Term
| components of the posterior segment |
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Definition
comprises about 80% of the eye
orbit
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sclera
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choroid
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retina - macula
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vitreous
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ciliary body |
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Term
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Definition
extends from ora serrata (including pars plana) to the root of the iris
secretory epithelium (ciliary processes) - manufactures aqueous, nutrient fluid
ciliary muscle - control accommodation; contract->zonules loosen->lens becomes more round->more refracting power = see better close up
pars plana - intraocular band within the ciliary body that is devoid of important structures, entry point to back of eye (surgery, injections) |
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Term
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Definition
transparent gel that helps maintain structure of the globe
hyaluronic acid, collagen fibers, dilute saline solution
cortex has firm attachments to the retina and border of optic disc
degrades with age and can detach - floaters or tear retina |
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Term
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Definition
neural inner layer lining posterior eye
nutrient providing retina pigment epithelium outer and sensory inner portions
retinal artery and vein, ganglion cell, bipolar cell, photoreceptors, retina pigment epithelium |
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Term
retina
retinal artery and vein |
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Definition
travel in inner most retinal layer
visible with ophthalmoscope
endothelial cells form the inner of the blood-retina barrier
nourish only the retinal ganglion cells and axons (deeper layers get nutrients from choroidal blood supply) |
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Term
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Definition
| conveys visual signals through the optic nerve to the lateral geniculate body in the thalamus |
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Term
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Definition
| way station in neural pathway from rod and cone to ganglion cells |
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Term
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Definition
rod - transduces light into neural signals responsible for vision in low light situations
cone - photoreceptor that transduces light into neural signals responsible for high resolution and color vision |
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Term
retina
retinal pigment epithelium (RPE) |
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Definition
single layer of hexogonal cells that provides metabolic support to the rods and cones
tight junctions form the outer blood-retina barrier (prevents macromolecules that escape from choroidal vessels from entering the retinal) |
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Term
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Definition
small but critical retinal region containing a high density of cones and ganglion cells specialized in central vision acuity and color vision
central 18 degrees of visual acuity |
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Term
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Definition
central depression within the macula in which the retina consists only of cones; other layers pushed aside
central 5 degrees of vision |
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Term
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Definition
| vascular nutrient layer between the retina and the sclera that contains melanocytes and the highly vascular, but porous, choriocapillaries |
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Term
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Definition
collagenous outer wall of the eyeball
episclera has rich vascular network, covered by the conjunctiva (vascular mucous membrane) |
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Term
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Definition
frontal bone
superior orbital septum
levator palpebrae superioris muscle (CN III)
superior rectus muscle (CN III)
orbital fat
optic nerve
inferior rectus muscle (CN III)
inferior orbital septum
maxilla |
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Term
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Definition
superior and inferior
collagenous curtains that connect frontal or maxilla bone to eyelid tarsus
act as a barrier to inflammation spreading backward from the eyelid |
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Term
| how does one know the pathology lies in the posterior segment? |
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Definition
thorough history
physical exam - visual acuity, penlight, red reflex, pupils
supplemental testing - angiography, OCT, visual fields, electrophysiology, ultrasound, CT/MRI
localization is important for making differential diagnosis that can then dictate the urgency of a referral |
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Term
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Definition
location, PQRST of each ocular concern
common posterior eye symptoms: increased waviness to straight lines, floaters, flashed of light, decreased peripheral vision, sudden onset central burning |
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Term
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Definition
visual acuity = vital sign of the eye
pen light exam - eval eyelids, conjunctiva, anterior sclera, cornea, anterior chamber, pupil; assess for APD
red-reflex gives evidence of a clear ocular media |
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Term
| disease categories for each posterior segment structure |
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Definition
degeneration
inflammation
vascular
infection
neoplasm
trauma |
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Term
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Definition
age-related macular degeneration (AMD)
-wet
-dry |
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Term
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Definition
slowly progressive history
mild burning, waviness
drusen (yellow deposits deep to retina), RPE changes (RPE starts to clump) |
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Term
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Definition
AREDS-formula vitamin (contains zinc)
looking at grid each day to make sure lines don't get wavy
can't stop AMD, but can slow its progression |
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Term
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Definition
less total %age of AMD patients, but 90% of those with severe vision loss
rapid vision loss, waviness/warped vision
subretinal fluid and hemorrhage in back of the eye
blood vessel growth under the retina from choroid leaksfluid |
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Term
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Definition
intravitreal anti-vascular endothelial growth factor +/- laser
photo dynamic therapy |
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Term
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Definition
leading cause of legal blindness
does not cause complete blindness - maintain peripheral vision |
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Term
| inflammation/infection disorders |
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Definition
uveitis
endophthalmitis
scleritis
episcleritis
orbital cellulitis |
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Term
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Definition
basically any inflammation in the eye
classified by the predominant location of the inflammation
periocular pain, light sensitivity, eye redness, decreased visual acuity, sometimes floaters
ciliary flush, white cell infiltrat, aqueous turbidity, vasculitis, virtritis, retinitis, choroiditis |
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Term
