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191 Cards in this Set

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1. Central Circular Clouding or PMMA edema OR Sattler’s veil:
a. EPITHELIAL clouding, seen with HARD lenses. Gray haze in center
2. Vertical striae aka Hydrogel edema:
a. Vertical, isolate, wispy lines in posterior stroma when edema is > 6-7%. Seen with extended wear SOFT CONTACT LENS. NO light scattering effect, NO change in VA.
3. Fuch's dystrophy
Stroma folds on itself. Occurs when ENDOTHELIAL cells gradually deteriorate. As more endothelial cells are lost, LESS efficient PUMPING of water occurs out of stroma.
Microcyst edema
Epithelial and ANTERIOR stroma cysts. Asymptomatic. Due to extended usage of SOFT CONTACT LENSES. Show a REVERSED ILLUMINATION. HALLMARK SIGN. Due to greater index of refraction of microcyst than the cornea.

NON reversed illumination: water micro blebs. Due to refracive index of water being less ten that of the surrounding cornea.
Superficial Punctate Keratitis
breakdown in surface epithelium
Fick
First sucessful contact lense fit
Mullen
"corneal lenses"
Obrig and Mullen
PMMA molds!!
Tuohy
plastic lens, first modern lens
Wichterie, Lim, and Dreifus
Hydrogels, soft contacts
Bausch and Lomb
First HEMA
Ocular side effects w/ meds: RAD MOM
Refractive change
Altered behavior
Dry eye
Mydriasis
Ocular Irritation
Miosis
Hard Contacts arePMMA
Soft contacts --> Hydrogels
Rigid Contact lens --> RPG
< 1% wear
85% wear
15% wear
Normal corneal HVIC vs VVID
12 mm
13mm
Lid position
+1 if over limbus
0 if at limbus
-1 is lid is below limbus
Edema od cornea leads to vertical striae at what percent?
>7% swelling.
Keratometry problems
only measure 4 points in central 3mm (2 flat, 2 steep meridians)
Keratometer also assums cornea is spherical.
Rigid lenses
Great optical quality, smaller, mroe oxygen porous!, great for myopia and can be used for othokeratology.
Disadvantage: COMFORT and longer adaptation time.
USE proparicaine
Partialblink/flick blink
Occurs with RPGs. Once lid ishalf way down it touches the lens, becomes irritated, and goes back up ---> LEADS TO DRY EYE and other complications
Major role of endothelium
PUMP to keep fluid out
Types of Edema
CCC
Vertical Striaee
Fuch's
Epithelial Microysts
Superficial Punctate Keratitis
CCC
Central Corneal Clouding ---> PMMA EDEMA!!!
also known as Sattler's veil. HARD KENSES, See gray haze, decrease in VA, also get staining!
Vertical Striae
HYDROGEL EDEMA!!!
vertical, isolated wispy lines in POSTERIOR stroma, visible > 6-7% edema. NO decrease in VA
More edema, more striae
Fuch's Dystrophy
Stroma FOLDS onto itself, endothelial cells DETERIORATE, less efficient at pumping out water --> distorts vision
Epithelial Microysts
Epithelial cysts in ANTERIOR stroma. SEEN IN REVERSED illumination! index of refraction of cyst is greater than cornea.
Superficial Punctate Keratitis
BREAKDOWN OF SURFACE epithelium
Limus --> shows signs of hypoxia
Limbal enjorgement/hyperemia, is the precursor to neovascularization. Causes Dilated vessels and MAST cells to be present
Vessel penetation should not exceed how many mm?
1.5!!!! Or else we have neovascularization
Micropannus
Inflammatory movmenet of blood vseels into corneal tissue --> response to STAPH!
see fan shaped clouding of cornea located at 6 o'clock
Kruase and Wilfring
Supply large volumes of tears
Folliculousis
follicles from viruses: are round, clear, with superficial blood vseels
Papillae
bumpbs on lid CAUSED BY CL! and allergies.
GPC
small to giant papillae of tarsal conj. More frequent in hydrogels
Pinguecula
Pink, fatty tissue, harmless
Pterygium
wing shaped, elevated growth on cornea, contraindication to fit CL, needs surgical remmoval
Micropapilla
Bumpbs on conj, mast cells --> CASES RED EYE
Chemosis
NOT due to CL, but is an allergic reaction
MGD Meibomiam gland dysfunction
Patient will ave dry eye because glands are plugged. Not enough oil in outer layer of tear film --> get excessive evaporation an dry eye.
Ectropion
excessive teaing when puncta is not in place to drain tears
CL is in contact with......
TEAR FILM
90% tear film
10% microvilli interdigitates
Tear film composed of
Mucin layer, Aqeuous layet, Lipid layer
To maintain Tear film neuronally
Need CN 7 for tear secretion
