphenopalatine foramen
·
·
·
·
Posterior superior lateral nasal nerves – lateral wall of nasal cavity
Posterior superior medial nasal nerves – from roof to septum
Nasopalatine nerve – medial wall of nasal cavity, through incisive canal, to roof of oral cavity
Posterior inferior nasal nerves – from greater palatine n. in palatine canal, through small foramina on the
lateral wall of nasal cavity
· Small nasal nerve – from anterior superior alveolar br. of infra-orbital n., to supply lateal wall near anterior
end of inferior concha.
Parasympathetic innervation
Secretomotor innervation for mucous glands in nasal cavities and paranasal sinuses are carried by:
Greater petrosal n. (pregangionic fibers) > synapse at pterygopalatine ganglion in pterygopalatine fossa >
Brr. of maxillary n. (postganglionic fibers) > Glands
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Sympathetic innervation
Regulating blood flow in nasal mucosa
Spinal cord level T1 > Spinal nerve > white ramus > Sympathetic trunk (preganglionic fibers) > synapse at
superior cervical ganglion > Postganglionic fibers on internal carotid a. > Deep petrosal n. > enters
pterygopalatine fossa > hike on brr. of maxillary n. > nasal cavity
Lymphatics
Anterior region of nasal cavity – passing around nares > face > submandibular nodes
Posterior region of nasal cavity and paranasal sinuses – (retropharygeal nodes >) upper deep cervical nodes
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ORAL CAVITY (pages 1087-1119)
· Roof: hard and soft palates
· Floor: muscular diaphragm and tongue
· Lateral wall: cheeks merge anteriorly with lips surrounding oral fissure (the anterior opening of oral cavity)
· Posterior aperture: oropharyngeal isthmus (can be closed by soft palate and tongue)
Separated by upper and lower dental arches (teeth and alveolar bones) into:
 Oral vestibule:
 Oral cavity proper
Joint for elevating and depressing the mandible: temporomandibular joint
Functions of oral cavity:
 Inlet for digestive system, processing food
 Manipulate the sounds
 Used for breathing and accessing by physician
Multiple nerves innervate the oral cavity
Predominantly by trigeminal nerve (CN V)
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
Brr. of maxillary nerve (CN V2): sensory for upper part of oral cavity
Brr. of mandibular nerve (CN V3): sensory for lower part of oral cavity
Brr. of facial nerve (CN VII): taste (special afferent) for oral part and tongue, distributed by brr. of CN V
Brr. of facial nerve (CN VII): parasympathetic fibers to glands within oral cavity, distributed by brr. of CN V
T1 spinal nerve sympathetic fibers: synapse at superior cervical ganglion, along brr. of CN V or blood
vessels
All muscles of tongue: by hypoglossal nerve (CN XII); except palatoglossus (by CN X)
All muscles of soft palate by vagus nerve (CN X), except tensor veli palatine (by CN V3)
Mylohyoid muscle by CN V3
Skeletal framework
Paired – maxillae, palatine and temporal bones
Unpaired – mandible, sphenoid, and hyoid bone
Cartilaginous part of pharyngotympanic tubes
Maxillae
Involved with the formation of the oral cavity
Alveolar process
Palatine processes: join at midline suture, forms anterior 2/3 of hard palate
Incisive fossa: with a incisive canal extends to each of two nasal cavities
Incisive canal: passed by greater palatine vessels and nasopalatine nerve
Palatine bones
L-shaped, horizontal plate and pyramid process form the roof of the oral cavity
Posterior nasal spine: at the posterior margin of hard palate
Greater palatine foramen: on horizontal plate as the inferior opening of palatine canal
Palatine canal: transmitting greater palatine nerve and vessels from pterygopalatine fossa
Lesser palatine foramen: inferior opening of lesser palatine canal, transmitting lesser palatine nerve and
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vessels to soft palate
Pyramidal process: between medial and lateral plates of pterygoid process of sphenoid bone
Sphenoid bone
Spine of sphenoid bone: posteromedial to foramen spinosum; its medial aspect is attached by tensor veli
palatini
Pterygoid hamulus: as a pulley of tensor veli palatine (Fig. 8.265A, p.1107), and attached by
pterygomandibular raphe (joined by superior constrictor of pharynx and buccinator muscle of cheek, and
attaches inferiorly to mandible) (Fig. 8.247, p.1092)
Scaphoid fossa: medial to foramen ovale and lateral to the root of medial plate of pterygoid process;
attached by tensor veli palatini
Temporal bone
Styloid process:
· attached by stylohyoid ligament (connects to lesser horn of hyoid bone)
· attached by styloglossus muscle on anterolateral aspect
Petrous part of the temporal bone: by muscle associated to soft palate
Stylomastoid foramen: posterior to the root of styloid process
Inferior aspect of temporal bone (triangular roughened area): anteromedial to opening of carotid canal;
attached by levator veli palatini muscle
Cartilaginous part of the pharyngotympanic tube
Between (anterior margin of the petrous part of the) temporal bone and (posterior margin of the greater wing
of the) sphenoid bone
Membranous lamina: inferolateral wall of the tube; attached by tensor veli palatini muscle
Medial end of the tube opens into the nasopharynx
Mandible
Lower jaw; with left and right bodies fusing at midline (mandibular symphysis) and two rami
Alveolar arch: anchors the lower teeth
Mental foramen: on external surface
Superior and inferior mental spines (genial spines): on the posterior surface of mandibular symphysis
Mylohyoid line: on the internal surface of body, separates sublingual fossa and submanidbular fossa
Retromolar triangle: attached by pterygomandibular raphe (which extends superiorly to pterygoid
hamulus) (Fig. 8.245A, p.1091)
Mandibular foramen: on the medial surface of ramus; transmitted by inferior alveolar nerve and vessels
Hyoid bone
With body, greater horn, and lesser horn (attached by stylohyoid ligament); the key bone in the neck
Walls: the cheeks
Skin, fascia, skeletal (buccinator) muscle, oral mucosa
Buccinator
A facial expression muscle; connected with superior constrictor with pterygomandibular raphe
Originates from pterygomandibular raphe, alveolar part of mandible, and alveolar process of maxilla
Blends with orbicularis oris muscle and inserts to modiolus
Innervated by buccal branch of the facial nerve; general sensation is by buccal branch of mandibular n.
