Scalp and Superficial Face Flashcards
5 layers of the scalp
Skin
Connective tissue (dense) - neurovascular
Aponeurosis - connects facial muscles to skin
Loose connective tissue - susceptible to infection that can spread through the facial muscles
Pericranium - periosteum of the cranium, neurovascula
Scalp proper includes
Skin, dense connective tissue and aponeurosis
Emissary vein and infection
Infection in the loose connective layer can erode into emissary vein, spread to the dural sinuses and result in meningitis
Scalp injuries/detached scalp
Neurovascular supply goes from inferior to superior from the dense connective tissue layer. Can be reattached since there is still neurovasculature coming from below supplying the scalp (flow is still there despite the ends being cut)
-U shaped scalp flap during surgery helps preserve the neurovasculature
Gaping wounds on scalp
Usually due to cutting the aponeurosis layer (connected to the muscles, so gaping occurs), especially in the coronal plane. If the wound does not gape, it only cut through the first 2 layers
Course of the parotid gland and parotid duct
- Goes from the superior zygomatic arch to the inferior border of the mandible, may extend into the submandibular triangle
- Duct dives into the buccinator muscle
Clinical significance of the parotid gland
Neurovasculature passes through the parotid gland. Facial N. branches, retromandibular v. and the external carotid a.
Tumors compressing the parotid gland can also affect these vessels
-Also mumps clinical correlation from the triangles lecture
What foramen does Facial N. (CN VII) exit to get into the face?
Stylomastoid foramen, between the styloid process and mastoid process
Course of the facial N.
Exits the stylomastoid foramen into the face > Dives into the parotid gland and branches into 5 branches
What are the five branches of the facial N.?
Tiny Zebra Bit My Cheek
Temporal N. Zygomatic N. Buccal N. Mandibular N. Cervical N.
Clinical significance of facial N. branching (in relation to muscle innervation)
No specific innervations to specific muscles. There are communicating branches between each of the nerve branches. Nerves innervate different muscles in different individuals
Which cranial nerve carry parasympathetic fibers (preganglionic)?
CN III, VII, IX, X
Which cranial nerve carries majority of the postganglionic parasympathetics?
CN V
Tears are produced via
Lacrimal gland, via the Greater Petrosal N.
Innervation of the Facial N.
Sensory: taste to the anterior 2/3 of the tongue via the chorda tympani, upper EAM
Motor: Muscles of facial expression, stapedius, P. belly of the digastric
Parasympathetic: Lacrimal gland, submandibular and sublingual salivary glands (also via chroda tympani)
Bell’s palsy:
Facial N. lesion causing ipsilateral paralysis of the muscles of facial expression
Cannot close eyes (drying out the cornea), cannot close mouth etc.
Draw the pathway of the Facial N.
Refer to drawings
Draw the cutaneous innervations of the scalp and face
Refer to drawings
Draw the course of the Trigeminal N.
Refer to drawings
Cutaneous facial innervations:
A. Ophthalmic N. (via Supraorbital and Supratrochlear branches) (via External nasal n.) B. Infraorbital N. (via Nasal and Palprebal branches) C. Mandibular N. (via Auriculotemporal) (via Buccal branch) (via Mental N.)
A.
1) skin of eyelids, forehead
2. ) skin of nose
B
1.) skin of nose and lower eyelids respectively
C.
- ) skin of external ear
- ) skin of cheek
- ) skin of mental region
Which type of muscles does trigeminal nerve innervate?
Muscles of mastication via the mandibular nerve branch
Herpes zoster (shingles):
Chicken pox and shingles virus can linger latent in the sensory ganglion. Reactivation of the virus in older age follows the nerve distribution of the ganglion. So if it lies dormant in the trigeminal ganglion, the shingles will occur in the areas cutaneously innvervated by the trigeminal nerve
So in this patient it appears in areas innervated by the V1 branch
Draw the superficial arteries of the face
Refer to drawings
Superficial temporal a. runs with what nerve?
Auriculotemporal n.
Which facial arteries form anastomosis?
Right and left labial arteries
Angular and Supratrochlear arteries
Supraorbital and superficial temporal arteries
So branches from ECA and ICA anastomose with each other
Which facial arteries originate from the internal carotid a?
Supraorbital a. and Supratrochlear a.
Draw the veins of the superficial face
Refer to drawings
Facial infections and veins/venous sinuses
Superior and Inferior ophthalmic veins + Angular veins + Deep facial veins (via the pterygoid venous plexus) all connect with the cavernous sinus. Infections in the face can drain back to the cavernous sinus due to these connections and cause meningitis and other issues
What nodes make up the Superficial ring/Pericervical collar?
Submental Submandibular Parotid/preauricular Mastoid Occipital
What do these superficial ring nodes drain? Occipital Mastoid Parotid Submandibular Submental
-Posterior scalp and neck
Posterior lateral half of the scalp
-anterior ear and upper half of face and scalp
-where the facial artery goes
-bottom part of the chin, lower lip, tip of tongue
Submental, Submandibular and Parotid nodes drain to which nodes?
How about Occipital and mastoid?
Deep cervical nodes
Superficial cervical nodes, but eventually will drain to the deep cervical nodes
Superficial cervical nodes travel with which vessel?
Deep cervical nodes travel with which vessel?
- External jugular v.
- Internal jugular v.
What nodes make up the deep cervical nodes?
Jugulo-digastric
Jugulo omohyoid