CN 7 for blink (tear clearance)
Closed eye are more _______ than open eyes
Hypotonic --> leads to swelling
TBUT measures
DEYDRATION OF TEARS!!! not how much is produced but how long it takes to remove.
Schirmer test
measures PRODUCTION of tears
Biota of the eye
Usually gram +
Gram - is fron environmental contaminations
CLPU
CL Periperal Ulcer --> gram + bacteria --> S aureus.
CLARE
CL ACUTE RED EYE --> Gram -. Endotoxins
Most common cause of corneal infections
P. aeruginosa
Hydrocurve lenses
HEMA + NVP. Improves wettability. More water= more oxygen, BUT also needs to be thicker because its weaker material
Group 1 Low Water Non-ionic
Less water means less O2 permeability, but it also attracts less debris
Group 2 High water Non-ionic
More O2 permeability, decrease debris attraction. MAY BE THICKER
Group 3: Low water ionic
Less O2 permeabiliy, attracts debris. GOOD FOR DISPOSABLES
Group 4: High Water, ionic
Increase in O2 permeability, attracts debri. Godo for hyperopes or high myopes. Good for replacement lens!!
Silicon hydrogels
LOW water contennt ut high transmissity of O2.
The higher the water content....
the thicker the lens.... decrease transmission.
Old lens were ___ thick
New lenses are _____ thick
.35
.035
Anterior optic zone is no smaller than
8 mm, or it would induse flare
Bread and butter rule
Keep C same and increase diameter, sag increases and lens TIGHTENS
If you increase steepness (decrease BC ) and keep diameter the same, sag increases and lens TIGHTENS
To loosen a lens
decrease Diameter or flatten BC (increase it)
Changing the shape of the back curve of the lens using spin cast
does not make much of a difference for the performance of the lens of the eye
Normal TBUT
above 10 sec
Abnormal neovascularization
1.5 mm or more
Must use effectivity when
power is + or - 4 D
When deciding to go with toric or spheric lenses, you can try spheric if the ratio of sphere to cyl is:
4:1
Soft contact lens
Calculated Residual Astigmatism=
Total Refractive Astigmatism
Rigid Contact Lens
Calculated Residual Astigmatism=
Total Refractive Astigmastism-Keratometry readings
Since its - a minus, you add them
So if the astigmatism is at the cornea=
RPGs are better at solving the problem, because soft contact lenses will just drape over the cornea and not change the shape.
However if the astigmastism doesnt lie on the cornea itself, and the residual astigmastism is internal, you can use a soft contact lens
5 criteria for soft lens eval
MVP CH
Movement
Viscual Acuity
Position
Comfort
Health
Edge standoff
feels like an eyelash to the eye. The edge of the lens flips. Fit the lens to be larger, steepers, and or/ tighter.
Flexing phenomenon
when patient blinks, the cl is pushed up against the cornea and vision is improved. Occurs when a lens is not setttled properly. May need to give patient something flatter
If lens is too loose
We will see excess movement
Superior or temperal superior
if lens is too loose
We will see no movement, inferior position, some flexing
See mires fuzzy, clear, fuzzy
TIGHT fit
See mires clear, fuzzy, clear
LOOSE fit
Eosinophils
allergic
Nuetrophils
bacterial
Lymphocytes
viral
Jelly bumpbs
Cholesterol on lens due to deposits from tears in patient with high cholesterol. Effect VA, seen in torics because they dont rotate
Centrak ounctyate staingin
usually due to tight lenses, especially in HYPEROPES which have thick centers.
Foreign Body Tracks
Can be a one time thing, see geometric linear appearance
SPK Superficial Punctate Keratitis
Usually due to an allergic reaction, dry lenses, or tight lenses.
Prowl line
Shows up in people that do not blink well, see lid deposists that collect on bottom of lens
Arcuate stain
due to bad edge or blend of CL
Inferior nasal stain
Due to bad placement of CL, does not sit well inferiorly, get nasal exposure. Lens can be too small
Superfical stippling
dirt behind lens
Superior Limbic Keratitis
Superior cornea and conj injection, stainging and filtrates.
Seen in middle age women bilaterally.
Contact lens keratoconjunctivivis
Supepithelial infilatres, painl, light sensitivity, edema
Edema is graded from
0-3, 3 being the most severe
% of O2 in air
21%
Closed eye has __________ reduced oxygen supply
2/3
21% of 760 mm Hg=
155 mg Partial Pressure of Oxygen in on CL patient

