General oto neck space anatomy

Question 1

What are the two primary fascia networks of the

neck?

Answer 1

Superficial cervical fascia and the deep cervical fascia

Question 2

Describe the anatomy of the superficial cervical

fascia.

Answer 2

It lies just deep to the dermis and superficial to the deep
cervical fascia. It extends from the zygoma to the clavicle
and envelops the platysma and muscles of facial expression.

Question 3

Describe the anatomy of the deep cervical fascia.

Answer 3

It is composed of the superficial (investing), middle (visceral
and muscular), and deep (prevertebral and alar) layer. The
carotid sheath fascia is created by all three layers of the
deep cervical fascia.

Question 4

Describe the anatomy of the superficial (investing)

layer of the deep cervical fascia.

Answer 4

It surrounds the neck and inserts superiorly at the nuchal
ridge, mastoid, zygoma, and mandible and inferiorly at the
clavicles, sternum, scapula, and acromion. It envelops the sternocleidomastoid muscle, trapezius, muscles of masti-
cation, submandibular glands, and parotid gland. Inferiorly, its manubrial insertion splits to form the suprasternal space
of Burns.

Question 5

Describe the anatomy of the middle (visceral and

muscular) layer of the deep cervical fascia.

Answer 5

It extends superior to the cranial base and inferiorly to the
upper mediastinum. It is subdivided into the muscular and

visceral layers. The muscular division surrounds the infra-
hyoid strap muscles; the visceral portion surrounds the pharyngeal constrictors, esophagus, trachea, and thyroid
and creates the buccopharyngeal fascia. Both divisions
contribute to the carotid sheath.

Question 6

Describe the anatomy of the deep (prevertebral

and alar) layer of the deep cervical fascia.

Answer 6

It is subdivided into the alar and prevertebral fascia. Both extend superiorly from the cranial base, but the alar fascia fuses with the middle cervical fascia and extends into the upper mediastinum, and the prevertebral fascia extends to
the level of the coccyx. The alar fascia and prevertebral
fascia fuse at the vertebral transverse processes and after
joining, envelop the paraspinous muscles.

Question 7

Describe the anatomy of the suprasternal space

space of Burns

Answer 7

The inferior insertion of the superficial (investing) fascia
splits just above the manubrium attaching anterior to the
manubrium and posteriorly to the interclavicular ligament.
This small potential space contains a portion of the anterior jugular veins, and the sternal heads of the sternocleido-
mastoid muscle.

Question 8

Define the boundaries of the buccal space.

Answer 8

The buccal space is created by the buccinator muscle
medially; the superficial layer of the deep cervical fascia and
the muscles of facial expression laterally and anteriorly; and
the muscles of mastication, mandible, and parotid gland
posteriorly. It primarily contains adipose tissue (buccal fat
pad), minor salivary glands, accessory parotid tissue, and
facial/buccal arteries, veins, and lymphatics. The buccal fat
pad is pierced by the parotid duct as it courses to the
buccinator and eventually enters the mouth opposite the
second upper molar.

Question 9

Define the mechanism of spread of infection (or

tumor) to and from the buccal space.

Answer 9

It permits spread between the mouth, parotid space, and masticator space from deficient fascial compartmentalization along the superior, inferior, and posterior limits.

Question 10

Define the boundaries of the carotid space.

Answer 10

The carotid sheath contains the carotid artery, internal
jugular vein, vagus nerve, and jugular lymphatic chain. All
three divisions of the deep cervical fascia form the carotid
sheath. It extends from the skull base to the mediastinum;
anteriorly lies the sternocleidomastoid muscle, posteriorly

the prevertebral space, and medially the visceral compart-
ment.

Question 11

Review the risk factors for carotid blowout.

Answer 11

Radiation, salivary fistula, malnutrition, hypothyroidism, T-
incision over the great vessels, radical neck dissection

Question 12

Define the boundaries of the danger space.

Answer 12

The danger space is a potential space that rests between the
alar fascia and the prevertebral fascia. Infections in this area
can communicate with the thorax (mediastinum) to the
level of the diaphragm.

Question 13

Define the boundaries of the masticator space.

