Temporal And Parotid Regions: Mon., Oct 2

Front 1

Temporal region:

Back 1

*made from portions of frontal, parietal, squamous temporal, and greater wing of sphenoid
**all converge on pterion-thin area of bone
***deep to pterion is middle meningeal artery (CC: impingement results in epidural bleed)

Front 2

CC: Uncal Herniation

Back 2

*results from increased pressure on internal cranial contents
**tentorial notch-separates posterior and middle cranial fossae; uncas or most medial portion of temporal lobes forced down through notch and brain stem is compromised (both arterial and epidural bleeds)

Front 3

Parts of mandible:

Back 3

1. head
2. neck
3. angle
4. ramus
5. coronoid process

Front 4

other associated features:

Back 4

1. zygomatic arch-inferior border of temporal fossa; has a zygomatic process from temporal bone and temporal process from zygomatic bone
2. medially, styloid process, which is associated with 3. stylomastoid foramen, where facial nerve leaves skull
4. external acoustic meatus
5. mandibular fossa has articulation with head of mandible to zygomatic arch

Front 5

Vasculature:

Back 5

1. ECA: terminates by dividing into superficial temporal artery and maxillary artery medial to mandible
2. Inferiorly, EJV being formed by retromandibular and posterior auricular veins

Front 6

Muscles of temporal region:

Back 6

1. temporalis: originates from temporal fossa and temporal fascia; inserts on coronoid process of mandible and anterior aspect of ramus; main actions: elevation and retracts mandible after being protruded
2. masseter: originates on inferior and medial surface of zygomatic arch; inserts on lateral surface of ramus and coronoid process; actions: elevates and retracts

Front 7

Auriculotemporal nerve (ACT):

Back 7

*branch of CNV
* exits infratemporal fossa onto fossa just anterior EAM and through joint formed by head of mandible and temporal bone (superiorly)
*provides postganglionic parasympathetics to parotid gland for secretomotor function
* comes from otic ganglion which receives preganglionic parasympathetics from glossopharyngeal (CNIX)
***ACT nerve gives innervation to parotid gland but also to sensory anterior part of external ear and temporal fossa

Front 8

Sensory innervation:

Back 8

1. V3-lateral face and anterior ear
2. ACT-anterior part of external ear
**external ear has wide sensory distribution: CNV,VII,IX,X

Front 9

Parotid Gland:

Back 9

*sits in bed
*stroma-connective tissue of gland
*gland and stroma part of deep investing fascia of neck
*borders: a) anterior-masseter muscle, mandible, posterior border of medial pterygoid; b) posterior-SCM, posterior belly of digastric, mastoid process; c)medial-styloid process and muscles (stylohyoid, styloglossus, stylopharyngeous

Front 10

Structures pass through stroma of parotid:

Back 10

1. facial nerve
2. retromandibular vein
3. ECA