In aspin, the oxygen is 15%!! --> 137 mg
RGOs get 1-3% oxygen from
tear pumping mechansim.
SCL ONLY gets oxygen thru transmition
cornea needs ____ oxygen tofunction properly
2-5%
Equivapent Oxygen Percentage EOP
equals the concentration of O2 in gaseous mixture that induces an equvalent oxygen thrist of the cornea. An open eye needs 10% or more oxygen to prevent edema
Normal eye consumption rate is ___
21%
Critical oxygen for cornea is 2-5% but clincally we want _____ for safe function
8-10%
EOP Equivalent Oxygen Percentage is a _______ measurement
biological
PMMA Equivalent Oxygen Percentage is
0, DOES NOT LET Oxygen in
Permeability is measured in
DK is in barrer
Dk is Diffusion coefficient times solubility coefficient
Dk is
independent of material thickness
DEPENDANT on temperature.
DOES NOT tell you how much oxygen is transmitted, just how well O2 permeates into the lens.
Dk for soft contact lens = water content of lens
Dk/t is Oxygen TRANSMISSIBILITY
It is a LENS PROPERTY and a PHYSICAL test. (EOP was biological)
Measured in barrer/cm
Lens does not have to be worn to determine value
Typically measured at -3 D and 35 degrees C.
Boundary Layer Effect
Reduces effective Dk/t of a lens on eye. O2 molecule arrives at front surface of lens faster than it can penetrate into lens, it thus gets trapped in the interface surfaces
Must measure Dk/t average of entire lens because
lenses are thicker and thinner at different areas depending on type of prescription and power of prescription
RGP Permeability
Gas dissolves thru anterior lens, thru lens proper, thru posterior lens, disolves into poster lens tear film and then fluirinated material
EOP can never exceed
21%
O2 supply via blinking for RGP
15-20% per blink, GREAT tear exchange.
Hyopoxia in epithelium leads to
Decrease in Oxygne flux
weakened hemidesmosomes
Decreases mitosis --> SPK punctate staining
Epithelial thinning
Hypoethesia
Microcysts
Hypoxia in stroma leads to
Edema, thickening
striae and folds (striae at 7% and folds at 10%)
Stroma thinning after long term hypoxia
Vascualrization
Shape/change exhaust

15-20% edema is pathological and leads to endothelial cell damage
Normal swelling of eye with no lens
on average its 4%, deswelling occurs within 90 minutes after eyes are open
Soft lens overnight swelling
4% of normal + 8% due to lens = 12% overnigt
Polymegethism
increase in variability of size and shape of enodthelial cells. IRREVERSIBLE
Mertz Holden Criterion:
SCL Daily Wear
Swelling= 0%
Minimum O2 % dk/t=24.1
EOP 9.9%
MErtz Holden Criterion:
SCL Extended wear
Swelling= 4%
Minimum O2 % dk/t= 87%
EOP= 17.9%
D Value Test
Lower is better --> time it takes to reduce pop of organizsm to 90%
Disinfection
Reduces level of microbio. to safe level --> SPORES survive
Sanitize
Make clean
Sterilize
KILL microbes + SPORES. 121 degree C for 15 min at 15 psi for autoclave
Asepticize
free from disease producing acteria
Pellicle
Micoprotein surface coating. Bacteria adheres and uses it as food.
Emulsify
Good for lipids
Preservatives include:
Dymed,polyquad, sorbic acid, thimersoal
Dymed
Low tox, some absor into matrix
Polyquad
No abs into lens
Sorbic Acid
bacteriostatic, breaks down can can cause LENS DISCOLORATION if used with H2O2.

FOUND IN B& L SENSITIVE EYES
Thmerosal
Combo with EDTA and clorhexidine. Aders to protein deposits. Not used now.
Miraflow
practioners use ONLY. EXTRA strength cleaner
Heat disinfection
fast, cheap, destructive and OBSELETE.