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Floor
1. Muscular diaphragm composed by paired mylohyoid mm.
2. Geniohyoid mm. above diaphragm
3. Tongue
With salivary glands (sublingual glands and oral part of submandibular glands) and ducts
Mylohyoid muscles
Originates from mylohyoid line to midline raphe, and attaches to hyoid bone
Functions: 1. supports floor of oral cavity
2. elevates and pulls forward hyoid bone
3. depress the mandible and open mouth
Innervated by the nerve to mylohyoid, from inferior alveolar nerve of mandibular nerve (CN V3)
Geniohyoid muscles
From inferior mental spines of mandible to hyoid bone
Functions: 1. pulls hyoid bone and larynx forward during swallowing
2. depresses mandible to open mouth
Innervated by a branch of cervical nerve C1 hiking on hypoglossal nerve (CN XII)
Gateway into the floor of the oral cavity
· Triangular aperture:
· Formed by the posterior free border of mylohyoid muscle, superior constrictors, and inferior constrictors
· Infratemporal fossa and upper neck connect to oral cavity
· Structures passing through: tongue, hyoglossus, styloglossus, lingual a. and v., lingual, hypoglossal, and
glossopharyngeal nerves, lymphatics, oral part of submandibular gland
Tongue
Apex of tongue, root of tongue (attach to mandible and hyoid bone)
Anterior 2/3 (horizontal plane) and posterior 1/3 (vertical plane) are separated by terminal sulcus of tongue
Foramen cecum of tongue: at the apex of V-shaped sulcus
Thyroglossal duct extends from foramen cecum to thyroid gland in some people
Papillae
· Filiform papillae: cone-shaped projections
· Fungiform papillae: rounder, along the margins
· Vallate papillae: 8 to 12 blunt-end cylindrical papillae, anterior to terminal sulcus of tongue
· Foliate papillae: linear folds of mucosa on the side of tongue
Inferior surface of tongue
Single frenulum of tongue: connect midline sagittal septum to the floor of oral cavity
Ligual veins
Fimbriated fold
Pharyngeal surface
With small lymph nodules of lymphoid tissue (lingual tonsils), but no papillae
Muscles
Intrinsic and extrinsic muscles in pairs are innervated by hypoglossal nerve (CN XII), EXCEPT
palatoglossus muscle by vagus nerve (CN X)
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Intrinsic muscles
· Superior longitudinal muscle
· Inferior longitudinal muscle
· Transverse muscle
· Vertical muscle
Functions:
1. lengthening and shortening
2. curling and uncurling apex and edges
3. flattening and rounding surface
Extrinsic muscles
Functions:
1. protrude tongue
2. retract tongue
3. depress tongue
4. elevate tongue
Genioglossus
Origin:
superior mental spine of mandible
Insertion: hyoid bone and blends with intrinsic mm.
Functions: 1. depress the central part of tongue
2. protrude the anterior part of tongue (stick the tongue out)
Clinical:
The abnormal CN XII (on the left) causes the tongue sticking toward left.
Hyoglossus
Origin:
greater horn of hyoid
Insertion: tongue
Innervation: Hypoglossal n. (XII)
An important landmark
Lingual a. goes medial to hyoglossus m., and lateral to genioglossus m.
Hypoglossal n. and lingual n. enter tongue lateral to hyoglossus m.
Styloglossus
Origin:
anterior surface of styloid process
Insertion: pass between superior, middle constrictors, and mylohyoid m.
To the lateral surface of tongue, blend with hyoglossus m.
Function: retract the tongue
Innervation: hypoglossal n.
Palatoglossus
Origin:
undersurface of palatine aponeurosis
Insertion: lateral side of tongue
Functions: elevate the back of tongue; move palatoglossal arch toward the midline; depress soft palate
Facilitate closing of the oropharyngeal isthmus
Innervation: Vagus n. (X)
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Vessels
Arteries
Lingual artery
External carotid a. > Lingual a. > Passes through aperture (superior and middle constrictors, mylohyoid m.) >
Runs between hyoglossus and genioglossus mm. > Apex of tongue
Supplies: tongue, sublingual gland, and oral mucosa of floor of oral cavity
Veins
Deep lingual veins
On the undersurface of tongue; travels with hypoglossal n. to lateral surface of tongue; joins int. jugular v.
Dorsal lingual vein
With lingual a. runs between hyoglossus and genioglossus mm.; drains to int. jugular v.
Innervation
Glossopharyngeal nerve [IX]
Taste sensation and general sensation from pharyngeal part of tongue
Passes through jugular foramen > Posterior surface of stylopharyngeus m. >
Passes through the aperture (superior and middle constrictors, mylohyoid m.) >
Below inferior pole of palatine tonsil > Pharyngeal part of tongue and vallate papillae
Lingual nerve
General sensation from anterior two-third (oral part) of tongue; and mucosa on the floor of oral cavity and
gingiva with lower teeth
Trigeminal n. (V) > Mandibular n. (V3) > Foramen ovale > Infratemporal fossa >
Passes through the aperture (superior and middle constrictors, mylohyoid m.) >
Medial surface of mandible at last molar tooth deep to gingival (PALPATABLE) (Fig.258, p.1101) >
Under submandibular duct > On lateral surface of hyoglossus m. >
Carries: parasympathetic fibers and taste fibers from oral part of tongue (from facial n. VII)
Facial nerve [VII]
Special sensation (SA, special afferent): from tongue and oral cavity > Lingual n. > Chorda tympani n. >
Facial N. (VII)
Hypoglossal nerve [XII]
All muscles of tongue are innervated by hypoglossal n., EXCEPT palatoglossus m. by vagus n. (X)
Passes through hypoglossal canal > At angle of mandible turn forward >
Crosses laterally to occipital, external, and internal carotid aa. >
Lateral to the hyoglossus m >
Carries: anterior ramus of C1 fiber > Gives superior root of ansa cervicalis > Gives:
· Branch to thyrohyoid m.
· Branch to geniohyoid m.
Lymphatics
Drain to deep cervical chain of nodes along internal jugular v.
· Pharyngeal part of tongue > Pharyngeal wall > Jugulodigastric node of deep cervical chain
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· Oral part of tongue > Mylohyoid m. > Submental and submandibular nodes > Deep cervical node
Submental node – between digastric mm.
Submandibular node – floor of oral cavity along inferior margin of mandible
· Tip of tongue > Mylohyoid m. > Submental nodes > Jugulodigastric node of deep cervical chain
Salivary glands
Most are small glands in submucosa or mucosa lining the tongue, palate, cheeks, and lips
Three pairs of large glands:
Parotid glands
Margins of triangular-shaped trench:
Sternocleidomastoid m., ramus of mandible, and external acoustic meatus to zygomatic arch
Parotid duct crossed masseter m., penetrates buccinator m., open into oral cavity adjacent to 2nd molar tooth
It encloses external carotid a., retromandibular v., and origin of facial n. (VII)
Submandibular glands
Hook-shaped, larger part below mylohyoid m.; smaller part loops around post. margin of mylohyoid m.
Submandibular duct opens at sublingual caruncle (papilla). beside frenulum of tongue.
Sublingual glands
Smallest, almond shaped, lateral to submandibular duct, on medial surface of mandible,
Numerous minor sublingual ducts open to crest of sublingual fold on the floor of oral cavity
Vessels
· Parotid gland – supplied by brr. of external carotid a.; drained to ext. jugular v.; lymph drains to parotid
node, then to superficial and deep cervical nodes
· Submandibular and sublingual glands – by brr. of facial and lingual aa.; drained to facial and lingual vv.;
lymph drains to submandibular node, then to jugulo-omohyoid node
Innervation
Parasympathetic
All salivary glands in oral cavity are innervated by facial n. (VII), whose brr. joining maxillary (V2) and
mandibular (V3) nn.
