Head and Neck Anatomy (1-3) Flashcards
State the superior and inferior border of the neck
SUPERIOR
Inferior border of mandible
Angle of mandible
Mastoid process
Superior nuchal line (for attachment of muscles at back of neck)
External occipital protuberance (EOP)
INFERIOR
Thoracic inlet / Superior thoracic aperture (STA)
Anterior: Manubrium + 1st costal cartilage
Posterior: T1 vertebra
Lateal: 1st rib
State the 3 cartilages located in neck from superior to inferior.
State any boney landmarks.
- HYOID BONE
- THYROID CARTILAGE - upper border is C3/4 (bifurcation of common carotid A into ICA and ECA)
- CRICOID CARTILAGE - lower border is C6 (superior end of oesophagus and trachea)
State the function of cricothyroid ligament and cricothyroid muscle
CRICOTHYROID LIGAMENT - helps to stabilise and anchor thyroid cartilage to cricoid cartilage
CRICOTHYROID MUSCLE - pulls thyroid cartilage downwards to tense vocal folds and form higher pitch sounds
Name the nerve suppllying cricothyroid. Name the nerve supplying all other structures of larynx
cricothyroid - external laryngeal n
all others - recurrent laryngeal n
both nerves are branches of vagus n (CN X)
State the borders of the anterior triangle of neck
Superior: Inferior margin of mandible
Medial: Midline of neck
Lateral: Anterior margin of SCM
State the borders of the posterior triangle of neck
Inferior: Clavicle
Medial: Posterior margin of SCM
Lateral: Anterior margin of trapezius
State the 3 incisions to be made in dissection of neck
- midline incision - from chin to suprasternal notch
- lateral incision 1 - lower border of mandible to mastoid processes
- lateral incision 2 - suprasternal notch along clavicle to shoulder joints
Label the structures in the neck
Name the 3 layers involved in the deep fascia of the neck.
State the clinial significance of each layer.
(1) INVESTING LAYER
- Provides protection to structures in neck
- Prevents spread of infection
- Lubrication → enables structures in the neck to move and pass over one another during swallowing
(2) PRETRACHEAL LAYER
- Encloses thyroid gland and laterally fuses with carotid sheath
(3) PREVERTEBRAL LAYER
- Encloses the prevertebral muscles and vertebra
State the 3 structures enclosed by the carotid sheath
- internal jugular V
- common carotid A
- CN X (vagus N)
State the contents of the prevertebral layer
- sympathetic trunk - superior, middle and inferiro cervical ganglion (SCG commonly used for sympathetic innervation of stuctures in head)
- phrenic nerve
- brachial plexus (brachial plexus block done above clavicle behind SCM)
State the veins that are in union to form the EXTERNAL JUGULAR VEIN
- posterior division of retromandibular V
- posterior division of auricular V
Name and label the muscles in this diagram
State the 4 branches of the cervical plexus (C1-C4)
- lesser occipital
- great auricular
- transverse cervical
- supraclavicular
Name the 4 infrahyoid (strap) muscles
State the motor innervation of these muscles
- omohyoid
- sternohyoid
- sternothyroid
- thyrohyoid
Innervtion = ansa cervicalis (C1-C4) + sympathetic trunk (mainly superior cervical ganglion)
State the actions of platysma
- Pulls down the mandible → opens mouth
- Pulls corners of lips out to the side and down → frown
State the vessels located anterior and posterior and BETWEEN the scalenius anterior and medius.
anterior to SA/SM = subclavian V
posterior to SA = subclavian A
between SA and SM = brachial plexus + subclavian A
State the action of ____ on cervical vertebrae:
1. prevertebral muscles + SA + SM =
2. postvertebral muscles - SA - SM =
- prevertebral muscles + SA + SM = flexion of cervical vertebrae
- postvertebral muscles - SA - SM = extension of cervical vertebrae
State the innervation of SCM and trapezius.
State a positive test for lesion of the nerve innervating these muscles.
