Head and neck

Arteries

1. Blood supply of face:

Image result for External carotid artery branches

  • External carotid artery branches ^^
  • Ophthalmic artery branches: supratrochlear, supraorbital

 

2. Ophthalmic artery:

  • 1st branch of internal carotid artery
  • Through optic canal
  • Runs in medial wall of orbit
  • Branches:
  1. Lacrimal
  2. Central retinal
  3. Supratrochlear
  4. Supraorbital

 

3. Maxillary artery:

  • Branch of external carotid artery, arises behind neck of mandible

1st part (mandibular):

  • Passes between mandible ramus and sphenomandibular ligament
  • Branches:
  1. Deep auricular
  2. Anterior tympanic
  3. Inferior alveolar
  4. Middle meningeal
  5. Accessory meningeal

2nd part (pterygoid):

  • Passes between 2 heads of lateral pterygoid muscle and enters pterygoid fossa
  • Branches:
  1. Masseteric
  2. Deep temporal
  3. Pterygoid
  4. Buccal

3rd part (pterygomaxillary):

  • Lies in pterygopalatine fossa
  • Branches:
  1. Sphenopalatine artery
  2. Greater and lesser palatine arteries
  3. Posterior superior alveolar artery
  4. Pharyngeal artery
  5. Infraorbital artery

 

4. Facial artery:

  • Emerges in carotid triangle from external carotid artery (ECA)
  • Deep to mandible ramus
  • Superficial to masseter and buccinator
  • Ascends lateral nose
  • Becomes angular artery
  • Branches:
  1. Superior labial
  2. Inferior labial
  3. Lateral nasal
  4. Angular

 

5. Subclavian artery:

  • Right one arises from brachiocephalic artery, left one arises from arch of aorta
  • It is divided into 3 parts as it passes posterior to anterior scalene muscle
  • Branches:
  1. 1st part – Vertebral, internal thoracic, thyrocervical
  2. 2nd part – Superior intercostal, deep cervical
  3. 3rd part – Dorsal scapular
  • Continues as axillary artery at border of 1st rib

 

6. Common carotid artery:

  • Right from brachiocephalic trunk, left from arch of aorta
  • Bifurcates into ECA and ICA at superior border of thyroid cartilage

 

7. External carotid artery:

  • Formed from common carotid artery
  • At upper border of thyroid cartilage
  • Outside carotid sheath
  • Posterior to ramus of mandible
  • Terminates as superficial temporal and maxillary artery

 

8. Vertebral artery:

  • From subclavian artery 1st part
  • Through vertebral triangle
  • Ascend in transverse foramina C6-C1
  • Enter cranial cavity via foramen magnum
  • Joins other side’s vertebral artery to form basilar artery at base of pons

Veins

1. Venous drainage of face

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2. Facial vein:

  • Tributaries: Supraorbital and supratrochlear drain into angular vein
  • Becomes facial vein
  • Superficial to masseter, buccinator and mandible
  • Joins anterior division of retromandibular vein
  • To form common facial vein
  • Drains into IJV

 

3. External jugular vein (EJV):

  • Formed from retromandibular vein, posterior division and posterior auricular vein
  • Forms at angle of mandible
  • Pierce deep fascia
  • Drain into subclavian vein

 

4. Internal jugular vein (IJV):

  • Formed from sigmoid sinus and inferior petrosal sinus
  • Through jugular foramen
  • Runs in carotid sheath
  • Unites with subclavian vein to form brachiocephalic vein
  • Tributaries: Common facial, lingual, pharyngeal, superior and middle thyroid veins

5. Subclavian vein:

  • Continuation of axillary vein from border of 1st rib
  • Anterior to scalenus anterior muscle
  • Joins IJV and EJV to form brachiocephalic vein

Nerves

1. Nerve supply to face:

  • Motor – facial nerve branches
  • Sensory – trigeminal nerve and nerves C2, C3, C4

 

2. Inferior alveolar nerve:

  • Branch of V3
  • Gives off a branch – mylohyoid nerve (mylohyoid and anterior diagastric muscle)
  • Between mandible ramus and medial pterygoid muscle
  • Enters mandible foramen, through mandible canal
  • Through inferior dental plexus
  • Gives off a mental nerve (at mandibular 2nd premolar) which exits via mental foramen (sensory to chin and lower lip)
  • Continues as mandibular incisive nerve to innervate mandibular canines and incisors