Good for acanthamoeba, effective against FUNGI
Cold disinfection
fast, expinsive, 4 hours to soak
H2O2 disenfection
expensive, bacteriocidal, good for killing HIV, BAD for fungi
Dymded
found in B & L RENU.
Polyquad
Found in Alcon Optic Fre
Thimerosal
antifingunal and microbial. No longer used
Chlorhexidine
biguanide agent. Disrupts lipid layer of cell membranes. Binds to hema. Selcom used
Sorbic Acid
bacteriostatic, breaks down can can cause LENS DISCOLORATION if used with H2O2.

FOUND IN B& L SENSITIVE EYES
Thmerosal
Combo with EDTA and clorhexidine. Aders to protein deposits. Not used now.
Miraflow
practioners use ONLY. EXTRA strength cleaner
Heat disinfection
fast, cheap, destructive and OBSELETE.

Good for acanthamoeba, effective against FUNGI
Cold disinfection
fast, expinsive, 4 hours to soak
H2O2 disenfection
expensive, bacteriocidal, good for killing HIV, BAD for fungi
Dymded
found in B & L RENU.
Polyquad
Found in Alcon Optic Fre
Thimerosal
antifingunal and microbial. No longer used
Chlorhexidine
biguanide agent. Disrupts lipid layer of cell membranes. Binds to hema. Selcom used
Benzalkonium chloride
Gram - and + organizms. ONLY for hard lenses
RENU MULTI-PURPOSE
CONTAINS HYDRONATE--> NONenzyme protein remove
HYDRONATE
--> NONenzyme protein remove
Optic Free Replensih
contains ALDOX kills acanthamoeba
AOSEPT
one step system, neutraizes peroxide into saline
ULTRACARE
Pink colored catalse to clean and neutralzie peroxide
Purilen
UV light to clean
Subtilisin A
Controlled fermentation of Bacillius Lichenformis
Papain
original enzyme, can be ocular discomfort
Pancreatin
enzyme. Optic free- better against lipids and mucoids
Causes of lens discoloration:
Sobric acid, postassium sorbate, thimerosal (blackens), hydropen peroxide (pink), benzyle peroxide (acne med_
Lysozyme
bactericidal against G+
Lactoferrin
bacteriostatic, good against G-loppoly
sIgA
Engulgs by PMN. DECREASES with CONTACT LENS USE --> MORE PRONE TO INFECTION!!!!!!
Complement
30 antimicrobial proeints, leak into tears while sleeping --> lysisis membranes of microbes.
Contact lens wear does NOT affect ______________________
but does effect _______ levels
LYSOZME AND LACTOFERRIN


IgA
EW Dk/t need:
125

Hydrogels: <35
RGP: +100
Ciba Night and Day
DK/t 175
No myopic creep occurs with
silicone hydrogels
Grade Neovasc 1
< .5 mm or 1 or 2 vessles extending less than 1.5 mm from cornea
Neovasc 2
.5-1.5mm into cornea
Neovasc 3
1.5-2.5 mm into cornea
Neovasc 4
> 2.5 mm into cornea or vessel withi 3 mm of corneal apex into visual axis.
NOT DUE TO CL but from disease
epithelial microcysts
Basal layer!! cyst odies. Seen in hyrogel EW. Hypoxia alters epithelial cellular metabolism. Migrate to surface and release debri that stains! REVERSED ILLUMINATION.
IS NOT CAUSED BY SILICONE HYDROPGELS.
INCREASE water content and decrease thickness.
Tight lenses lead 2 two conditions
CLARE Contact lens acute red eye
SEAL Superior epithelial arcuate lesion
SEAL
Superior epithelial arcutate lesion:
MECHANICAL complication with soft CL. edge rubs onto cornea. See arcuate epithelial lesion, ac like grayis white epithelial lesion, heaped edges, inflitration, staining.
MAY BE MORE PREVELENT in SILICONE HYDROGEL due to higher higher rigidity
give antibiotic to treat
CLARE
Contact Lens Acute Red Eye
Usually unilateral
Bulbar injection
pain
lacrimation
photophobia
no staining
TIGHT fitting soft lens with tapped debri --> tight lens syndrome
possible guttata
Starts at NIGHT
infiltration in peripery and mid periphery
give Fluroquinolone to protectagaint GM-
Reduced rates with silicone CL
CLPU
Contact Lens Peripheral Ulcer-
anterior stromal infiltrate with full thickness epithelial defect
WHITE SPOT ON EYE
mild irritation
ocular redness
localized limbal/bulbar injection
small
scar, fade after 6 months
WILL NOT CULTURE: noninfectious

