What are the contents of the posterior triangle?
- 2 subtriangles: occipital and supraclavicular
- -CN XI
- -Roots and trunk of brachial plexus (bw anterior and middle scalene)
- -Long thoracic
- -dorsal scapular
- Arteries: Subclavian and Suprascapular
- Veins: Subclavian and External Jugular
- Lymph Nodes: Deep and Superficial LN; Supraclavicular LN
Four parts of the deep fascia of the neck
- 1) Investing layer
- 2) pretracheal layer
- 3) Paravertebral layer
- 4) carotid sheath
What are the contents of the pretracheal layer?
- thyroid and parathyroid glands
What are the contents of the carotid sheath?
- common and internal carotid
- deep cervical LNs
- phrenic nerve
Three subtriangles of the anterior triangle and the muscle that subdivides them
- 1) Carotid triangle: superior belly of omohyoid
- 2) Muscular triangle: omohyoid->digastric
- 3) Digastric triangle: Digastric to midlin of neck
What are the contents of the carotid sheath?
- 1) Vagus nerve (always posterior)
- 2) IJV (always lateral)
- 3) Common carotid
- 4) deep LNs
- 5) ansa cervicalis embedded in anterior sheath
What are some important structures that superficially cross the IJV from superior to inferior? Where does it terminate?
- 1) Spinal Acc. N
- 2) post. belly of digastric
- 3) omohyoid
- 4) AJV
terminates behind the sternoclavicular heads of SCM
List the anterolateral, medial, and posterior relations of the thyroid gland.
- AL: skin and superficial fascia; sup. belly of omohyoid (upper end of gland); anterior border of SCM (lower end); sternothyroid and sternohyoid muscles (middle portion)
- Medially: thyroid and cricoid cartilages (upper end); upper 6 rings of trachea and esophagus; recurrent laryngeal n (lower end)
- Posteriorly: common carotid; parathyroid glands; inferior thryoid artery
Trace the path of the parotid duct
superficial to the masseter (deep to transverse facial artery), dives medially into the buccal fat pat, pierces the buccinator, enters oral vestibule by 2nd maxillary molar.
What are the contents of the parotid sheath?
- parotid gland
- facial nerve
- retromandibular vein
- external carotid artery
- parotid LNs
What are the boundaries of the temporal region?
- superior and posterior: superior temporal line
- inferiorly: infratemporal crest
- anteriorly: frontal and zygomatic bones
- laterally: zygomatic arch
- floor: parts of pteroin bones (frontal, parietal, temporal, greater wing of sphenoid)
- roof: temporalis muscle
What are the contents of the temporal region?
- Temporalis muscle.
- Deep temporal nerve (off V3).
- Deep temporal artery (off maxillary artery).
- Auriculotemporal nerve (off V3).
- Superficial temporal artery (off ECA)
- Temporal nerve (off facial nerve).
Boundaries of the Infra-temporal region
- Superior: Greater wing of sphenoid
- medial: pterygoid plate
- lateral: ramus of mandible
- anterior: posterior maxilla
- posterior: styloid process
Contents of the infratemporal region
- Lateral and medial pterygoid muscles.
- Maxillary artery (with its branches).
- Pterygoid venous plexus.
- Mandibular nerve with its branches.
- Otic ganglion.
- Chorda tympani.
What is the rule of 2 for CN V3?
- 2 large elevators (temporalis, masseter)
- 2 pterygoid muscles (lateral, medial)
- 2 tensor muscles (tympani, palatine)
- 2 muscles of floor of mouth (digastric, mylohyoid)
Describe the three layers of the eye and their relation to one another
- 1) Outer fibrous tunic
- 2) Vascular (uveal) tunic (middle)
- 3) Retinal (nervous) tunic (innermost)
What is retinal detachment?
When the sensory layer pulls away from the pigment epithelium
Describe vision from the rods all the way to the optic nerve
1)impulses from photoreceptive rod or cone to bipolar cells
2) Bipolar cells contact ganglion cells (closest to the vitreous)
- 3) The ganglion cells (~ 1 million) send their axons (unmyelinated) to the optic
- nerve head (optic disc) where they come together as the optic nerve (now
- becomes myelinated)
- Horizontal cells
- and amacrine cells integrate the signals.
What are the 4 refractive media of the eye?
- 1) lens
- 2) aqueous humor
- 3) lens
- 4) viteous body
What is glaucoma?
Either too much or a blockage of the aqueous humor
What do tears consist of?
- other proteins
What are the derivatives of the first pharyngeal arch
Skeletal (neural crest): maxilla, mandible, zygoma, inner ear bones (incus and malleus), temp bone
muscle (paraxial): muscles of mastication, tensor tympani, ant belly of digastric, mylohyoid, tensor palatini
What are the derivatives of the second pharyngeal arch?
skeletal (neural crest): stapes, styloid process, upper half of hyoid
muscular (paraxial): muscles of facial expression, stapedius, stylohyoid, post belly of digastric
innervation: facial nerve
derivatives of the third pharygeal arch
skeletal (neural crest): lower half of hyoid
muscular (paraxial): stylopharyngeus muscle
innervation: glossopharyngeal (IX)
What are the derivatives of the 4th and 6th pharyngeal arches?
skeletal (neural crest): laryngeal cartilages
muscles (paraxial): pharyngeal constrictors, intrinsic laryngeal muscles, cricothyroid, levator palatini
What are the derivatives of the first pharyngeal pouch?
- middle ear cavity
- auditory (Eustachian) tube
What are the derivatives of the second pharyngeal pouch?
tonsillar fossa (palatine tonsils)
What are the derivatives of the third pharyngeal pouch?