Parotid gland is by glossopharyngeal n. (IX), whose br. joining mandibular n. (V3)
Greater petrosal nerve
For salivary glands above oral fissure, mucus gland in nose, and lacrimal gland
Preganglionic parasympathetic fibers in facial n. > Greater petrosal n. > Synapse at pterygopalatine ganglion >
Postganglionic fibers > Maxillary n. (V2) > Palatine nn. > Roof of oral cavity
Chorda tympani
For salivary glands below oral fissure, including the small glands on the floor of oral cavity
Preganglionic parasympathetic fibers in facial n. > Chorda tympani n. > Joining lingual n. >
Synapse at submandibular ganglion >
Postganglionic fibers > Submandibular and sublingual glands
G59-6
Roof--palate
Anterior hard palate and posterior soft palate
Hard palate
Respiratory mucosa – covers upper surface as the floor of nasal cavities
Oral mucosa – covers lower surface as the roof of oral cavity
Bone – palatine processes of maxillae; horizontal plate of palatine bones
Adjacent with upper alveolar arch and soft palate
Transverse palatine folds (palatine rugae) and longitudinal ridge (palatine raphe), which ends as incisive
papilla anteriorly
Soft palate
A valve that:
· Depress – to close oropharyngeal isthmus
· Elevate – to separate nasopharynx from oropharynx
Uvula – at the center of posterior free margin of soft palate
Muscles of the soft palate
Four muscles that move the soft palate:
Tensor veli palatini m. and levator veli palatini m. (descend into palate)
Palatoglossus m. and palatopharyngeus m. (ascend into palate)
Musculus uvulae – associated with uvula
All muscles of palate are innervated by vagus n. (X), EXCEPT tensor veli palatini m. by mandibular n. (V3)
1. Tensor veli palatini and the palatine aponeurosis
Muscular part (vertical) descends on the lateral surface of medial pterygoid plate; at the pterygoid hamulus
merges as a tendon, and turns medially to form fibrous part (horizontal) as palatine aponeurosis
Functions:
tenses soft palate; opens pharygotympanic tube (during yawning or swallowing)
2. Levator veli palatini
descends from the under surface of the petrous portion of
temporal bone; (Fig. 8.265, p. 1107)
attaches to upper surface of palatine aponeurosis
Function: elevates the soft palate and close pharyngeal
isthmus between masopharyngx and oropharynx
Innervation: by vagus n. through pharyngeal br. to
pharyngeal plexus
Test: Ask patient say “Ah”; the palate should elevate at
midline; the palate deviates away from abnormal side
Posterior View
3. Palatopharyngeus
Palatopharyngeal arches: on the pharyngeal wall; posterior and medial to palatoglossal arches
G59-7
Functions:
Innervation:
1. depress palate; move arches toward medline; close oropharyngeal isthmus
2. elevate pharynx during swallowing
vagus n. though pharyngeal br. to pharyngeal plexus
4. Palatoglossus
From inferior surface of palatine aponeurosis to lateral surface of tongue
Underline the palatoglossal arches; define lateral margin of oropharyngeal isthmus
Palatine tonsil is between palatoglossal and palatopharyngeal arches
Function:
depress palate; move palatoglossal arches toward midline, elevate back of tongue;
close oropharyngeal isthmus
Innervatoin: vagus n. though pharyngeal br. to pharyngeal plexus
5. Musculus uvulae
From posterior nasal spine, dorsal to palatine aponeurosis; to connective tissue of uvula
Function:
retracts uvula; helps closing pharyngeal isthmus
Innervation: vagus n. though pharyngeal br. to pharyngeal plexus
Vessels
Arteries
1. Ascending palatine artery and palatine branch
1-1. Ascending palatine artery: ext. carotid a. > facial a. > ascending palatine a. > soft palate
1-2. Palatine branch of ascending pharyngeal a.: ext. carotid a. > ascending pharyngeal a. > palatine a. > soft
palate
2. Greater palatine artery
2-1. Greater palatine artery: ext. carotid a. > maxillary a. > greater palatine a.
2-2. Lesser palatine branch: ext. carotid a. > maxillary a. > lesser palatine a.
Veins
Drain to: pterygoid plexus of veins in infratemproal fossa > Pharyngeal plexus > Facial v.
Lymphatics
Deep cervical nodes
Innervation
Greater and lesser palatine nn. and nasopalatine n.
General sensation: maxillary n. (V2)
Parasympathetic nerve fibers: from brr. of facial n
Sympathetic nerve fibers: from T1 spinal cord to blood vessels mainly
1. Greater and lesser palatine nerves
Pterygopalatine fossa > Pterygoid canal > Palate at:
Greater palatine foramen > hard palate and gingival (as far as premolar teeth)
G59-8
Lesser palatine foramen > soft palate
2. Nasopalatine nerves
Pterygopalatine fossa > Sphenopalatine foramen > Roof of nasal cavity > Medial wall > Incisive canal >
Gingiva and mucosa of incisors and canine
Oral fissure and lips
Lips: transitional lining of mucosa internally, to skin externally; with thin skin (vermilion)
Philtrum – vertical shallow groove by fusion of medial nasal processes
Median labial frenulum – connects lip to gum
Orbicularis oris m. – sphincter of orifice
Contours of oral fissure – buccinator, levator labii superioris, zygomaticus major and minor, levator anguli oris,
depressor labii inferioris , depressor anguli oris and platysma
Oropharyngeal isthmus
Lateral – palatoglossal arches
Superior – soft palate
Inferior – sulcus terminalis of tongue
Causes of closure: 1. elevation of back of tongue
2. depression of palate
3. medial movement of palatoglossal arches
4. medial movement of palatopharyngeal arches
Teeth and gingivae
Alveolar arches – mandible (below) and maxillary (above)
Gingivae (gums): muscosa covering teeth and adjacent alveolar bone
Teeth:
Lateral > Molar > Premolar > Canine > Incisor > Midline
Teeth (number)
M – P – C – I ︱ I – C – P – M Superior alveola
M – P – C – I ︱ I – C – P – M Inferior alveola
Adult teeth (32) 3 – 2 – 1 – 2 ︱ 2 – 1 – 2 – 3
3–2–1–2 ︱ 2–1–2–3
Baby teeth (20)
2–0–1–2 ︱ 2–1–0–2
(Deciduous teeth) 2 – 0 – 1 – 2 ︱ 2 – 1 – 0 – 2
Vessels
Arteries (from maxillary a. directly or indirectly)
1. Inferior alveolar artery
Maxillary a. > Inferior alveolar a. > Mandibular canal > Incisor and mental brr. > Mental foramen
2. Anterior and posterior superior alveolar arteries
Maxillary a. > Posterior superior alveolar a. > Small foramina on posterolateral surface of maxilla >
Canals in bone > Molar and premolar teeth
Maxillary a. > Pterygopalatine fossa > Infraorbital a. > Inferior orbital fissure > Orbit > Infraorbital groove >
Infraorbital canal > Anterior superior alveolar a. > Incisor and canine teeth
3. Gingival supply
G59-9
Side facing oral vestibule or cheek
Side facing tongue or palate
· Inferior alveolar a. > buccal gingiva of lower teeth
· Lingual a. of tongue > lingual gingiva of lower teeth
· Ant. and post. superior alveolar aa. > buccal gingival of upper teeth
· Nasopalatine a. > palatine gingival of incisor and canine teeth
· Greater palatine a. > palatine gingival of molar and premolar teeth
Veins
Upper and lower teeth > Superior and inferior alveolar vv. > Pterygoid plexus >
1. Maxillary v. > Retromandibular v. > Jugular system
2. Emissary v. > Cavernous sinus (Infection originating from teeth > cranial cavity)
Anterior teeth > Tributes of facial v. > Facial v.
