Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
94 Cards in this Set
- Front
- Back
Epibulbar (mucosal) epithelium
|
+goblet cells, NO rete ridges, keratin nor granular layer
|
|
epidermis
|
+rete ridges, keratin, granular layer, NO goblet cells
|
|
conjunctival epithelium
|
mucin secreting goblet cells
|
|
corneal epithelium
|
NO mucin secretors
|
|
Skin layers:
Basal cell |
cuboid or columnar w/ large nuclei aligned in single row above BM
|
|
skin layers:
Prickle cell |
polygonal w/ numerous hairlike filamentous connections btwn cells
|
|
skin layers:
Granular |
flat, long squamous cells w/ multiple keratohyaline granules
|
|
skin layers:
Keratin |
multiple eosinophilic layers of protein w/ no cellular details visible
|
|
Tears
Mucus |
innermost layer; secreted by conj; permits smooth/even distribution over corneal epi
|
|
Tears
Aqeous |
middle layer; secreted by glands or Crause & Wolfring; permits diffusion of O2 & metabolites to the cornea; >90% of tear volume
|
|
tears
lipid |
outermost layer; secreted by meibomian glands; retards tear evaporation
|
|
corneal thickness
|
superior>nasal>inferior>temporal
|
|
Schwalbes line
|
junction between K endo & nonpigmented TM endo
|
|
Muller cells
|
nuclei in INL; modified glial cells; basal process extend to form ILM; outer cell processes extend beyond ONL & are connected to photoreceptors by terminal bars (AKA ELM)
|
|
NFL
|
clinical significance=JXR, reticular retinoschisis
|
|
inner plexiform layer
|
axons of bipolar & amacrine cells & synapses of ganglion cells
|
|
inner nuclear layer
|
retinal BVs supply inner 1/3 (& all layers superficial to this)
|
|
outer plexiform layer
|
connections btwn photoreceptors, horizontal cells, bipolar cells
In macula=Henle’s layer; Clinical significance=CME; senile retinoschisis |
|
outer nuclear layer
|
Photoreceptors nuclei
|
|
ILM
|
footplates of muller cells; discontinuous over lattice degen
|
|
RPE
|
interdigitates w/ apical processes or rod & cone segments; densely adherent to Bruchs; taller w/ more pigment in macula; comprise outer blood-retinal barrier
|
|
bruch's membrane
|
5 layers: RPE basement membrane (BM), Inner collagenous zone (ICZ), elastic layer, OCZ, choriocapillaris BM
|
|
choriocapillaris
|
circulation from posterior ciliary arteries (i.e. no communication w/ ophthalmic artery)
|
|
macula
|
rods: cones=12:1 (up to 20:1); rod density is greatest 20-40 deg eccentric to fovea; cone density is greatest at fovea; at fovea, rods=cones; cones=40-50% are outside of macula
|
|
blood retinal barrier
|
inner=BV endothelium; outer=RPE
|
|
aqueous
|
more acidic & hypertonic than plasma; 15 x more ascorbate, sig less protein (0.2% vs 7%)
|
|
Conventional aqueous outflow
|
TM, Schlemm’s, episcleral/conj veins (85-90%), IOP dependent
|
|
Non-Conventional aqueous outflow
|
uveoscleral (10-15%), independent of IOP
|
|
Optic canal
|
in lesser wing of sphenoid, 8-10mm long & 6.5mm wide @ optic foramen; sympathetics, ON, ophthalmic art, nasociliary n, CN3, CN6
|
|
Ethmoidal foramina
|
at jxn of ethmoid & frontal bones
|
|
Sup orb fissure
|
separated from optic canal by bony optic strut; CN4, lacrimal & fronal N, sup orbital vein
|
|
Inf orb fissure
|
CN V2 (maxillary N), sphenopalatine ganglion branches, zygomatic N, Inf orb V;
walls: medially=maxilla; anteriorly=zygomatic; laterally=Gr wing of sphenoid & palatine bone |
|
Orbit Floor
|
MaPZ (maxilla, palatine, zygomatic)
|
|
Orbit Medial wall
|
maxilla, lacrimal, ethmoid, medial part of frontal
|
|
Whitnall’s Lat orbital tubercle
|
entirely on zygomatic bone (2mm inf to frontozygomatic suture)
Lockwoods ligament Lateral rectus check ligament Lateral canthal tendon Lateral horn of levator aponeurosis |
|
Lockwoods ligament
|