Answer 13

The masticator space is created from the superficial layer of
the deep cervical fascia surrounding the masseter laterally
and the pterygoid muscles medially. It contains masseter muscle, pterygoid muscles, inferior tendon of the tempo-
ralis muscle, ramus, and posterior body of the mandible, internal maxillary artery, and the inferior alveolar neuro-
vascular bundle.

Question 14

Define the boundaries of the parapharyngeal

space.

Answer 14

It is shaped as an inverted pyramid with the base at the
cranial base and the apex at the hyoid bone. Anteriorly, it is
bound by the pterygomandibular raphe, posteriorly be the
prevertebral fascia, medially by the superior pharyngeal
constrictor, and laterally by the parotid, mandible, and
lateral pterygoid.

Question 15

How is the parapharyngeal space commonly

divided?

Answer 15

Prestyloid and poststyloid compartments are divided by the
tensor-vascular-styloid fascia connecting the tensor veli
palatini and the styloid process.

Question 16

What structures are contained within the presty-

loid space?

Answer 16

Fat, lymph nodes, minor salivary gland tissue, internal
maxillary artery, and the inferior alveolar, auriculotemporal
and lingual nerves

Question 17

What structures are contained within the post-

styloid space?

Answer 17

Carotid artery, internal jugular vein, cranial nerves 9

through 12, and the superior sympathetic chain

Question 18

What is the syndrome that follows the para-

pharyngeal space or parotid surgery that causes pain with the onset of eating?

Answer 18

First-bite syndrome

Question 19

Define the boundaries of the parotid space.

Answer 19

It is created by the superficial layer of deep cervical fascia as it surrounds the mandible and parotid gland and contains the parotid gland and parotid lymph nodes, the facial nerve, posterior facial vein, and facial artery.

Question 20

Describe the mechanism of infection or tumor spread from the parotid space to the paraphar-
yngeal space.

Answer 20

The superomedial parotid space fascia is deficient, allowing
for direct spread into the parapharyngeal space via the
stylomandibular tunnel.

Question 21

Define the boundaries of the peritonsillar space.

Answer 21

It is bound by the palatine tonsil medially and the superior
pharyngeal constrictor, palatoglossus, and palatopharyngeus
medially, superiorly, inferiorly, anteriorly, and posteriorly. It
contains loose areolar tissue and minor salivary glands.

Question 22

Define the boundaries of the prevertebral space.

Answer 22

It extends from the skull base to the coccyx and is bordered
anteriorly by the prevertebral fascia, posteriorly by vertebral
bodies, and laterally by the transverse processes of
vertebrae.

Question 23

Describe the sequential layers and spaces (super-

ficial to deep) of the posterior pharyngeal wall.

Answer 23

Mucosa, pharyngeal constrictor, buccopharyngeal fascia, retropharyngeal space, alar fascia, danger space, prevertebral fascia, prevertebral space

Question 24

Define the boundaries of the sublingual space.

Answer 24

It contains the sublingual gland, Wharton duct, and lingual
and hypoglossal nerves and is bound superiorly by the
mucosa of the floor of mouth, laterally by the mandible,
inferiorly by the mylohyoid, medially by the genioglossus,
and anteriorly by the mandible.

Question 25

What are the two divisions of the submandibular

space?

Answer 25

It is subdivided into the sublingual and submaxillary spaces,
which are separated by the mylohyoid. These two spaces
communicate at approximately the second molar.

Question 26

Define the boundaries of the submaxillary (sub-mylohyoid) space.

Answer 26

It contains the submandibular gland and is bound superiorly
and medially by the mylohyoid muscle, inferiorly and
posteriorly by the digastric muscle, and laterally and
anteriorly by the superficial layer of the deep cervical fascia
and mandible.

Question 27

Define the boundaries of the infratemporal fossa.

Answer 27

● Located inferior and medial to the zygomatic arch
● Anterior: Posterolateral portion of maxillary sinus
● Lateral: Ramus of the mandible
● Medial: Lateral pterygoid plate
● Superior: Greater wing of the sphenoid bone
● Inferior: Medial pterygoid muscle
● Posterior: Articular tubercle of the temporal bone,
glenoid fossa

Question 28

Describe the branches of the three segments of

the internal maxillary artery.