decreased rates with silicone
Phlyctenulosis
delayed sensitivity to staph toxin
seen with chlamidyia and TB
ELEVATED WHITE LESION
contains eosinophils. Treat with Tobradex
CLPC
Contact Lens induced Paillary conjunctivitis:
GPC
Ropy muscuous disscarge
itchness,blurry vision, scarring, tarsal redness, papillae, conj edema and ptosis. Mast cells, eosinophils, IgE.
Grade 1: mild itchiny, no papil
Grade 2: mild lens awareness, mucus, tarsal hypermia
Grade 3: larger papillale >1 mm with infiltrates
4: Severe mucus, large pailallie, staining and infilatres, lid edema.
TREAT grade 3 and 4 with Patanol and steroid (Lotexma)
Microbial Keratitis
Loss of epithelial and stromal tissue due to invading bacteria. Chronic hyopxia LEADS TO IT!!!!!
5 fold increase with extended wear cl.
Decrease risk with silicone.
DUE TO P AEURGINOSA!! Gram -. Sometimes also due to Gram + Staph and Strep

P auerg: Gram -, also responsible for inflammation with CLARE due to ENDOTOXIN!! See Hypophon --> cells in clare in anterior chamber. have pain, redness, photobia, mucpurlent discharge, blurry vision, lid swelling, large lesions, cells in falre, eyelid edema. GIVE FLUORQUIN. 1 ggt 5 x 30 min/2 gt q 15 min x 6 hr, 2 gtt q 30 min x 18 hrs, 2 ggts h thereafter for 14 days.
Acanthomeiab keratitis
Rare funal painful an potentially blinding infection
Non infection ulcer versus infectious ulcer:
Sterile has:
smaller lesions,
more peripheral
less epithelial damage,
NO discharge,
less pain and photophiba
NO AC reaction
NO lid involvement
Infiltrative Kertisis
acute inflammation with prescence of intraepithelial or subepithelial infiltrates.
Caused by bacterial toxins from Gram -.
STARTS DURING THE DAY. Mild irriation, redness, tearin, NO discarge. See periperal intra/suepitheial infiltrates, rarely see scars, no AC reactions. Use steriods
Empirical Method for torics
Patients Rx is orderedWhy do toric Hyodrgels mislocate?
NATURAL vector fores of the lids.
The lids squeeze thin parts of lens. Since prism is usually at 6, the upper lid pushes on the thinner top.
Vector foces lens to move towards nose --> spins lens.
Thicker portions of lens moves towards nose.
Thickness of Axis toric lens
Oblique axis is HARDEST to stabalize!!
Truncated Lens with Prism
NOT used anymore. Increased thickness and sharpe edyes of lens. Made it even more uncomfortable, saw central corneal thickness withing one hour of wear
Prism Ballast
Used toda. Decreses but does not eliminate rotation. Adds BD prism to lens. GRAVITY does not play a role, but rather the WATERMELON principle does.
Apex on top of lens moves lens down and pushes it against globe.
Watermelon Seed Principle
Controls movement of CL!!
GRAVITY does nothing.
Upper lid squeezes on thin lens and pushes it down onto lower lid.
Prism Ballast examples:
B& L Optima --> Front toric lens.
3 Laser marks 30 degrees away.

CSI Toric--> solar. BACK toric.
3 laser marks. Center laser mark is larger.
Thin Zone Design --> Dynamic Stabilization
Ciba Vision Torisoft.
Double-slab off design and lower edges are equally thin.
NO INDUCED PRISMATIC EFFECT NO PRISM
Works great for ATR and HIGHER myopes.
Double slab off
Periballast
No prism!!!! But Ballested. Great for high cyl and obliques.
Eccentric lenituclarization
Lens optics are not exactly centered.
Back toric!
UNIFORM edge thickness--. CYL DOES NOT EFFECT ROTATION.
cyl is all found in center of lens.

Change in RX does not affect lens orientation.
Combo toric lens examples
Durasoft Optifit Toric -->
20 degrees between lenses

Ocular Science Biomedics 55 Toric --> FAVORITE. 2 week disposable toric.
Isoballasting --> uniformly thin 360 degrees around.
Lathe Cutting/Crimping
Original method of creating toric. Dry procedure. not very good and pretty expensive
Stock Lenses
Standard lens rady to be shipped. cyl power= .75-2.50 D
sph: 0-6 D
axes: with 10 degrees