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Definition
suspected cases should be referred immediately (bc it is difficult to distinguish the different causes of intraocular inflamation and infection)
comprehensive work up to determine the source
tx with immunosuppression for inflammation and anti-infective agents for infection |
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Term
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Definition
infection inside the eyeball
endogenous or exogenous
rapid onset severe pain, redness, vision loss
severe conjunctival hyperemia, hypopyon, fibrin, viritis |
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Term
| endophthalmitis management |
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Definition
immediate referral
aspiration of vitreous for cultures, empiric injection of broad-spec antibiotics
systemic antibiotics only for endogenous endop. |
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Term
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Definition
focal or diffuse scleral inflammation, often associated with systemic vasculitis and other acute autoimmune disorders
focal/diffuse redness, severe *pain*, scleral thinning (bluish hue)
refer immediately |
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Term
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Definition
idiopathic focal inflammation of deep subconjunctival tissue
present with only mild or *no pain*, resolves spontaneously |
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Term
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Definition
resolves spontaneously
observe; oral NSAIDs, artificial tears
refer is no improvement in 48 hours |
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Term
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Definition
infection around the eyeball posterior to the orbital septum that arises from a skin infection or, more commonly, the paranasal sinuses
pain, lid edema/redness, blurred or double vision
proptosis (eye bulge), reduced movement, visual loss, orbital CT showing infiltrate |
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Term
| orbital cellulitis management |
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Definition
emergent referral for IV antibiotics and possible surgery
in immunocompromised patients, mucormycosis and aspergillosis are life-threatening fungal infections that can cause orbital cellulitis and require immediate referal |
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Term
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Definition
diabetic retinopathy
diabetic macular edema
retinal vascular occlusion
retinal artery occlusion
retinal vein occlusion
HTN retinopathy |
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Term
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Definition
leading cause of blindness in working age-Americans
visual impairemnt from macular ischemia, edema, neovascularization-related complications
referral urgency based of type if DM |
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Term
| diabetic retinopathy referral |
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Definition
referral 3-5 years post-DM type 1 diagnosis, then yearly
referral at type 2 diagnosis, then yearly
diabetic retinopathy begins with a background retinopathy stage |
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Term
| background diabetic retinopathy |
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Definition
often Asymptomatic
microaneurysms, hard (lipid) exudates, cotton-wool spots, intraretinal hemorrhage, venous bleeding
manage by controlling systemic modified risk factors to prevent progression to proliferative diabetic retinopathy |
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Term
| proliferative diabetic retinopathy |
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Definition
neovascularization of the optic disc, retina or iria
fibrous proliferation
blood vessels come up from retinal vessels and grow into the vitreous jelly, can lead to blinding complications (vitreous hemorrhage, tractional retinal detachments, neovascular glaucoma) |
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Term
| proliferative diabetic retinopathy management |
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Definition
| panretinal photocoagulation, virectomy, anti-VEGF injections, continued systemic blood sugar control |
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Term
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Definition
accumulation of intraretinal fluid from vascular incompetence within the macula
present asymptomatically or with blurred vision (if central macula involved)
retinal thickening, hard exudates |
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Term
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Definition
focal laser and anti-VEGF injections
visual acuity difficult to recover once reduced |
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Term
| 3 ways to lose vision with diabetic retinopathy |
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Definition
ischemia
edema
complications with neovascularization |
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Term
| retinal vascular occlusion |
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Definition
can effect arterial or venous system
associated with systemic arteriosclerosis, diabetes, HTN, hypercoaguable states
transient monocular visual loss - sudden, painless
the ischemia is brief and often brief and visual function recovers without permanent sequelae |
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Term
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Definition
from embolism or thrombosis
vision limited by ischemia or neovascular complications
sudden, painless vision loss
retina whitening, *cherry red spot*, Hollenhorst plaque
observation, determine source
refer emergently to have stroke work up (the embolis causing occlusion had to come from somewhere!) |
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Term
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Definition
thrombosis
vision limited by ischemia, macular edema, neovascular complications
sudden, painless vision loss
retina develops countless flame-shaped intraretinal hemorrhages, distended veins, and sometimes cotton wool spots
observation, laser, anti-VEGF
urgent referral (within a week or so) |
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Term
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Definition
severe retinopathy from sudden or massive pressure elevation
spectrum from no visual change to severe vision loss
mild arterial narrowing to retinal hemorrhages and disc edema
tx is BP control! |
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Term
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Definition
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Term
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Definition
malignant neoplasm that can arise from the iris, ciliary body, or chorioid
most common intraocular maignancy in adults (but still rare)
no definite risk factors besides aging
often asymptomatic, but sometimes flashed
diagnosed clinically
plaque radiation, enculeation s big tumor |
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Term
| (pseduo) trauma disorders |
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Definition
posterior vitreous detachment
retinal detachment |
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Term
| posterior vitreous detachment |
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Definition
lifting of vitreous body from insertion of posterior retina
secondary to aging, inflammation, trauma
floaters, flashes
vitreous elevation, hemorrhage, retinal tear (if come off with force)
refer immediately since it shares many of the same symptoms as retinal detachment |
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Term
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Definition
separation of the retina from the retinal pigment epithelium (so can't get its nutrients anymore)
rf: aging, myopia, eye surgery, inflammation, trauma, detachment in other eye, lattice
flashes, shower of floaters, decreased peripheral vision
elevated retinal
surgical management |
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