globe hammock; part of lower lid retractor system (w/ intermuscular septae & tenons); posterior—arises from fibrous attachments on inf side of inf rectus; extends anteriorly as capsulopalpebral fascia (lower lid retractor); medial & lateral horns—attach to retinacula (media= posterior lacrimal crest; lateral= Whitnall’s tubercle)
|
|
Whitnall’s ligament
|
superior transverse ligament; sheath of ant levator muscle; 10mm superior to tubercle attaching to frontal bone & lacrimal gland capsule
laterally—arises from compact sheath of ant levator & attaches to capsule of lacrimal gland & lateral orbital wall above lat orb tubercle; medially—arrises from trochlea; +extensions to retinacula; limits eyelid elevation |
|
orbital septum
|
fibrous sheet arises from arcus marginalis (jxn of orbital periosteum & pericranium; fuses on ant surface of levator (upper) & retractor (lower) aponeurosis w/ pre-aponeurotic fat separating
|
|
Lacrimal Sac fossa
|
bound by lacrimal (post lacrimal crest) & maxillary bones (ant lacrimal crest); in DCR, ostomy is made in maxillolacrimal suture line; lined by pseudostratified columnar epi; ant to septum (not w/in orbit); orbicularis contracts (CN 7)-->preseptal portion puts traction on lacrimal diaphragm (fascia lateral to sac)-->lacrimal pump process
|
|
lacrimal Ducts
|
3-5mm into inferior meatus before opening at valve of hasner (mucosal fold)
|
|
lacrimal gland
|
in frontal bone in ant lat orbit; orb & palpebral lobes are separated by lateral horn of levator; orbital lobe empties into palpebral lobe which empties into conj fornix; blood supply from lacrimal artery (branch of ophthalmic artery)
|
|
Accessory lacrimal Krause & Wolfing (lid)
|
eccrine
aqueous |
|
Accessory lacrimal glands in plica & caruncle
|
eccrine
aqueous (Sebaceous) |
|
meibomiam gland
|
holocrine
oil |
|
glands of zeiss
|
follicles of cilia & caruncle
holocrine oil |
|
glands of moll
|
apocrine
mucus |
|
Goblet cell:
|
in conj, plica, caruncle
holocrine mucus |
|
typical sweat gland
|
eccrine
|
|
lacrimal gland
|
eccrine
aqueous |
|
vascular supply to cardinal muscles
|
Lacrimal artery—supplies lateral rectus (1 vessel); all others=ophthalmic artery
|
|
Annulus of Zinn
|
origin of all 4 recti; Sup oblique & levator are superior to annulus; inf oblique originates medially on the maxilla
|
|
Innervation of muscles
|
superior (oblique & recus) are innervated by contralateral nuclei
all others have ipsilateral innervation |
|
Smallest muscle belly
|
Superior oblique
|
|
Longest tendon
|
Superior oblique
|
|
shortest tendon
|
inferior oblique
|
|
Superior oblique
|
Anatomic origin at orbital apeax. Mechanical origin at trochlea. Max effect when adducted 51 deg
|
|
Inferior oblique
|
Anatomic & mechanical origin both from anteromedial orbital floor
|
|
Superior rectus
|
Recession=widening of palpebral fissure; resection=narrowing of fissure as SR is loosely attached to levator complex
|
|
Inferior rectus
|
Recession=widening of palpebral fissure; resection=narrowing of fissure as IR’s sheatrh gives rise to capsulopapebral fascia
|
|
Twitch movement
|
Glycolysis; en plaque innervations
|
|
Tonic movement
|
Aerobic metabolism; en grappe innervation
|
|
neuromuscular innervation
|
Muscle is innervated at posterior 1/3, anterior 2/3 junction
|
|
V1 (ophthalmic)
|
"NFL" (nasociliary, frontal, lacrimal);
Frontal-->supraorbital & supratrochlear N |
|
V2 (maxillary)
|
goes through foramen rotundum: infraorbital, zygomatic, sup alveolar N, pterygopalatine ganglion
Zygomatic-->zygomaticofacial & zygomaticotemporal |
|
Sup Orb Fissure
|
CN 3,4,V1 & 6
|
|
Inf Orb fissure
|
CN V2
|
|
Optic nerve
|
intracranial portion has little slack; (“125-1017”=1 intraocular, 25=intraorbital, 10=intracanalicular, 17=intracranial); enters skull inf to frontal lobe & ACA & medial to ICA & is then no longer sheathed
|
|