Teeth > Mental foramen > Facial v.
Gingivae > Facial v. > Pterygoid plexus of vv.
Lymphatics
Teeth and gingivae > Submandibular, submental nodes > Deep cervical nodes
Innervation
By brr. of trigeminal nerve (V)
1. Inferior alveolar nerve
Mandibular n. (V3) > Inf. alveolar n. > All lower teeth > divides:
1-1. Incisive br. > First premolar, canine, incisor teeth; buccal gingiva
1-2. Mental n. > mental foramen > Chin and lower lip
2. Anterior, middle, and posterior superior alveolar nerves
Maxillary n. (V2) > Anterior, middle, and posterior sup. alveolar nn. > Upper teeth
2-1. Maxillary n. > Post. sup. alveolar n. in pterygopalatine fossa > Pterygomaxillary fissure > Superior
alveolar plexus > Maxillary sinus and molar teeth
2-2. Maxillary n. > Infraorbital n. > Middle sup. alveolar n. > Superior alveolar plexus > Premolar teeth
2-3. Maxillary n. > Infraorbital n. > Anterior sup. alveolar n. > Superior alveolar plexus > Canine and
incisor teeth
3. Innervation of gingivae
By trigeminal n. (V)
· Brr. of maxillary n. (V2) > Anterior, middle, and posterior sup. alveolar nn. > Buccal gingivae of upper teeth
· Brr. of maxillary n. (V2) > Nasopalatine n. > Palatine gingivae of upper incisor and canine teeth
· Brr. of maxillary n. (V2) > Greater palatine n. > Palatine gingivae of upper premolar and molar teeth
· Brr. of mandibular n. (V3) > Mental br. > Buccal gingivae of lower incisor, canine, and premolar teeth
· Brr. of mandibular n. (V3) > Buccal n. > Buccal gingivae of lower molar teeth
· Brr. of mandibular n. (V3) > Lingual n. > Lingual gingivae of all lower teeth
G59-10
LARYNX (pp. 1052~1069)
above – pharynx and oropharyngeal isthmus
below – trachea
Functions – valve to lower respiratory tract and instrument producing sound
Composition:
 Unpaired cartilages – cricoid, thyroid, and epiglottis
 Paired cartilages – arytenoids, corniculate, and cuneiform
 Fibroelastic membrane and intrinsic muscles
Swallowing: move larynx upward and forward, closes laryngeal inlet and opens esophagus
Motor and sensory – by CN X (vagus n.)
Laryngeal cartilages
1. Cricoid cartilage
Posterior – lamina of cricoid cartilage; anterior – arch of cricoid cartilage
Facets –
Superolateral surface – for arytenoid cartilages
Lateral surface – for inferior horn of thyroid cartilage
2. Thyroid cartilage
Largest one, fusion by right and left laminae, with palpable laryngeal prominence (Adam’s apple)
Angle between two laminae – 90o (for men); 120o (for women)
Superior thyroid notch – palpable
Inferior thyroid notch – less distinct
Superior horn – connects to greater horn of hyoid bone through a ligament
Inferior horn – connects with cricoid cartilage
Oblique line – for attachments of extrinsic mm. of larynx (sternothyroid, thyrohyoid, and inferior
constrictor)
Superior and inferior tubercles –
3. Epiglottis
Leaf-shaped cartilage, connects with thyroid cartilage via thyro-epiglottic ligament
Epiglottic tubercle – on inferior part of posterior surface
4. Arytenoid cartilages
Base of arytenoid cartilage; apex of arytenoid cartilage
Base – articulates with lamina of cricoid cartilage
Apex – articulates with corniculate cartilage
Medial surface – faces each other
Anterolateral surface – depression for vocalis muscle and vestibular ligament
Vocal process – anterior angle of base of arytenoid cartilage, for vocal ligament
Muscular process – lateral angle, for posterior and lateral crico-arytenoid mm.
5. Corniculate
On the apex of arytenoid cartilage
G60-1
6. Cuneiform
Club-shaped in fibroelastic membrane (between arytenoid and epiglottis cartilages)
Extrinsic ligaments
1. Thyrohyoid membrane
A tough fibroelastic ligament, between superior margin of thyroid cartilage and hyoid bone
Apertures on lateral surfaces for superior laryngeal aa., nn., and lymphatics
Lateral thyrohyoid ligaments – thickening in the posterior borders
Median thyrohyoid ligament – thickening in midline
Triticeal cartilage – in lateral thyrohyoid ligament
2. Hyo-epiglottic ligament
From midline of epiglottis to body of hyoid
3. Cricotracheal ligament
From lower border of cricoid cartilage to upper border of 1st tracheal cartilage
Intrinsic ligaments
Fibro-elastic membrane of larynx
In two parts: lower – cricothyroid ligament; upper – quadrangular membrane
1. Cricothyroid ligament (cricovocal membrane, cricothyroid membrane)
From arch of cricoid cartilage to a upper free margin (from thyroid cartilage to vocal process of
arytenoids cartilage)
Vocal ligament – thickening of the free margin covered in the vocal fold
Median cricothyroid ligament – on midline between inferior notch of thyroid and arch of cricoid
Perforation at median cricothyroid ligament establishes emergency airway. However, occasionally
pyramidal lobe of thyroid gland is there.
2. Quadrangular membrane
between lateral margin of epiglottis and anterolateral surface of arytenoid, and corniculate cartilages
Vestibular ligament – free lower margin in vestibular fold
A gap is between vestibular ligament and vocal ligament.
Laryngeal joints
1. Cricothyroid joints
Between inferior horn of thyroid cartilage and cricoid cartilage,
Allow thyroid cartilage moving forward and tilting downward, and thus tightening vocal ligaments
2. Crico-arytenoid joints
Between the base of arytenoid and cricoid cartilages
Movement: rotation of arytenoid, and sliding of arytenoid cartilages toward or away from each other
Abduction and adduction of vocal ligaments.
Cavity of the larynx
Lined with mucosa, supported by fibro-elastic membrane of larynx and laryngeal cartilages
Superior aperture (laryngeal inlet) – posterior to tongue, can be closed by epiglottis
G60-2
Ant. border – mucosa covering epiglottis
 Lat. border – mucosal folds (aryepiglottic folds), and underlying cuneiform and corniculate cartilges
 Post. border – muscosal fold as a interarytenoid notch
Inferior opening – lumen of trachea

Division into three major regions
1. Vestibule
Vestibular folds – vestibular ligaments and soft tissues
2. Laryngeal ventricles – middle part of laryngeal cavity
Vocal folds – vocal ligaments and soft tissues
3. Infraglottic space
Laryngeal ventricles and saccules
b/w vestibular folds and vocal folds
Laryngeal saccule – extension of ventricle, with mucous glands in wall
Rima vestibuli and rima glottidis
Rima vestibuli – triangular-shaped opening b/w vestibular folds
Rima glottidis – narrower triangular-space b/w vocal folds, with interarytenoid fold as the base
Both rima vestibuli and rima glottidis can be opened and closed.