Clinicals:

  • Inferior alveolar nerve block – anesthesia near mandibular foramen
  • Injury – 3rd molar removal, dental implants, root canal

 

3. Lingual nerve:

  • Branch of V3
  • Chorda tympani nerve (of facial nerve) joins lingual nerve
  • Between mandible ramus and medial pterygoid muscle
  • Inferior to 3rd molar
  • Runs between hyoglossus muscle and deep part of submandibular gland
  • Crosses lateral to medial over Wharton’s duct
  • Runs along tip of tongue becoming sublingual nerve, lying beneath mucous membrane

Clinical: 3rd molar surgery – injury to nerve

 

4. Cervical plexus:

Anterior rami C1-C4 – in carotid triangle

Image result for cervical plexus

 

5. Gustatory pathway:

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Waldeyer’s ring

Image result for waldeyer's ring

Palatine tonsils:

  • Location: Between palatoglossus and palatopharyngeus folds
  • Relations:
  1. Anterior – palatoglossus fold
  2. Posterior – palatopharyngeus fold
  3. Superior – soft palate
  4. Inferior – tongue
  5. Lateral – superior constrictor
  • Blood supply:

Image result for palatine tonsils blood supply

  • Nerve: Glossopharyngeus nerve, lesser palatine nerve (V2)

Clinicals: Tonsillitis, tonsilectomy


 

Temporomandibular joint (TMJ)

Lateral pterygoid muscle attatches to TMJ capsule – slide forward movement

Classification: Synovial modified hinge

Lined by: Fibrocartilage

Articular surfaces: Condyle, mandibular fossa and articular tubercle of squamous temporal

Image result for mandibular fossa

 

Stability factors:

Static:

  • Mandibular fossa and posterior glenoid tubercle
  • Articular disc – attaches to internal surface of joint capsule, dividing it into superior and inferior cavity
  • Condyle head more convex antero-posteriorly than medial to lateral
  • Lateral pole more anterior than medial
  • Ligaments:
  1. Lateral ligament – from articulating eminence to posterior condyle, prevents extreme retrusion
  2. Lateral and medial collateral ligament
  3. Sphenomandibular ligament – from sphenoid spine to lingula, prevents extreme protrusion
  4. Stylomandibular ligament – from styloid process to angle of mandible

 

Image result for TMJ ligaments

 

Dynamic: Muscles of mastication

Blood supply: Superficial temporal and masseteric arteries

Nerve supply: Auriculotemporal and masseteric

Movements: Rotation, Protraction

Relations:

  • Anterior – lateral pterygoid muscle
  • Posterior – parotid gland
  • Lateral – parotid gland
  • Medial – spine of sphenoid
  • Superior – middle cranial fossa
  • Inferior – maxillary artery

Glands

(I) Lacrimal gland:

Blood supply: Lacrimal artery from opthalmic artery

Nerve supply:

Image result for innervation of lacrimal gland


 

(II) Parotid gland:

Relations:

  • Superior – zygomatic arch
  • Inferior – mandible angle
  • Anterior – masseter muscle
  • Posterior – sternocleidomastoid muscle (SCM)
  • Roof – skin and fascia
  • Floor – masseter, SCM, mandible ramus

Stenson’s duct course: Anterior to masseter, pierce buccinator, open in vestibule next to 2nd maxillary molar

Pierced by: Superficial temporal artery, retromandibular vein, facial nerve

Blood supply: Superficial temporal artery

Venous: Retromandibular vein

Nerve supply: 

Image result for nerve supply parotid gland

  • Parasympathetic: Lesser petrosal nerve
  • Sympathetic: Superior cervical ganglion

Lymphatic drainage: Posterior and preauricular lymph nodes

Type of secretion: Serous

Clinicals:

  • Parotid gland tumor
  • Parotiditis – inflammation
  • Mumps

 

(III) Submandibular gland:

Location: Submandibular triangle

Relations:

  • Superior – mylohyoid line
  • Inferior – diagastric tendon
  • Anterior – mental foramen
  • Posterior – mandible angle
  • Medial – root of tongue
  • Lateral- masseter and mandible

Wharton’s duct course: Through 3 muscles (mylohyoid, hyoglossus, genioglossus) ⇒ crossed by lingual nerve ⇒ opens near frenulum

Nerve supply: 

  • Parasympathetic: Vasodilation
  • Sympathetic: Vasoconstrict, therefore enzyme rich mucous

