AED: Written Exam Prep [High yield cards only] Flashcards
How thicc is the tear film? Name the layers of the tear film from superficial to deepest, stating how thick each layer is
~7um thick.
Lipid - 0.1um
Aqueous - 7um
Mucoid - 0.05um
What does each layer of the tear film do?
Lipid - stabilizes tear film + reduces evaporation of tears
Aqueous - provides moisture, nutrients, O2 to tissue + removes waste and acts as a flushing mechanism
Mucoid - stabilizing + wetting agent. Anchors tear film to corneal epihtelial cells
How is the tear film replenished with blinking? Describe the mechanism
The meibomian gland produces lipids. The lids close to meet each other. As the lids open again, the upper lid draws up the lipid into a lipid layer. So a new lipid/oil layer is placed on the tear film with each blink.
Name the 4 main ocular allergy presentations
Seasonal conjunctivitis
GIant papillary conjunctivitis (GPC)
Vernal keratoconjunctivitis (VKC)
Atopic keratoconjunctivitis (AKC)
Of the 4 main ocular allergy presentations, which have the potential to be sight threatening?
VKC and AKC
Of the 4 main ocular allergy presentations, what is the key differential for GPC?
Large papillae in a CL wearer
How does VKC vs AKC differ in terms of:
A: onset?
B: sex incidence?
C: seasonal variation?
A: 1st decade vs 2nd/3rd decade
B: Males vs no preference
C: Spring vs perennial
How does VKC vs AKC differ in terms of:
D: discharge?
E: conj scarring?
F: horner trantas dot presence?
D: thick mucoid vs watery clear
E: Moderate incidence vs Higher incidence
F: Commonly seen (incl. shield ulcers) vs Rare (in AKC)
How do VKC vs AKC differ in terms of:
G: corneal neovascularisation?
H: presence of eosinophils in corneal scraping?
G: not present unless 2ndary to infectious keratitis vs generally common
H: more likely vs less likely
Describe the features of Grades 1-4 of GPC
Grade 1 [preclinical] = slight conj redness z fine papillae + no symptoms
Grade 2 [mild] = mild injection, 0.3-0.5mm papillae z mild symptoms
Grade 3 [moderate] = moderate injection, 0.5+mm papillae z increasing CL awareness
Grade 4 [severe] = severe injection, 0.75+mm papillae z lens intolerance
When using steroids for the 4 main ocular allergic presentations. What steroids do you use for each and how often?
Seasonal: FML iBD-iQID (2x-4x a day) for 2 weeks (iQID for one week, iBD for next)
GPC: FML iBD-iQID short term in more severe cases of GPC
VKC: FML/Flarex iBD-iQID
AKC: Flarex/Maxidex iTDS-Q2h with aggressive taper (3xday to every 2 hours)
What symptoms would you expect with an ocular IgE mediated allergic eye disease? (9)
Intense itchiness, “red eye”, conjunctival chemosis (swelling/oedema of conj), blurred vision, mucus discharge, lid thickening, giant or “cobblestone” papillae, limbal infiltrates, SPK, corneal ulcer, etc.
In what general type of ocular presentations would you expect papillae (2)?
Allergic
Bacterial
think “pABillae”
In what general type of ocular presentations would you expect follicles? (3)
Chlaymdia
Toxic
VIral
How can you manage seasonal conjunctivitis? (8)
allergen avoidance,
topical AH/MCS or combos incl.
vasoconstrictors, astringents,
oral AHs,
cold compress,
topical steroids (if MCS don’t work, FML 2wks -> iQID wk, iBD wk)
follow up (px request)
(also topical NSAIDs, topical cyclosporin A, artificial tears)
*(generally since it’s usually mild just try some antihistamines and you’re pretty good)
How can you manage VKC? (7)
Allergen avoidance,
Topical MC inhibitors (patanol iBD, Zatiden iBD), Corticosteroids (FML/Flarex iBD-iQD with follow up one week after),
Topical NSAIDs (Acular iQID),
Topical cyclosporin,
Referral for superficial keratectomy to improve resolution of shield ulcer
How can you manage AKC? (8)
same as VKC but more aggressive steroid use.
Allergen avoidance,
flushing of conj/hypoallergenic bedding,
topical AH/MCS/NSAIDs as per VKC,
Corticosteroids (aggressive. Flarex/Maxidex iTDS to Q2h with aggressive taper) [topical to reduce itch/inflammation], topical cyclosporin,
px must avoid eye rubbing,
follow up regularly and as tx mode dictates (see VKC)
How can you manage GPC? (4)
MCS for several months [if less severe] {patanol iBD, zatiden iBD},
topical steroid short term [if more severe] (FML iBD-iQID),
advise px on CL care, overwear and non preserved solutions,
consider new CLs such as dailies, removal of sutures
When does VKC most commonly manifest?
b/w 5-25yo
Where does VKC most commonly affect?
usually affects superior tarsal conj
In which of the 4 main ocular allergy presentations are patients likely to be atopic?