Innervation = CN XI (Spinal accessory N)
Positive test for inability to lift shoulders + medially rotate face when force applied due to weak trapezius
State the 8 branches of ECA (external carotid A)
State the 5 branches of ICA (internal carotid A)
EXTERNAL CAROTID A (Sister Lucy’s Powdered Face Often Attracts Medical Students)
1. Superior thyroid A
2. Lingual A
3. Posterior auricular A
4. Facial A
5. Occipital A
6. Ascending Pharyngeal A
7. Maxillary A
8. Superficial temporal A
INTERNAL CAROTID A (One Punch And A Man)
1. Opthalmic A
2. Posterior communicating A
3. Anterior choroidal A
4. Anterior cerebral A
5. Middle cerebral A
State the levels at which anastomosis occurs in ECA.
- Between right and left superior thyroid A
- Between right and left facial A
- Between right and left occipital A
- Between right and left superficial temporal A
- Between ICA and ECA
State the vessels involved in blood supply and drainage to and away from thyroid gland (State any anastomosis that occurs).
State the innervation of thyroid gland.
Blood supply = superior thyroid A + inferior thyroid A + thyroid ima A
- Between R + L STA
- Betwen R + L ITA
- Between branches of STA and LTA
Blood drainage = superior thyroid V + middle thyroid V (STV and MTV drain into IJV -> brachiocephalic V) + inferior thyroid V (drains into brachiocephalic V directly)
- Between R + L STV
- Between R + L ITV
- Between branches of STV and ITV
Innervation:
- Sympathetic - ANS (sympathetic trunk - mainly superior cervical ganglion)
- Parasympathetic - CNX (vagus N) –> superior laryngeal N + recurrent laryngeal N
State the bones and structures in the skull
State the layers of the skull
- Skin
- Connective tissue
- Aponeurosis
- Loose areolar tissue
- Pericranium
- Skull bone
- Dura mater
- Subdural space
- Arachnoid mater
- Subarachnoid space
- Pia mater
- Brain parenchyma / Cerebral cortex
State the significance of EMISSARY VEINS.
emissary veins are the only vessels that communicate between intracranial and extracranial space
- has NO VALVES leading to bidirectional blood flow –> blood pools in cranial cavity –> raised ICP
- infection can spread inwards from extracranial space
State the vessels that supply and drain blood from the scalp.
Blood supply = mainly external carotid A + minorly internal carotid A (opthalmic A)
Blood drainage = dura venous sinuses → internal jugular vein → superior vena cava
State the vessels involved in blood drainage of the face
pterygoid plexus of veins –> maxillary veins –> retromandibular vein –> IJV –> SVC
State the order of the sinuses in CONFLUENCE OF SINUSES
superior saggital sinus + transverse sinus (from inferior saggital sinus) + occipital sinus –> confluence of sinuses –> transverse sinus –<> sigmoid sinus –> IJV
State the contents in the cavernous sinus.
State which structure is most at risk of compression in the presence of a pituitary tumour in the cavernous sinus.
Contains
1. internal carotid A (ICA)
2. CN III - oculomotor N
3. CN IV - trochlear N
4. CN V1 and V2 (opthalmic and maxillary divisions of trigeminal N)
5. CN VI - abducens N
CN VI (abducens N) is most at risk of compression in the presence of a pituitary tumour.
State the 4 branches of the MAXILLARY ARTERY
- infra-orbital A (exits via infra-orbital foramen)
- buccal A
- mental A (exits via mental foramen)
- middle meningeal A (enters cranial cavity through spinosum)
Label the facial muscles
Note: Masseter is not a facial muscle
State the sphincteric and levator facial muscles
State innervation of muscles of the face (state branches if relevant).
SPHINCTERIC:
- orbicularis oris
- orbicularis oculi
LEVATOR
- levator palpebrae superioris
- levator labi superioris
- levator anguli superioris
- depressor anguli oris
- depressor labi inferioris
- zygomatic major and minor
Innervation = CNVII (facial N) for all muscles of face except levator palpebrae superioris which is innervated by CN III (oculomotor N)
- Branches: Temporal, zygomatic, buccal, marginal mandibular, cervical
- Innervation of levator palpebrae superioris = CN III (oculomotor N)
State the 4 muscles of mastication.
State the innervation of these muscles.