Image result for submandibular gland nerve supply

Lymphatic drainage: Submandibular lymph nodes, which drain to jugulodiagastric lymph nodes

Type of secretion: Serous and mucous (seen as demilunes in histology)

Clinicals:

  • Submandibular excision – damage lingual and facial nerve
  • Calcified stones – due to ascending duct, serous and mucous secretions, and it’s a long duct

 

(IV) Sublingual gland:

Location: Sublingual fossa above mylohyoid line

Relations:

  • Superior – mucous membrane of mouth
  • Inferior – mylohyoid muscle
  • Posterior – submandibular gland
  • Medial – genioglossus muscle
  • Lateral- sublingual fossa

Blood supply, venous drainage, nerve supply and lymph nodes – same as submandibular gland

Type of secretion: Mucous – sublingual papilla

Clinicals:

  • Ranula – mucous cysts in floor of mouth

 

(V) Thyroid gland:

Location: Anterior neck, below laryngeal prominence

Extent: C5-T1

Relations:

  • Anterior – sternohyoid, sternothyroid
  • Posterior – trachea
  • Superior – cricothyroid cartilage
  • Inferior – 5 tracheal rings
  • Medial – esophagus
  • Lateral – carotid sheath

Blood supply: Superior, middle, inferior thyroid artery and vein

Nerves:

  • Sympathetic: Cervical sympathetic ganglions (superior, middle, inferior)
  • Parasympathetic: Vagus nerve

Lymphatics: Pretracheal. paratracheal and prelaryngeal lymph nodes

Image result for pretracheal lymph nodes

 

Clinicals:

  • Goiter – enlarged thyroid gland
  • Thyroidectomy – surgical removal
  • Tracheotomy – forming an opening into trachea due to sudden obstruction of vital airways
  • Laryngoscopy

 


Muscles

(I) Extraocular muscles:

Image result for extraocular muscles and levator palpebrae superioris

Blood supply: Ophthalmic artery

Nerve supply: Oculomotor, Trochlear (superior oblique), Abducens (lateral rectus)


 

(II) Muscles of mastication:

Image result for muscles of mastication

 

Image result for muscles of mastication origin and insertions

 


 

(III) Suprahyoid muscles:

Image result for suprahyoid muscles

 

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(IV) Infrahyoid muscles:

Image result for infrahyoid muscles


 

(V) Sternocleidomastoid (SCM):

  • Origin: 2 heads – manubrium, medial 1/3 clavicle
  • Insertion: mastoid process
  • Innervation: CN 11
  • Action: Turn head opposite side, raise thorax
  • Relations:
  1. Anterior – platysma muscle
  2. Posterior – carotid sheath
  3. Medial – ansa cervicalis
  4. Lateral – subclavian artery

 

(VI) Scalenus anterior:

  • Origin: Transverse process C3-C6
  • Insertion: 1st rib, scalene tubercle
  • Innervation: Anterior rami C4-C6
  • Relations:
  1. Anterior – SCM, subclavian vein
  2. Posterior – 2nd part subclavian artery, brachial plexus
  3. Medial – 1st part subclavian artery
  4. Lateral – 3rd part subclavian artery, brachial roots

Clinicals: Scalenus anterior syndrome – hypertonic muscle, compresses structures


Spaces

(I) Orbit:

Boundaries:

Image result for orbit boundaries

Foramens/fissures and their contents:

Related image

Orbit contents: Extraocular muscles and ciliary ganglion


 

(II) Temporal fossa:

Image result for temporal fossa boundaries


 

(III) Infratemporal fossa:

 

Related image

 

Contents: Lateral and medial pterygoid muscles, maxillary artery, mandibular nerve, otic ganglion


 

(IV) Pterygopalatine fossa:

Image result for pterygopalatine fossa boundaries

 

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Clinicals: Ligate sphenopalatine artery to stop nose bleeding


 

(V) Neck triangles:

(A) Anterior neck triangles

Boundaries:

14

 

Contents:

Image result for neck triangles

 

(B) Posterior neck triangles

Boundaries:

Image result for anterior triangle of neck boundaries

  • Roof: Investing fascia
  • Floor: Anterior, middle and posterior scalene muscles

 

Image result for occipital and subclavian triangles

 

Contents:

  1. Occipital: Brachial roots, cervical plexus, occipital artery
  2. Subclavian: Subclavian artery and vein, EJV, brachial plexus trunks