Intrinsic muscles
Acting to cricothyroid and crico-arytenoid joints
Adjusting the distance b/w epiglottis and arytenoid cartilage
Pull vocal ligaments
Forcing soft tissues with quadrangular membranes and vestibular ligaments toward midline
1. Cricothyroid muscles

Oblique part
Origin: arch of cricoid cartilage
Insertion: inferior horn of thyroid cartilage

Straight part
Origin: arch of cricoid cartilage
Insertion: posteroinferior margin of thyroid lamina
Function: pull thyroid cartilage forward and rotate it down, lengthen vocal folds
Innervation: by superior laryngeal n. of CN X (other intrinsic mm. are by recurrent laryngeal n.)
2. Posterior crico-arytenoid muscles
Origin: posterior surface of cricoid lamina
Insertion: muscular processes of arytenoid cartilages
Function: abduct and externally rotate arytenoid cartilages; open rima glottides, primary abductors of
vocal folds
Innervation: recurrent laryngeal brr. of CN X
3. Lateral crico-arytenoid muscles
Origin: upper surface of arch of cricoid cartilage
Insertion: muscular processes of arytenoid cartilages
Function: adduct and internally rotate arytenoid cartilages
G60-3
Innervation: recurrent laryngeal brr. of CN X
4. Transverse arytenoids muscle
A single muscle connects two arytenoid cartilages
Function: adduct arytenoid cartilages
Innervation: recurrent laryngeal brr. of CN X
5. Oblique arytenoids muscles
Two oblique arytenoid mm.
Origin: from muscular process of a arytenoid cartilage
Insertion: the apex of the other arytenoid cartilage; some fibers continue to aryepiglottic folds as
aryepiglottic part
Function: narrow the laryngeal inlet, constricting the distance b/w arytenoids cartilages and epiglottis
Innervation: recurrent laryngeal brr. of CN X
6. Vocalis
Lateral to and parallel with vocal ligaments
Origin: Lateral surface of vocal processes, and anterolateral depression of arytenoid cartilages
Insertion: thyroid cartilage
Function: adjust the tension of vocal folds
Innervation: recurrent laryngeal brr. of CN X
7. Thyro-arytenoid muscles
Broad flat mm. lateral to fibro-elastic quadrangular membrane of larynx, laryngeal ventricle, and
saccule
Insertion: thyro-epiglottic part into aryepiglottic fold, to the margin of epiglottis
Function: sphincter of vestibule; pull arytenoid cartilage forward; pull epiglottis toward arytenoid
cartilage
Innervation: recurrent laryngeal brr. of CN X
Functions of the larynx
Sphincter of lower respiratory tract; producing sound; change the dimensions of rima glottis, rima
vestibule, vestibule, and laryngeal inlet
1. Respiration
Quiet respiration: laryngeal inlet, vestibule, rima vestibule, and rima glottidis
Force inspiration: posterior crico-arytenoid mm. laterally rotate the arytenoid cartilages, increase the
diameter of laryngeal airways
2. Phonation
Arytenoid cartilages and vocal folds are adducted; air is forced to pass through closed rima glottidis to
produce sound
3. Effort closure
Air is retained in thoracic cavity to stabilize the trunk, or to increase the intra-abdominal pressure.
Rima glottidis, rima vestibuli and lower vestibule are completely closed.
4. Swallowing
Rima glottidis, rima vestibuli and vestibule are closed. Epiglottis closes or narrows laryngeal inlet.
Up and forward movement of the larynx opens esophagus.
G60-4
Prevents the solid and liquid from entry into airway; facilitates the movement through piriform fossae
into esophagus.
Vessels
Arteries
1. External carotid a.  superior thyroid a.  superior laryngeal a.  passes through thyrohyoid
membrane with superior laryngeal n.  larynx
2. Subclavian a.  Thyrocervical trunk  inferior thyroid a.  ascends in the groove b/w esophagus
and trachea  deep to margin of inferior constrictor m.  passes b/w thyroid and cricoid cartilages
Veins
1. Superior laryngeal v.  superior thyroid v.  internal jugular v.
2. Inferior laryngeal v.  inferior thyroid v.  left brachiocephalic v.
Lymphatics
1. Above vocal folds – follows superior laryngeal a.  deep cervical nodes associated with bifurcation
of common carotid a.
2. Below vocal folds – deep nodes associated with inferior thyroid a., or nodes associated with front of
cricothyroid ligament
Nerves
Sensory and motor innervation – by CN X brr.
1. Superior laryngeal nerves
Inferior vagal ganglion  descends medial to int. carotid a.  divides at level of greater horn of hyoid:
1. External laryngeal n. – along lateral wall of pharynx, to supply and penetrate the inferior
constrictor of pharynx and to supply cricothyroid m.
2. Internal laryngeal n. – penetrates thyrohyoid membrane for the sensory of laryngeal cavity down
to vocal folds
2. Recurrent laryngeal nerves
Sensory to laryngeal cavity below level of vocal folds
Motor to all intrinsic mm. of larynx except for cricothyroid
Left recurrent laryngeal n. originates at arch of aorta in thorax; right at right subclavian a. in the root
of neck.
Both ascend in the grooves b/w esophagus and trachea  deep to the margin of inferior constrictor of
pharynx  enter larynx
G60-5
EAR (pp. 953~971)
organ of hearing and balance
· External ear – part attached to lateral aspect of head; canal leading inward
· Middle ear – cavity in the lateral part of petrous part of temporal bone; a membrane separating from
ext. ear; a narrow tube connecting to pharynx
· Internal ear – cavities within the petrous part of temporal bone b/w middle ear and int. acoustic
meatus; with receptors to motion and position
Sound to external ear  mechanical signals in middle ear  electrical signals in internal ear  brain
External ear
1. Auricle
with cartilage covered by skin, to capture the sound,
helix with lobule; concha of auricle; external acoustic meatus; tragus; antitragus; antihelix
Muscles
· Intrinsic mm. – between cartilaginous parts of auricle
· Extrinsic mm. – anterior, superior, and posterior auricular mm., from skull or scalp to auricle
Motor innervation – CN VII
Innervation
Sensory innervation:
· Outer more superficial surfaces – by great auricular and lesser occipital nn. (from cervical plexus)
and auriculotemporal n. (of CN V3)
· Deeper parts of auricle – by brr. from CN VII and X
Vessels
External carotid a.  1. posterior auricular a., 2. superficial temporal a., 3. occipital a.
vv. run along with aa.
Lymph – anteriorly to parotid nodes, posteriorly to mastoid nodes, possibly upper deep cervical nodes
2. External acoustic meatus
from the deepest part of concha to the tympanic membrane, an inch (2.5 cm)
wall with cartilage (lateral 1/3) and bone (medial 2/3), and covered by skin with hairs and modified
sweat glands secreting cerumen
To examine pulling auricle superiorly, posteriorly, and laterally
Innervation
Sensory inputs – auriculotemporal n. (CN V3); auricular br. of CN X,; minorly from CN VII
3. Tympanic membrane
tilting inferiorly and anteriorly;
through a fibrocartilaginous ring attaching to tympanic part of temporal bone
Its internal surface attached by lower end of the handle of malleus.