State the blood supply and drainage of these muscles.
(1) Temporalis - deep temporal A
(2) Masseter - masseteric A
(3) Medial + (4) Lateral pterygoid - pterygoid branches
Innervation = CN V3 (mandibular division of trigeminal N) - supplies structures derived from 1st pharyngeal arch
Blood supply = maxillary A (Branch of ECA)
Blood drainage = pterygoid venous plexus –> maxillary V –> IJV (internal jugular V)
State the sensory innervation of the skull and scalp.
State the motor innervation of the skull and scalp
Sensory innervation = CN V (trigeminal N) - opthalmic, maxillary and mandibular divisions
Motor innervation = CN VII (facial N) - temporal, zygomatic, buccal, mandibular, cervical
State the motor innervation of the infrahyoid (strap) muscles.
Innervation = Ansa cervicalis (C1-C4) for all strap muscles except thyrohyoid
- Thyrohyoid muscle innervated by C1 + CNXII (hypoglossal N)
Name the 4 suprahyoid muscles
- digastric muscles
- stylohyoid
- mylohyoid
- geniohyoid
State the innervation (parasympathetic, sympathetic, sensory) of parotid gland.
State the vessels involved in blood supply and blood drainage of parotid gland.
INNERVATION:
Parasympathetic - CNIX (glossopharyngeal N)
Sympathetic - Superior cervical ganglion (sympathetic trunk)
Sensory - Mandibular division of CN V - Trigeminal N
Blood supply = External carotid A
Blood drainage = Retromandibular V
CNVII does not innervate parotid gland but will pierce the parotid gland after exiting from stylomastoid foramen
Link each histology side to
1. parotid gland
2. sublingual gland
3. submandibular gland
State if each slide is serous, mixed or mucinous
When does caput succedaneum (subcutaneous hematoma) occur? Between which layers is the hematoma located?
**CAPUT SUCCEDANEUM **
- Occurs secondary to vacuum-asisted delivery
- Occurs between cutaneous tissue and aponeurosis
State the muscles innervated by CN V - trigeminal N (V3)
MUSCLES OF MASTICATION
- temporalis
- masseter
- medial and lateral pterygoid muscles
TENSOR TYMPANI
TENSOR VELI PALITINI
ANTERIOR BELLY OF DIGASTRIC (suprahyoid)
MYLOHYOID (suprahyoid)
State the 2 layers in the dura mater and 3 dural folds.
LAYERS
1. Endosteal layer - lines the inner surface of the bones of the cranium
2. Meningeal layer - lines the endosteal layer in cranial cavity
DURAL FOLDS
1. Falx cerebri - longitudinal fissure separating the 2 hemispheres attached to cribiform plate
2. Tentorium cerebelli - transverse fissure separating occipital lobe from cerebellum
3. Falx cerebelli
State the 3 main cerebral arteries and the parts of the brain they supply.
Does blood supply to the brain only occur through cerebral arteries?
- Anterior cerebral A - supplies anteromedial portion of cerebral hemispheres including medial frontal lobes and superior parietal lobes
- Middle cerebral A - supplies lateral surface of brain including motor and sensory cortices for face and UL
- Posterior cerebral A - supplies medial and inferior parts of the occipital lobe and inferomedial parts of temporal lobe responsible for visual and some memory processing
Vertebral A also contribute some blood supply to the brain.
State the vessels involved in blood drainage from scalp and skull.
- DURAL VENOUS SINUSES (namely = superior saggital sinus, inferior saggital sinus, straight sinus, transverse sinus, sigmoid sinus) –> internal jugular vein –> brachiocephalic vein –> superior vena cava
- superficial veins
- deep veins
Name the connections between
1. lateral and 3rd ventricle
2. 3rd and 4th ventricle
Lateral - 3rd ventricle connection = interventricular foramen (of monro)
3rd - 4th ventricle connection = cerebral aqueduct (of sylvius)
Name the 3 cranial fossas. State the structures that divide the cranial cavity into the fossas.
Label the foramen in cranial cavity.
Name the structures important in the cranial cortex
Name the foramen in the cranial cavity. State the structures in each foramen.
