Orbit And Nasal Cavity Flashcards
7 bones of orbit
Frontal I sphenoid, ethmoid,
7 orbital openings
Supraorbital foramen/notch
Optic canal
Superior orbital fissure
Ethmoidal foramina
Nasolacrimal canal
Inferior orbital fissure
Infraorbital foreman
Lacrimal gland
Function: tear production to moisturize eye and emotional expression
Location: supralateral to orbit
Lacrimal gland drainage
Lacrimal gland innervation
Sympathetic: postganglionic axons from the superior cervical ganglion
Parasympathetic: preganglionic axons from CN 7 form the greater petrol nerve
Innovation
3 layers of eye
Out layer
Choroid: blood vessel plexus
Retina
Eye: anterior chamber
Iris: pupil, * pupillary light reflex: regulating light passing in
Ciliary body
Aqueous
Eye posterior chamber
Functions in eye
Light detection and transformation
Light pathway : cross
Light processing
Converging, reverse the light transmission pathway
Involves: bipolar neurons, ganglion cells
Sensation vs.
Orbit: neuromuscular supply
Somatosensory innovation: ophthalmic nerve (CN 5 division 1)
Nasociliary nerve
Frontal nerve
Lacrimal nerve
** NFL → medial to lateral
Orbit: blood supply
*Ophthalmic artery
Central retrial artery
Ciliary artery
Supra trochear and supra-orbital artery
Ethmoid artery mu dorsal nasal artery branches
Lacrimal artery
** Clinical: anastomosis of the internal and external carotid
Eye muscle innovations
Sympathetic: postgauglianic fibers from the superior cervical ganglion deep petrosal nerve
Parasympathetic: preganglionic fibers from the CN 3 to form the ciliary ganglion
Ciliary body
Iris innovation
Sympathetic
Parasympathetic
Horner’s syndrome
Sympathetic nonfunctional, parasympathetic not balanced
Symptoms: constricts pupils, eyelid ptosis, No sweating on the affected side
Sympathetic component in the cutaneous innovation
Pupillary reflex
Iris adjustment
Afferent: CN 2
Efferent: CN 3
** blind people can have normal popular reflex: ganglion cells still do light detection
Eyelid: structures
Muscle tendons
Orbital septum
Palpebral ligament: lateral/medial
Tarsus plate: sup/inf
Eyelid: neurovascular supply
V(1) and v(2) terminal branches
Anastomosis of external and internal carotid artery terminal branches
Eyelid : functions
Protection: recall blink reflex
Facial expression: wink
Orbicularis oculi
2 parts: close
1. Orbital part - wink
2. Palpebral part: blink
CN 7
Levator palpebrae superioris
Superior tarsal muscle
Smooth muscle, open
P: musculotendinous junction
Superior Rectus
Superior oblique
Inferior Rectus
Lateral Rectus
Medial Rectus
Inferior oblique
Extraocular muscle innervation
CN III
Eyeball convergence
Add of both eyeballs at the same time
Pathological: strabismus- eyes are not lined up properly
Esotropia
Adducted eyeballs: CN 6 palsy
Exotropia
Hypertropia
Hypotropia
Depressed eyeballs: inferior oblique - CN 3 palsy
Nasal cavity boundary
Lateral wall: irregular hyaline cartilage, nasal conchae
Medial wall:
Roof
Floor
Anterior
Posterior
Nasal bones: lateral wall
Nasal bone, maxilla, superior/middle ethmoid bone/ inferior nasal conchae
Nasal bones: roof
Frontal, ethmoid, sphenoid
Nasal bones: floor
Nasal bones: septum
Nasal cartilage
Hyaline cartilage, lateral wall and septum
Nasal cavity divisions
Vestibule: hair
Respiratory region: conducting air to the respiratory tract
Olfactory region: smell
Meatus
Passageways form btw nasal conchae and nasal cavity floor and roof
Increases surface for air contact
Cranial sinuses
Frontal, maxillary, ethmoid, sphenoidal mastoid
Cranial sinuses function
Produces mucus to moisture for nasal cavity
Lightens skull
Drainage of sinuses into nasal cavity
Inferior meats: nasolacrimal duct
Middle meatus:
How much mucus is produced daily
1-2 liters
Mucosal glands
Humidify air
Absorbs particles
Dissolves molecules
Balance air temperature to body temp
** around choanae, air ~30°C and 97% humidity
Mucosal glands: neuromuscular
CN 7
parasympathetic, pterygopalatine ganglion
Sympathetic: can be inhibited
Smell and chemical sensation
CN 1: thinnest nerve and nonmyclinated
Nasal cavity arteries and veins
Terminal branches from internal and external carotid arteries