Umbo (center) of tympanic membrane; cone (reflection) of light;
G61-1
Lateral process of malleus; anterior and posterior malleolar folds;
pars flaccida – thin part above the folds
pars tensa – rest part
Innervation
Sensory of skin (outer surface) – primarily by CN V; additionally by CN VII and X
Sensory of mucous membrane (inner surface) – by CN IX
Middle ear
Air-filled, mucous membrane-lined, in temporal bone, b/w tympanic membrane (lateral) and lateral
wall of inner ear (medial); two parts – 1. tympanic cavity, 2. epitympanic recess
Communicates with: 1. mastoid area (posterior), 2. nasopharynx (through pharyngotympanic tube,
anterior)
Boundaries
Tegmental wall
Tegmen tympani – roof, separates middle ear from middle cranial fossa
Jugular wall
Floor, separates middle ear from jugular fossa
Small aperture on medial border for tympanic branch from glossopharyngeal n. (IX)
Membranous wall
Lateral wall – tympanic membrane
Mastoid wall
Lower part of posterior wall – separates tympanic cavity (middle ear) from mastoid air cells
Aditus to the mastoid antrum locates on posterior wall of epitympanic recess.
Pyramidal eminence – passed by tendon of stapedius m.
Opening for chorda tympani n. (br. of facial n.)
Anterior wall
Lower part separates tympanic cavity from internal carotid a.
Superiorly, opening of pharyngotympanic tube, and opening for canal of tensor tympani muscle
Labyrinthine wall
Separates middle and internal ear; with promontory produced by basal coil of cochlea
· Tympanic plexus – nerve plexus covering the promontory; consists of:
A. Tympanic br. of glossopharyngeal n., with:
1. Parasympathetic nerve fibers – to form lesser petrosal n. > across ant. surface of petrous
part of temporal bone > middle cranial fossa > foramen ovale > otic ganglion
2. Sensory nerve fibers (for the sensation of mucous membrane of middle ear, mastoid area,
and pharyngotympanic tube)
·
·
·
·
B. Brr. from internal carotid plexus, with sympathetic nerve fibers
Oval window – attached by base of stapes (footplate)
Round window – attached by secondary tympanic membrane
Prominence of facial canal – passed by facial n. (VII)
Prominence of lateral semicircular canal –
G61-2
Mastoid area
Epitympanic recess > Aditus > Mastoid antrum (mastoid air cells)
Separates from middle cranial fossa by tegmen tympani
Infection of mastoid area spreads from middle ear.
Pharyngotympanic tube
Connects middle ear with nasopharynx (opening at posterior to inferior meatus of nasal cavity)
· Bony part – lateral one-third
· Cartilaginous part – medial two-thirds
Vessels
External carotid a. > Ascending pharyngeal a.
External carotid a. > Maxillary a. > Middle meningeal a. & Artery of pterygoid canal
Drains to pterygoid plexus of veins
Innervation
Glossopharyngeal n. (IX) > Tympanic br. > Tympanic plexus > Mucous membrane lining
pharyngotympanic tube, tympanic cavity, internal surface of tympanic membrane, mastoid antrum, and
mastoid cells
Auditory ossicles
Tympanic membrane > Malleus > Incus > Stapes > Oval window
1. Malleus
Head – articulates to incus
Neck –
Anterior process – attaches to anterior wall
Lateral process – attaches to anterior and posterior malleolar folds of tympanic membrane
Handle – attaches to tympanic membrane
2. Incus
Body – articulates with malleus
Short limb – to upper posterior wall of middle ear
Long limb – with the end articulating with stapes
3. Stapes
Head – articulates with incus
Two limbs – attach to oval base
Base – fits into oval window on medial wall of middle ear
Muscles associated with the ossicles
1. Tensor tympani
Originates in a bony tube above the pharyngotympanic tube;
Inserts to handle of malleus;
Innervated by mandibular n. (V3);
Function: tenses the tympanic membrane, reduces the vibration
G61-3
2. Stapedius
Originates inside the pyramidal eminence
Inserts to the neck of stapes
Innervated by br. of facial n. (VII)
Function: responds to loud noises, prevents excessive oscillation of stapes
Vessels
1. Maxillary a. > Tympanic br.
2. Occipital a. or posterior auricular a. > Mastoid br.
3. Smaller brr. from:
· middle meningeal a.,
· ascending pharyngeal a.,
· a. of pterygoid canal, and
· tympanic br. (from internal carotid a.)
Venous blood to pterygoid plexus of veins, and superior petrosal sinus
Innervation
Mucous membrane lining middle ear (including mastoid area and pharyngotympanic tube) is by:
Tympanic plexus – locates on the mucous membrane covering promontory; and is formed by:
· Glossopharyngeal n. (IX) > Jugular foramen (exits skull) > Tympanic br. > Re-enters skull >
Middle ear
· Internal carotid plexus > Caroticotympanic nn. > Middle ear
Tympanic plexus (containing preganglionic parasympathetic ff.) > Lesser petrosal n. >
through a hiatus on the anterior surface of petrous part of temporal bone (exits middle ear) >
Floor of middle cranial fossa > Foramen ovale (exits skull) > Otic ganglion
Internal ear
A series of bony cavities (bony labyrinth) and membranous ducts and sacs (membranous labyrinth)
Organ of hearing: cochlear duct; by cochlear n. of vestibulocochlear n. (VIII)
Organ of balance: semicircular ducts, utricle, and saccule; by vestibular n. of vestibulocochlear n.
(VIII)
Bony labyrinth
Central part: vestibule
Posterosuperior: semicircular canals
Anterior: cochlea
Semicircular canals
Anterior, posterior, and lateral semicircular canals; each is at right angle to the other two, and with an
ampulla
Cochlea
Twists into 21/2 ~23/4 turns around modiolus, which is entered by cochlear n.
The lamina of modiolus (spiral lamina) circles around modiolus.
Base of cochlea (posteromedial) and apex (anterolateral)
Cochlear duct separates scala vestibule and scala tympani, which connect at apex through helicotrema.
Scala vestibule – continuous with vestibule
G61-4
Scala tympani – continuous with secondary tympanic membrane covering round window
Cochlear canaliculus – connects scala tympani (filled with endolymph) with subarachnoid space
Membranous labyrinth
A continuous system of ducts (semicircular and cochlear ducts) and sacs (utricle and saccule)
Cochlear duct (ant.) > Saccule > Utricle (middle in vestibule) > Semicircular ducts (post.)
Organs of balance
3 semicircular ducts, utricle and saccule
Utricle, saccule, and endolymphatic duct
Semicircular ducts (three), each with dilated ampulla, connect to utricle
Utriculosaccular duct connects utricle with saccule.
Endolymphatic duct, branching from utriculosaccular duct, expands into endolymphatic sac, an
extradural pouch on the posterior surface of petrous part of temporal bone (in posterior cranial fossa).
Sensory receptors
Macula of utricle, macula of saccule, and cristae of ampullae in semicircular ducts
Organs of hearing
Cochlear duct
Spiral duct with triangular-shaped cross section; filled with endolymph;
with spiral ligament as outer wall, vestibular membrane as roof, and basilar membrane as floor
Vessels
Bony labyrinth –
‧ Maxillary a. > Anterior tympanic br.
‧ Posterior auricular a. > Stylomastoid br.
‧ Middle meningeal a. > Petrosal br.