VKC and AKC
What does the limbal presentation of VKC look like? (4)
Limbitis
Limbal papillae
Horner Trantas dots
Pseudogerontoxon (cupids bow) in area of previously inflamed limbus
Which of the 4 main ocular allergy presentations is not associated with corneal damage of some kind?
Seasonal conjunctivitis
Compare bacterial ulcers with bacterial infiltrate in the following categories:
A: how common?
B: how painful?
C: location?
A: ulcers = rare; infiltrate = more common
B: ulcers = painful; infiltrate = less painful
C: ulcers = central; infiltrate = peripheral (more likely to be peripheral)
Compare ulcers with infiltrate in the following categories:
D: how does the staining compare?
E: AC reaction?
D: ulcers = staining mirrors infiltrate; infiltrate = staining smaller in size than infiltrate
E: ulcers = AC reaction present; infiltrate = no ac reaction
Compare ulcers with infiltrate in the following categories:
F: conjunctival reaction?
G: number of lesions?
F: Ulcers = generalised conj reaction; Infiltrate = sector conj reaction
G: Ulcer = single lesion; Infiltrate = sometimes multiple
In specific terms, how do you treat bacterial ulcers? (4). Which tx is the gold standard?
Freq. dose Ocuflox/Ciloxan (if small otherwise)
Dual fortified antibiotics [Gold std.]
Cefazolin 50mg/ml + Gentamycin 15mg/ml OR tobramycin 15mg/ml alternate each drop q1h
If above fails: lab testing to reveal bac. Resistance than Vancomycin 25mg/ml instead of cephazolin
If meet “1-2-3” guideline: Monotherapy z Fluoroquinolones 2 drops every 15 minutes for 6 hours 2 drops every 30 minutes for 4 hours until resolution
What is the “1-2-3” guideline? What should you do if an ulcer doesn’t meet this criteria?
“1” = 1+ or less cellular response AC; “2” = infiltrates 2mm or less in diameter; “3” = ulcer at least 3mm from visual axis. If ulcer doesn’t meet criteria or no improvement in 24 hours —> refer
How do you treat bacterial infiltrates? (2 basically)
If marginal (CL wear): Stop CLs, monitor, antibiotic [depend on cause. If infection], steroid [if infl], combo,
If bleph assoc. infiltrates: tx bleph, tx cornea z steroid z potential antibiotic cover, if no improvement consider oral doxy
Should you patch bacterial corneal ulcers? Explain
Never patch [creates env. for replication
In simple terms, what is the treatment for a bacterial ulcer?
Fortified antibiotic or fluoroquinolone
Compare Infectious vs Non-infectious ulcerative keratitis in the following categories:
A: Pain/redness/discharge
B: Association with CL wear
C: Location
A: More vs less
B: Assoc. vs Not assoc.
C: More central vs more peripheral
Compare Infectious vs Non-infectious ulcerative keratitis in the following categories:
D: Level of infiltrate
E: Level of AC reaction
D: More infiltrate vs Less infiltrate
E: Significant AC reaction vs mild or no AC reaction
When in doubt, how should you treat ulcerative keratitis?
treat as infectious
What are the signs of EKC? (9)
Acute onset
Unilateral, follicular conjunctivitis z ipsilateral node
Often becomes bilateral
Haemorrhagic conjunctivitis
Pseudomembrane or membranous conjunctivitis
No respiratory involvement
Watery, uncomfortable eye
Conjunctivitis 1-2wks
Corneal involvement (fine SPK from onset. Epi. Opacities at 7 days. SEI at 14 days; SEI persistent!)
What are the signs of PCF? (7)
Follicular conjunctivitis
Often bilateral
Often preauricular lymphadenopathy 3-4 days after onset
Eyelid oedema
May have pseudomembranes
May have keratitis (30% cases) incl. diffuse SPK + subepithelial infiltrates [rare in pCF]
What is the DDx for PCF? (4)
EKC, molluscum contagiosum conj., allergic conj., topical drug hypersensitivity
How can you manage EKC (during infectious period) (4)
If infectious period: supportive (vasoconstrictors, cold compress);
povidone iodine?;
cidofovir in future;
steroids maybe but not really? (prophylaxis/SEI Flarex BD to QID z slow taper
Also: Prevention: in office hygiene/sterilisation; px education
What can you additionally do to manage EKC (post infectious period)? (1)
If post-infectious period: STEROIDS useful in reducing SEI and improving VA
When would darryl use steroids in the management of EKC?
[Timing of steroid use = key to management of EKC!!] “I use steroids after infectious period is over” – Darryl Guest
How can you manage PCF? (7)
Optom hygiene + educate px
GP referral (to stay home)
Contagious for ~2/52
Povidone-iodine?
No antiviral agent proven effective
Palliative: cold compress, artificial tears/irrigation, relief of pharyngitis + fever (z Nurofen)
Steroid if severe inflammation [Flarex BD to QID z slow taper]
When would you follow up a patient with PCF? What should you monitor here?
Follow up: resolves usually in 7-14 days so see in this timeframe. Monitor for corneal involvement. May need topical steroid.
What are SEI?
SEI = sub-epithelial infiltrates = pale little islands of WBCs that are recruited by the limbus to reach the stroma