Answer 28

● First (lateral) portion: Deep auricular artery, anterior
tympanic artery, middle meningeal artery, inferior
alveolar artery, accessory meningeal artery
● Second (middle) portion: Masseteric artery, pterygoid
branches, anterior and posterior deep temporal arteries,
buccal artery
● Third (medial) portion: Sphenopalatine artery (terminal
branch), descending palatine artery, infraorbital artery,
artery of the vidian canal, anterior, middle, and posterior
superior alveolar artery

Question 29

Define the boundaries of the pterygopalatine

fossa.

Answer 29

● Located medial to the infratemporal fossa
● Anterior: Posteromedial portion of maxillary sinus
● Lateral: Pterygomaxillary fissure and infratemporal fossa
● Medial: Perpendicular plate of the palatine bone
● Superior: Body of the sphenoid bone
● Inferior: Pterygopalatine canal
● Posterior: Root of the pterygoid plates

Question 30

Name the foramina communicating with the

pterygopalatine fossa.

Answer 30

● Anterior: Inferior orbital fissure
● Lateral: Pterygomaxillary fissure
● Medial: Sphenopalatine foramen
● Interior: Greater palatine canal
● Posterior: Vidian canal, foramen rotundum

Question 31

What important structure may be encountered if

the vidian canal is followed posteriorly?

Answer 31

The second genu of the internal carotid artery

Question 32

Define the boundaries of the temporal fossa.

Answer 32

It is located between the superficial layer of the temporalis
fascia and the periosteum of the squamosal portion of the
temporal bone and is subdivided into the superficial and
deep layer by the temporalis muscle. It contains the internal
maxillary artery and inferior alveolar nerve.

Question 33

During submandibular gland excision, the marginal mandibular nerve cannot be readily identified. What strategy can be used to decrease the risk of marginal mandibular nerve injury?

Answer 33

The common facial vein can be identified low, ligated, and
divided and then reflected superiorly because the marginal
mandibular nerve rests superficial to the common facial
vein and facial artery in the region of the mandibular notch.

Question 34

Describe the location and course of the hypoglossal and lingual nerves in the region of the submandibular gland.

Answer 34

It is located deep to the digastric muscle and mylohyoid and
superficial to the hypoglossus muscle. The lingual nerve is
located cephalad to the hypoglossal nerve.

Question 35

What landmarks can be used for identification of

the accessory nerve during level 2 neck dissection?

Answer 35

Transverse process of C1, anterolateral to the internal
jugular vein, two fingerbreadths below the mastoid tip, or
just as it runs posterior to the sternocleidomastoid 1 to
2 cm above the Erb point

Question 36

Describe the location of the phrenic nerve and superior sympathetic chain.

Answer 36

It is located anterior to the anterior scalene muscle. The

phrenic nerve runs lateral to the sympathetic chain.

Question 37

The hypoglossal nerve is “pinned” by what artery as

it descends behind the digastric muscle?

Answer 37

The occipital artery

Question 38

Describe five methods or landmarks for identifying

the facial nerve during parotidectomy.

Answer 38

The tragal pointer, tympanomastoid suture line, level of the digastric groove (posterior digastric muscle), retrograde
from marginal mandibular nerve at mandibular notch,
anterograde from the vertical segment of the mastoid

Question 39

During deep-lobe parotidectomy, what arteries

must be divided for en bloc removal?

Answer 39

External carotid artery, superficial temporal artery, internal
maxillary artery

Question 40

Which cervical rootlets contribute to the ansa

cervicalis?

Answer 40

C1, C2, and C3

Question 41

Which deep neck spaces involve the entire length

of the neck?

Answer 41

Four: the retropharyngeal, danger, prevertebral, and carotid

spaces

Question 42

Describe the parasympathetic innervation to the

parotid gland.

Answer 42

Inferior salivatory nucleus → cranial nerve IX (Jacobson
nerve) → lesser superficial petrosal nerve → otic ganglion →
auriculotemporal nerve (V3) → parotid gland

Question 43

Describe the parasympathetic innervation to the

submandibular gland and sublingual glands.

Answer 43

Superior salivatory nucleus → nervus intermedius → cranial nerve VII → chorda tympani → lingual nerve → submandibular ganglion → submandibular gland

Question 44

Describe the parasympathetic innervation to the

lacrimal gland.

Answer 44

Superior salivatory nucleus → greater superficial petrosal
nerve → vidian nerve → sphenopalatine ganglion → lacrimal
branch V1 → lacrimal gland