Membranous labyrinth –
‧ Basilar a. > (Anterior inferior cerebellar a.) > Labyrinthine a. > Internal acoustic meatus > divides
into:
1. Cochlear br. > through modiolus > cochlear duct
2. Vestibular brr. > Vestibular apparatus
Venous drainage: Vestibular and cochlear vv. > join into Labyrinthine v. >
Inferior petrosal sinus or Sigmoid sinus
Innervation
Lateral surface of brainstem between pons and medulla > CN VIII > Internal acoustic meatus > divides:
‧ Vestibular n. > Vestibular ganglion > Sup. and inf. parts > Semicircular ducts, utricle, and saccule
‧ Cochlear n. > Base of cochlea > Modiolus > Base of lamina > Spiral ganglion > Receptors in spiral
organ
Facial nerve [VII] in the temporal bone
Internal acoustic meatus > Facial canal > Geniculate ganglion > Stylomastoid foramen
Branches
Greater petrosal nerve
Facial n. > Preganglionic parasympathetic ff. > Branches from facial n. at geniculate ganglion >
Hiatus for the greater petrosal n. (ant. surface of petrous part of temporal bone) >
Floor of middle cranial fossa > Foramen lacerum > Pterygoid canal > Pterygopalatine ganglion
G61-5
Nerve to stapedius and chorda tympani
Facial n. > Internal acoustic meatus > Facial canal > Posterior wall of tympanic cavity > gives:
‧ Nerve to stapedius > Stapedius m.
‧ Chorda tympani n. > enters middle ear from posterior wall > passes between malleus and incus >
through petrotympanic fissure > Infratemporal fossa > joins lingual n.
Transmission of sound
Sound wave > External acoustic meatus > Tympanic membrane > Handle of malleus (medially) >
Head of malleus (laterally) > Head of incus (laterally) > Long process of incus (medially) >
Stapes (medially) > Base of stapes (medially) > Oval window
Wave of perilymph in scala vestibule > through cochlea > Helicotrema > Scala tympani >
Vibration of basilar membrane > Stimulation of receptor cells in spiral organ >
Secondary tympanic membrane (on round window)
Tensor tympani m. (malleus) and/or stapedius m. (to stapes) dampens the vibration of ossicles.
G61-6
Gross Anatomy, Cranial Nerves
Cranial Nerves
Cranial Nerves
I. Olfactory nerve
II. Optic nerve
III. Oculomotor nerve
IV. Trochlear nerve
V. Trigeminal nerve
VI. Abducent nerve
CN I
VII. Facial nerve
VIII. Vestibulocochlear nerve
IX. Glossopharyngeal nerve
X. Vagus nerve
XI. Accessory nerve
XII. Hypoglossal nerve
Olfactory Nerve
Smell receptors from olfactory epithelium (in nasal cavity)  Olfactory nerves 
through cribriform plate of ethmoid bone  Olfactory bulb (a part of brain)  Olfactory tract
CN II
Optic Nerve
Visual receptors from neural layer of retina  Optic nerve  Optic chiasm  Optic tract 
Lateral geniculate body  Optic radiation  Visual cortex in occipital lobe
CN III Oculomotor Nerve
Midbrain between two cerebral peduncle  Oculomotor nerve  through cavernous sinus 
through superior orbital fissure 
Motor – levator palpebral superioris, sup. rectus, med. rectus, inf. rectus, inf. oblique mm.
Preganglionic parasympathetic fibers  Synapse at ciliary ganglion  Short ciliary nerve  Sphincter
pupillae and ciliary muscles
CN IV Trochlear Nerve
Posterior aspect of midbrain  Trochlear nerve  through cavernous sinus  through superior orbital
fissure  Superior oblique m.
CN V
Trigeminal nerve
From lateral angle of pons (in posterior cranial fossa)  Trigeminal ganglion in middle cranial fossa 
A. Ophthalmic nerve (CN V1)  through superior orbital fissure
1. Lacrimal nerve
a. Sensory – skin of upper eyelid, conjunctiva
b. Carries – parasympathetic fibers from CN VII (facial nerve)
2. Frontal nerve – sensation from upper eyelid, scalp, and forehead
Sensory – supraorbital nerve
Sensory – supratrochlear nerve
3. Nasociliary nerve
Short ciliary nerve
G62-1
Gross Anatomy, Cranial Nerves
Sensory
Postganglionic parasympathetic fibers – from ciliary ganglion, to ciliary muscle and sphincter
pupillae
Postganglionic sympathetic fibers – from superior cervical ganglion, to dilator pupillae
Long ciliary nerve
Sensory – from cornea and iris
(2) Postganglionic sympathetic fibers – from superior cervical ganglion, to dilator pupillae
Infratrochlear nerve
(1) Sensory – from eyelids, conjunctiva, skin of nose, lacrimal sac
Anterior and posterior ethmoidal nerves
Sensory – from mucous membrane of sphenoidal and ethmoidal sinuses  Nasal cavity  Skin
on the bridge of nose (external nasal n.)
B. Maxillary nerve (CN V2)
Infraorbital nerve
a. Sensory to skin and maxillary teeth and gum
Zygomaticotemporal nerve
Sensory
Communicating branch – carrying parasympathetic fibers to lacrimal nerve
Zygomaticofacial nerve
Posterior superior alveolar nerve
Sensory to posterior maxillary teeth, maxillary sinus,
Anterior superior alveolar nerve
a. Sensory to anterior maxillary teeth
C. Mandibular nerve (CN V3)
Nerve to masseter
Nerves to temporalis
Nerve to lateral pterygoid muscle
Nerve to medial pterygoid muscle
Buccal nerve  Sensory to skin on cheek and oral mucosa in cheek
Inferior alveolar nerve 
through mandibular foramen  to mandibular teeth and gum  through mental foramen  Mental
nerve
Mylohyoid n.  Innervates mylohyoid m.
Lingual nerve  joined by chorda tympani  to submandibular ganglion  to tongue
Sensory nerve – general sensation to anterior 2/3 of tongue
Sensory nerve – special sensation for gustation to anterior 2/3 of tongue  Chorda tympani (CN
VII)
Carries preganglionic parasympathetic nerve fibers – from chorda tympani (CN VII)  synapse at
submandibular ganglion  Secretomotor to submandibular and sublingual glands
Auriculotemporal nerve 
sensory to the skin of temporal region
G62-2
Gross Anatomy, Cranial Nerves
carries postganglionic parasympathetic fibers from otic ganglion (from CN IX)  Parotid gland
CN VI Abducent Nerve
Junction of pons and medulla  Abducentnerve  through cavernous sinus 
through superior orbital fissure  Lateral rectus m.