 

(VI) Interscalene triangle:

  • Boundaries: Anterior scalene, middle scalene, 1st rib
  • Contents: Subclavian artery, brachial plexus roots

 

(VII) Suboccipital triangle:

Boundaries:

Image result for Suboccipital triangle

Contents: Vertebral artery, suboccipital venous plexus

Clinicals: Angiography of circle of Willi’s


 

Nasal cavity:

 

Image result for nasal cavity

 

Extent: Vestibule to nasopharynx

3 parts: Vestibule, olfactory region, respiratory region

Functions: 

  • Humidify air – rich vascular supply
  • Conchae slow down air
  • Prevent pathogens
  • Smell
  • Drain paranasal sinus

Boundaries:

  • Superior – ethmoid and sphenoid bone
  • Inferior – palatine bone
  • Medial – septa
  • Lateral – conchae

 

Below superior, middle and inferior conchae are meati (openings)

Image result for sphenoethmoidal recess

Openings in the meati:

  • Above superior conchae/ sphenoethmoidal recess – Sphenoidal sinus
  • Superior meatus – Posterior ethmoidal sinus
  • Middle meatus – Frontal, maxillary and anterior ethmoidal sinus
  • Inferior meatus – Auditory tube, nasolacrimal duct

Other openings:

  • Cribriform plate – olfactory nerves
  • Sphenopalatine foramen (connects pterygopalatine fossa) – sphenopalatine artery, nasopalatine nerve
  • Incisive canal (connects oral cavity) – nasopalatine nerve to oral cavity

Blood supply:

  • Internal carotid artery: Anterior and posterior ethmoidal via cribriform plate
  • External carotid artery:
  1. Maxillary artery – Sphenopalatine, greater palatine
  2. Facial artery – Superior labial, lateral nasal

Venous: Ophthalmic vein, angular vein, sphenopalatine vein

Nerves:

  • Smell – olfactory
  • General sensory – nasopalatine, nasociliary (V2)

 

Clinicals: Spread of respiratory infection to ear


 

Paranasal sinuses:

 

Image result for paranasal sinus

  • Air filled extensions of nasal cavity
  • Reduce weight of skull
  • Humidify air
  • Are paired
  • Are mucous lined

 

20

Clinicals:

  • Sinusitis
  • Inflammation of maxillary sinus – tooth ache
  • Rhinitis – inflamed nasal mucosa
  • Epistaxis – nose bleed (trauma or hypertension)

 

Tongue:

4 types of papillae:

Image result for tongue papilla

  1. Filiform – all over the tongue, only type that contain no taste buds
  2. Fungiform – mushroom shaped, concentrated on tip of tongue
  3. Foliate – found on postero-lateral surface of tongue
  4. Circumvallate – 12 to 14, anterior to sulcus terminalis, Von Ebner’s glands open in it

 

Extrinsic muscles:

Image result for extrinsic muscles of tongue

 

Image result for extrinsic muscles of tongue and their function

 

Intrinsic muscles:

Related imageRelated image

 

Blood supply: Lingual artery and vein

Nerve supply:

  • Taste: Anterior 2/3 chorda tympani nerve, Posterior 1/3 glossopharyneal nerve
  • General sensation: Anterior 2/3 Lingual nerve (V3), Posterior 1/3 glossopharyneal nerve
  • Motor:  Hypoglossus nerve, except palatoglossus muscle which is supplied by vagus nerve

Lymphatic drainage: Superior deep cervical, inferior deep cervical, submandibular, submental lymph nodes

Image result for lymphatic drainage of tongue

 

Clinicals:

  • Tongue tie
  • Cancer
  • Halitosis – bad breath
  • Oral thrush

Hard palate and soft palate

Soft palate muscles:

Image result for soft palate muscles table

Blood supply:

Hard palate: Greater palatine artery (from descending palatine)

Soft palate:

  • Greater/ lesser palatine (from maxillary artery)
  • Ascending palatine (from facial artery)
  • Ascending pharyngeal (from ECA)

Veins: Drain into pterygoid venous plexus

Nerves: 

Hard palate:

  • Greater palatine – mucosa of posterior hard palate (from pterygopalatine ganglion, descends through greater palatine foramen with greater palatine artery)
  • Nasopalatine – anterior mucosa (through incisive formen)

Soft palate:

  • Pharyngeal plexus via vagus nerve
  • Except tensor veli palatini – medial pterygoid nerve (V3)
  • Sensory – Lesser palatine nerve

Lymphatic drainage:

Hard palate: Submandibular, superior deep cervical nodes

Soft palate: Retropharyngeal, superior deep cervical nodes

 

Clinicals:

  • Cleft palate
  • Palatal abscesses
  • Cleft uvula
  • Pimples on hard palate

Pharynx

Extent: Base of skull to C6

Layers:

  1. Buccopharyngeal fascia
  2. Muscular layer – outer circular, inner longitudinal
  3. Pharyngobasilar fascia
  4. Submucosa
  5. Mucosa
  6. Surface epithelium

Muscles:

Image result for constrictor muscles of pharynx

18

 

Blood supply:

Image result for pharynx blood supply

 

Nerve:

Motor:

  • Glosopharyngeal – Stylopharyngeus muscle
  • Vagus – Rest of pharynx muscles

Sensory:

  • Nasopharynx – Maxillary (V2)
  • Oropharynx – Glossopharyngeal
  • Laryngopharynx – Vagus

Lymphatics: Upper and lower deep cervical lymph nodes, retropharyngeal nodes

Clinicals: 

  • Tonsillitis
  • Pharyngeal diverticulum – cricopharyngeus does not relax, food accumulates, dysphagia
  • Tumors – dysphagia, dysphonia

 

Nasopharynx, oropharynx, laryngopharynx

 

Image result for pharynx divisions

 

19


Larynx

 

Image result for larynx

  • Phonation
  • Cough reflex
  • Protect respiratory tract

Extent: C3-C6

Relations:

  • Anterior – infrahyoid muscles
  • Posterior – trachea
  • Lateral – thyroid lobes

Made of 6 cartilages: (all are hyaline cartilage except epiglottis)

Single:

  • Thyroid – has laryngeal prominence
  • Cricoid – encircles completely at C6
  • Epiglottis – elastic cartilage

Paired:

  • Arytenoid
  • Corniculate
  • Cuneiform

Ligaments/membranes:

Extrinsic:

  • Thyrohyoid membrane – pierced by internal laryngeal nerve and superior laryngeal vessels
  • Median cricothyroid ligament
  • Cricotracheal ligament

Intrinsic:

  • Cricothyroid/vocal ligament
  • Quadrangular ligament

NB: Vocal opening – Rima glottidis

Blood supply:

  • Superior laryngeal artery(from superior thyroid artery) – runs with internal laryngeal nerve
  • Inferior laryngeal artery(from inferior thyroid artery) – runs with recurrent laryngeal nerve

Venous:

  • Superior laryngeal – drains in superior thyroid
  • Inferior laryngeal – drains in inferior thyroid

Nerves:

Sensory:

  • Infraglottis – Recurrent laryngeal
  • Supraglottis – Internal laryngeal

Motor:

  • Cricothyroid muscle – External laryngeal
  • All other muscles – Recurrent laryngeal

Sympathetic: Middle and inferior cervical sympathetic ganglia

 

Clinicals:

  • Cricothyroidotomy- Make temporary airway
  • Laryngitis
  • Laryngectomy
  • Laryngoscopy
  • In puberty, boy’s cartilage enlarge, vocal folds become thicker
  • Old age – ligament and cartilage ossify


Others

1. Horner’s syndrome:

Image result for Horner's syndrome:


 

2. Deep fascia of neck:

13


 

3. Structures in midline of neck:

Hyoid bone ⇒ Thyrohyoid membrane ⇒ Thyroid cartilage ⇒ Cricothyroid membrane ⇒ Cricoid cartilage ⇒ Cricotracheal ligament ⇒ Tracheal rings

Image result for cartilages in midline of neck

NB: Internal laryngeal artery and superior laryngeal vessels pierces thyrohyoid membrane


 

4. Carotid body and carotid sinus:


 

5. Parts of mandible:

Image result for parts of mandible


 

6. External and internal auditory meatus:

21

EAM to tympanic cavity:

  • Blood supply: Posterior auricular, superficial temporal
  • Nerve: Great auricular, auriculotemporal

 

IAM:

  • Blood supply: ascending pharyngeal
  • Nerve: Glossopharyngeal

 

Clinicals:

  • Otitis – ear inflammation
  • Mastoiditis – middle ear infection

 

These are summarized notes from various sources, mainly TeachMeAnatomy and Wikipedia

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