Optic chiasm
|
inf fibers cross first; post portion=macular fibers; ~1cm above pituitary
|
|
Lat geniculate body
|
ipsilateral=2,3,5; contralateral=1,4,6
|
|
Optic radiations
|
inf radiations pass close to internal capsule—infarct-->sup hemianopic contralateral VF defect & contralat hemiparesis
|
|
Fused central nucleus
|
levator palpebrae
|
|
Eyelid functions
|
closure = CN7; Opening=CN3 (levator) & sympathetics (Muellers)
|
|
Pupil constriction
|
parasymp run w/ CN3-->ciliary ganglion-->short ciliary N
|
|
Pupil sympathetic pathway
|
3 neuron chain:
1)hypothalamus-->along brainstem--> 2) Intermediolateral column of spinal cord (ciliospinal center of budge (C8-T2))-->exits brainstem @ T1 & joins cervical sympathetic chain--> 3)superior cervical ganglion -->travels along carotid plexus -->branches join ophthalmic division of V1-->through ciliary ganglion to nasociliary & short ciliary nerve |
|
Vertical gaze
|
1) frontal lobe (Frontal eye fields or superior colliculus)-->
2) rostral interstitial nucleus of MLF -->deccusates-->CN III & IV nuclei; pursuit control is aided by interstitial nucleus of Cajal |
|
Horiz. Gaze
|
PPRF
|
|
Lacrimation
|
parasympathetics (from sup salivatory glands) leave brain w/ nervous intermedius (glossopalatine N) & travel w/ CN7 through Gr petrosal canal & geniculate ganglion (after emerging from canal, now called Gr superficial petrosal N)-->joined by deep petrosal N sympatheticenter pterygoid canal (vidian canal)-->extis canal (now called vidian N) to SYNAPSE in pterygopalatine/sphenopalatine ganglion to join CN V2-->lacrimal gland
|
|
eyelid Layers
|
skin, orbicularis, tarsus, muellers, conj
|
|
Gray line
|
marginal edge of pretarsal orbicularis (muscle of Riolan)
|
|
eyelid vascular supply
|
Internal carotid-->ophthalmic (orbital) artery; External carotid-->facial artery-->transverse facial artery-->angular & malar branches
|
|
Medial canthal tendon
|
anterior—attaches to frontal process of maxilla-->origin of superficial head of pretarsal orbicularis;
posterior—inserts on posterior lacrimal crest & fossa |
|
Orbicularis
|
fxn=lid closure, brow depression, tear drainage; CN7
|
|
orbicularis:
orbital |
anterior limb to medial canthal tendon & periosteum== forced lid closure; superiorly-->continuous w/ corrugators
|
|
orbicularis
Preseptal |
wraps around lacrimal sac & post lacrimal crest; laterally forms lateral palpebral raphe overlying lateral orbital rim
|
|
orbicularis
Pretarsal |
post lacrimal crest & ant limb of medial & lat canthal; medially heads: 1)superficial --> medial canthal tendon 2)deep --> horners tensor tarsi -->inserts @ post lacrimal crest encircling canaliculi to facilitate tear drainage; laterally: lateral palpebral tendon attaches to lateral retinaculum --> atttaches to lateral orbital tubercle of Whitnall
|
|
Corrugators
|
pulls brow to nose -->glabellar skin creases (thytids); frontal bone periosteum-->sub-Q tissue; inferior-->fibers are continuous w/ orbital orbicularis
|
|
Procerus
|
depresses brow; interdigitates w/ inf frontalis--> horizontal lines at nasion & dorsum of nose
|
|
Lymph drainage of eyelids
|
medial upper lid-->submandibular LN;
lateral upper lid-->preauricular LN; |
|
Venous drainage of eyelids
|
pretarsal medial upper lid-->angular V; pretarsal lateral upper lid-->superficial temporal V
|
|
vascular supply to prelaminar region of ON
|
Capillaries from Short post ciliary artery
|
|
vascular supply to Lamina Cribrosa region of ON
|
Plexus from Short post ciliary artery
|
|
vascular supply to retrolaminar region of ON
|
Ciliary (recurrant pial vessels) + retinal circulation
|
|
Cilioretinal artery
|
present in 15-25%
|
|
Central retinal artery
|
surface NFL of ON; provides centripetal branches from pial region; supplies NFL, GCL, IPL, inner 1/3 of INL
|