CN VII Facial Nerve
From junction of pons and medulla  Facial nerve (includes nervus intermedius)  through internal
acoustic meatus  Geniculate ganglion (ganglion for taste sensation) 
Greater petrosal nerve (with parasympathetic nerve fibers from nervus intermedius)  on the floor of
middle cranial fossa  through foramen lacerum  under the base of skull 
Joined by deep petrosal nerve (sympathetic fibers from nervous plexus around carotid arteries) 
Nerve of pterygoid canal 
Pterygopalatine ganglion (parasympathetic fibers synapse at there; sympathetic fibers pass through) 
Pterygopalatine nerves  Maxillary nerve  Zygomatic nerve  Zygomaticotemporal nerve 
Communicating branch  Lacrimal nerve  Lacrimal gland
Stapedius muscle
Chorda tympani (with preganglionic parasympathetic nerve fibers from nervus intermedius)  join
lingual nerve  Synapse at submandibular ganglion  Postganglionic parasympathetic fibers 
Submandibular and sublingual glands
Taste buds of anterior 2/3 of tongue  Gustatory sensation  Chorda tympani  Geniculate ganglion
 Facial nerve
Facial nerve  through stylomastoid foramen 
Temporal, zygomatic, buccal, mandibular, and cervical branches  Motor to facial expression muscles
CN VIII Vestibulocochlear Nerve
From junction of pons and medulla  Vestibulocochlear nerve  through internal acoustic meatus 
Vestibular nerve  Vestibular ganglion 
Vestibule  Saccule  Macula  Hair cells
Vestibule  Utricle  Macula  Hair cells
Semicircular canals  Semicircular ducts  Cristae ampullares
Cochlear nerve  Spiral ganglion  Cochlea  Cochlear duct  Organ of Corti  Hair cells
CN IX Glossopharyngeal Nerve
Rootlets from lateral upper medulla  Glossopharyngeal nerve 
Pharyngeal branch (sensory nerve)  to mucosa of pharynx
Tympanic nerve
Preganglionic parasympathetic nerve fibers  Promontory in the middle ear  Tympanic plexus 
Lessor petrosal nerve  on the floor of middle cranial fossa  through foramen ovale  Synapse
at otic ganglion (medial to the mandibular nerve)  Postganglionic parasympathetic fibers join
auriculotemporal nerve (of CN V3)  Secretomotor to parotid gland
G62-3
Gross Anatomy, Cranial Nerves
Sensory fibers  tympanic cavity, auditory tube, mastoid antrum and air cells, inner surface of ear
drum
Carotid sinus branch (sensory nerve)
Stylopharyngeus muscle (motor nerve)
Tonsilar branch (sensory nerve)
Taste sensation and general sensation to posterior 1/3 of tongue (sensory nerve)
CN X
Vagus Nerve
Rootlets from lateral medulla  Vagus nerve  through jugular foramen 
Meningeal branch to dura mater (sensory nerve)
Auricular nerve (sensory nerve)
Pharyngeal branch – to muscles of pharynx and most of soft palate (except tensor veli palatini by CN V3)
Enter carotid sheath to give rise to
Pharyngeal nn. – sensory to valleculae of pharynx (for general sensation and gustation)
Sup. laryngeal nn. – sensory to larynx; motor to cricothyroid muscle
Recurrent laryngeal nn. – motor to intrinsic laryngeal mm.
Cardiac nn. – slow the heart rate
Through diaphragm
Esophageal branches
Gastric branches
Pancreatic branches
Branches to gallbladder
Branches to intestine (Auerbach’s plexus) as far as left colic flexure
http://en.wikipedia.org/wiki/Auerbach's_plexus#cite_note-2
G62-4
Gross Anatomy, Cranial Nerves
CN XI Accessory Nerve
Spinal root from lateral spinal cord  enter posterior cranial fossa through foramen magnum 
Joined by cranial root from lateral medulla  Accessory nerve  through jugular foramen 
Cranial root separates to join vagus nerve  muscle of soft palate, pharynx, larynx, and esophagus
Spinal root supplies trapezius and SCM muscles
CN XII Hypoglossal Nerve
From antero-lateral medulla  through hypoglossal canal  joined by C1 fibers 
Meningeal branch  returns skull through hypoglossal canal  dura mater of posterior cranial fossa
Motor to intrinsic (longitudinal, vertical, horizontal) and extrinsic (hyoglossal, styloglossal, genioglossal)
muscles of tongue
1. C1 fibers descend to form superior root of ansa cervicalis  to geniohyoid and infrahyoid muscles
G62-5
Surface anatomy (pages 1120-1135)
Head and neck surface anatomy
Skeletal landmarks
Neurological examination
General body health
Anatomical position of the head and major landmarks
Frankfort plane – inf. margin of orbit, zygomatic arch, and sup. margin of external acoustic meatus
Head of mandible
Zygomatic arch
Mastoid process – sup. end of SCM m.
External occipital protuberance
Vertex
Scalp – anterior to vertex by CN V; posterior to vertex by cervical spinal nn.
Visualizing structures at the CIII/CIV and CVI vertebral levels
CIII/CIV – bifurcation of common carotid a., upper margin of thyroid cartilage
CVI – pharynx to esophagus; larynx to trachea; inferior margin of cricoid cartilage
How to outline the anterior and posterior triangles of the neck
Anterior triangle – inf. margin of mandible; medial border of SCM m.; midline of neck
Airway, digestive tract, nerves and vessels b/w head and thorax, thyroid and parathyroid glands
Posterior triangle – middle 1/3 of clavicle; lateral border of SCM m.; ant. border of trapezius
Nerves and vessels to and from upper limb
How to locate the cricothyroid ligament
Cricothyroid ligament (or cricovocal membrane, cricothyroid membrane) – for emergency penetration
Sup. > thyroid notch > thyroid prominence (more prominent in man) > criothyroid membrane >
arch of cricoid cartilage > Inf.
Structures on it: pyramidal lobe of thyroid gland
How to find the thyroid gland
Two lobes in lower anterior triangle; isthmus crosses on midline of trachea
Estimating the position of the middle meningeal artery
Maxillary a. > through f. spinosum > within dura mater >
Anterior br. > under pterion > damage to form extradura hematoma
Major features of the face
Openings: orbit, nasal cavities, and oral cavity
 Palpebral fissures – with orbicularis oculi mm. by CN VII
 Oral fissure – with orbicularis oris m. by CN VII
 Nares – anterior apertures of nasal cavities
Philtrum –
Sensory innervation – by CN V brr.



CN V1 – test on forehead
CN V2 – test on anterior cheek
CN V3 – test on skin on anterior body of mandible
G63-1
The eye and lacrimal apparatus
Sclera, cornea, iris, and pupil
Palpebral fissures, palpebral commissures
Lacrimal caruncle, lacrimal fold, lacrimal lake,
Lacrimal apparatus – lacrimal gland, and ducts and channels for drainage to nasal cavities
Lacrimal gland – in the depression under the lateral roof of orbit
Tears in lacrimal lake drain through:
lacrimal puncta (on lacrimal papillae) > into lacrimal canaliculi > lacrimal sac > nasolacrimal duct > nasal
cavity
External ear
Auricle –
Helix, lobule >
Triangular fossa, scaphoid fossa (depression) >
Antihelix, antitragus, intertragic incisure, tragus >
Cymba conchae, concha >
External acoustic meatus
Pulse points
1. Carotid pulse (common or ext. carotid a.) – one of strongest pulse points in body;
 posterolateral of larynx for common carotid a.,
 lateral of pharynx b/w hyoid and superior margin of thyroid of external carotid a.
2. Facial pulse (facial a.) – inferior border of mandible at anterior margin of masseter
3. Temporal pulse (superficial temporal a.) – anterior to ear; posterosuperior to TMJ
4. Temporal pulse (anterior br. of superficial temporal a.) – posterior to zygomatic process of frontal bone
G63-2