Face and Scalp Flashcards
Bones forming the Facial skeleton
- (Frontal)
- (Ethmoid)
- Nasal
- Zygomatic
- Maxilla
Only movable facial bone
Mandible
Trigeminal Nerve - CN V
3 branches:-
- Ophthalmic
- Maxillary
- Mandibular
Ophthalmic
Vi or V1
Sensory
Passes through the Superior Orbital Fissure
Maxillary
Vii or V2
Sensory
Passes through the Foramen Rotundum
Mandibular
Viii or V3
Mixed
Passes through Foramen Ovale
Cutaneous innervation of the face
Sensory nerves of face enter though a series of foramina: V1 - Supraorbital; Supratrochlear
V2 - Infraorbital
V3 - Mental; Auriculotemporal
Ophthalmic V1 sensory to:
- Skin of forehead (most of)
- Conjunctiva
- Upper eyelid, bridge of nose
- Frontal sinus
- Antero-superior nasla cavity (muscosa)
Maxillary V2 sensory to:
Most of skin of cheek, upper lip and all structures deep to them
- upper teeth
- gums
- oral aspect of hard and soft palate
- maxillary sinus
- posterior-inferior nasal cavity
Mandibular V3 sensory to:
- Skin of temple
- Most of skin over lower jaw
Mandibular V3 Motor to:
- Muscles of Mastication
- Tensor tympani (dampens down sound i.e. from talking and chewing)
- Tensor palatini (moves hard palate)
- Anterior belly of digastric
Inferior alveolar branch of Mandibular branch of CN V
- enters the mandibular bone through the mandibular foramen
- Used to deliver a Mandibular block
- Branches off to the teeth as the Inferior Dental Plexus
Surgical management of Trigeminal neuralgia
posterior fossa craniotomy (removing a bone flap from the skull) at the confluence of the sigmoid and transverse sinus
Vascual decompression of CN V
Facial artery
Branch of the External Carotid Artery
Just above the Linguinal artery, which after a tortuous journey, ends as the Angular Artery at the medial commisure of the eye
Transverse Facial Artery
Runs just above the Parotid Duct Branch of the Superficial Temporal Artery
Common carotid artery - splits into 2
- ICA : supplies Brain and the Circle of Willis
- ECA: supplies the face (external)
Facial Vein (anterior facial vein)
Commences at side of root of the nose as a direct continuation of the angular vein
Lies BEHIND the Facial Artery and follows a less tortuous course
Receives blood from the External Palatine vein before:
- joining the ant branch of the Retromandibular vein to form the Common Facial Vein
- Draining directly into the Internal Jugular Vein
Clinical importance of Facial Vein
has a direct connection to the Ophthalmic vein and then to a deep venous sinus within the cranial activity, Cavernous Sinus.
Bacteria can enter the facial vein and gain access to internal cranial structures resulting in infection there
Muscles of Facial Expression
- Epicranius : Frontalis & Occipitalis
- Orbicularis Oculi
- Orbicularis Oris
- Buccinator
- Zygomaticus
- Platysma
Epicranius: Frontalis & Occipitalis
- Origin to Insertion
- Action
Origin/Insertion:
- Cranial aponeurosis
- Eyebrows
Action:
- Raises the eyebrows
Orbicularis Oculi (eye)
- Origin to Insertion
- Action
Origin to Insertion:
- Portions of the frontal and maxilla
- to skin around the eyes
Action:
- Blinks
- Closes eyes
Orbicularis Oris (mouth)
- Origin to Insertion
- Action
Origin to Insertion:
- Skin around mouth
Action:
- Closes and protrudes the lips
Buccinator:
- Origin to Insertion
- Action
Origin to Insertion:
- -Mandible/Maxilla to skin around mouth
Action:
- Flattens cheek against teeth
- Keeps food in mouth whilst you chew
Zygomaticus:
- Origin to Insertion
- Action
Origin to Insertion:
- Zygomatic bone to corner of lips
Action:
- Raises corner of mouth
Platysma
- Origin to Insertion
- Action
Origin to Insertion:
- Fascia of chest
- To lower border of Mandible
Action:
- Draws mouth downward
Facial Nerve
CN VII
Mneumonic: Two Zulus Borrowed My Cat
Motor Branches:
- Temporal
- Zygomatic
- Buccal
- Marginal Mandibular
- Cervical
Facial Nerve
Branchial Motor (special visceral efferent)
Supplies:
- THE MUSCLES OF FACIAL EXPRESSION
- Posterior belly of Digastric muscle
- Stylohyoid
- Stapedius
Facial Nerve
Visceral Motor (general visceral efferent)
Parasymp innerv of:
- lacrimal
- submandibular
- sublingual glands
- mucous membranes of the nasopharynx, hard and soft palate
Facial Nerve
Special sensory (Special afferent)
TASTE SENSTATION FROM THE ANT 2/3RDS of tongue hard and soft palates
Facial Nerve
General Sensory (General somatic afferent)
General sensation from the skin of the concha of the auricle and from a small area behind the ear
Bell’s Palsy
- Paralysis of muscles on one side of face
- Due to swelling of facial nerve (CN VII)
- Usually develops over 1-3 days
- Slowly improves/completely goes away in 1-3 months
- Most ppl with Bell’s Palsy completely recover; some are left with weakness on side of face
- *Most common in adults in the 40s
Parotid Gland
- Tightly enclosed in fascia; swelling is painful = “mumps”
- Contains TERMINAL branches of CN VII
- Parotid duct lies on the Masseter and pierces the Buccinator
- Duct opens into the oral cavity near the second upper molar tooth
- External Carotid divides into its terminal branches in the gland (maxillary art. and superficial temporal)
SCALP
N.B. also a useful acronym
Scalp is made up of 5 layers:
- Skin
- Connective tissue
- Aponeurosis - occipito-frontalis
- Loose connective tissue
- Periosteum
Arterial supply of Scalp
- Superficial Temporal Artery
- Supraorbital Artery
- Occipital and Posterior Auricular Arteries
These are free anastomoses from side to side.
Vessels run through the dense connective tissue (in the 2nd layer of the scalp)
Scalp
Cutaneous Innervation
- Front - Supraorbital nerve Vi Ophthalmic
- Side - Auriculotemporal nerve Viii Mandibular
- Back - Greater Occipital nerve CN II (optic)
- Side - Lesser Occipital nerve CN II (optic)
Panda’s Eyes
Loose connective layer of scalp:
- can allow bacteria/fluid to pass freely from the post. aspect of the scalp into the eyelids in front
- Trauma in back of head: can result in blood showing up in the eyelids
- should make you suspect something going on in the back of the head
What is the skin over the angle of the jaw supplied by?
CN II Optic nerve