- inferior parathyroid
What are the derivatives of the fourth pharyngeal pouch?
What are the derivatives of the four pharyngeal clefts (grooves). Name one clinical correlate
Cleft 1: external auditory meatus; external surface of tympanic membrane
Clefts 2-4: amalgamate and eventually regress
Clinical: If 2-4 fail to regress completely, you can have a painless brachial cleft cyst
Discuss tongue development, including innervation
1) Arch 1 forms anterior 2/3 (trigeminal), Arch 3 forms posterior 1/3 (glossopharyngeal)
2) All tongue muscles from occipital somites (Hypoglossal)
Describe the 5 portions of the lacrimal apparatus
- 1) Lacrimal gland: lies in fossa in superolateral orbit. innervated by parasymp fibres from CN VII
- 2) Lacrimal ducts: go from gland to superior conjunctival fornix (latin for arch)
- 3) lacrimal canaliculi drain to lacrimal sac
- 4) lacrimal sac drains to nasal cavity via nasolacrimal duct
- 5) nasolacrimal duct
What is the sensory innervation of the pharynx?
- Nasopharynx: trigeminal
- Oropharynx: glossopharyngeal
- laryngopharynx: vagus
List the anatomical relations of the pharynx (use the constrictors as a landmark)
above sup. constrictor: tensor veli palatini, levator veli palatini, auditory tube
b/n sup and mid const: stylopharyngeus muscle, stylohyoid membrane and ligament, Cn IX
b/n mid and inf const: internal branch of superior laryngeal nerve, superior laryngeal artery
Below inferior constrictor: recurrent laryngeal nerve, inferior laryngeal artery
What is Waldeyer's tonsillar ring
- group of lymphoid tissue containing:
- 1) Palatine tonsils. Lymphoid tissue lying between the palatoglossal and palatopharyngeal arches.
- 2) Pharyngeal tonsils. Lymphoid tissue lying in the roof of the pharynx.
- 3) Lingual tonsils. Lymphoid tissue lying at the base of the tongue.
- 4) Tubal tonsils. Lymphoid tissue surrounding the opening of the auditory tube.
What does the lower surface of the tongue contain?
- 1) frenulum lingulae (tongue tied) at midline
- 2) deep lingual VAN on either side of midline (why you dissolve pills under the tongue)
- 3) fibriated fold (ridge of mucous membrane)
Describe the cartilages of the larynx
- 1) epiglottis: one end attached to thyroid cartilage, glosso- and pharyngo- epiglottic folds move it
- 2) thyroid cartilage: biggest, attached to cricoid and hyoid by membranes
- 3) cricoid cartilage (C6): ring shaped, attached to thyroid cart and trachea
- 4) arytenoid: pair of cartilages with vocal processes
What are 4 imaging modalities and when are each best used?
- 1) plain film: face fracture, orbital injury, C spine injury
- 2) CT - acute head trauma, suspected acute intracranial hemorrhage, suspected mass or tumor, headache, mental status change
- 3) CT Agiography: stroke, aneurysms, vasculitis, congenital malformations
- 4) MRI: charact. of abnormalities seen in CT, seizure, tumor, strokes, infections, MS, post-surgical evaluation
What are the canadian C-spine rules?
List the bones and cartilage of the external nose
Bones: nasal bone, frontal process of maxilla
Cartilage: Alar (tip), lateral nasal, sides (almost near midline), septal
What are the boundaries of the nasal cavity?
- Roof: Nasal, frontal, ethmoid, spenoid bones
- floor: upper surface of hard palate
- medial wall: nasal septum
- lateral wall: three nasal conchae
What are the muscles that act on the palate and their innervation
- levator veli palatini - pharyngeal plexus
- tensor veli palatini - V3
- palatoglossus - pharyneal plexus
- palatopharyngeus - pharyngeal plexus
- muscular uvula - pharyngeal plexus
List the openings of the pterygopalatine fossa
- anteriorly: to orbit via inferior orbital fissure
- laterally: to the infratemporal fossa
- to the nasal cavity
- to the middle cranial fossa: through the foramen rotundum (V2)
- to the oral cavity:
- to the nasopharynx
What are the contents of the pterygopalatine fossa?
- maxillary nerve
- third part of maxillary artery
- pterygopalatine ganglion
Contents of the middle ear
- Auditory ossicles
- stapedius and tensor tympani muscles
- chorda tympani nerve
- tympanic plexus (nerves)
Describe the walls of the tympanic cavity
- 1) roof (tegmental): separated cavity from middle cranial fossa
- 2) floor (jugular): separates tympanic cavity from IJV
- 3) Medial or Labarynthine wall: separates from inner ear, oval window (stapes), round window, prominence where cochlea and run
- 4) Anterior (carotid) wall: separates from carotid canal. Has canals for tensor tympani and auditory tube
- 5) posterior or mastoid wall: stapedius attachment, prominance of facial nerve (chorda tympani)
- 6) lateral wall: tympanic membrane
What muscles actively open the auditory tube?
levator and tensor veli palatini
Describe the three layers of the tympanic membrane
- 1) outer (cuticular layer): keratinized, squamous epithelium
- 2) Middle (fibrous) layer: radial and circular sets of collagen fibres radiating from the handle of the malleus
- 3) inner (mucous) layer: special, resp, epithelium of the middle ear. No cilia or goblet cells
Describe the divisions of the membranous labyrinth of the inner ear.
What are the 6 sensory locations in the membranous labyrinth
- 3 crista ampullaris in the semicircular canals (head position, rotation)
- Organ of corti (hearing)
- Utricle and saccule (gravity and linear acc)
What supplies parasympathetic innervation to the parotid gland?