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GLOCKTOMETRY > AE > Flashcards

AE Flashcards

1
Q

Type 1 ocular allergy response phases and mechanism?

A

1) Sensitization phase, Early phase, Late phase
2) pollen antigen binds to igE b cell and Th2 cell

Initial response) igE antibody binds to mast cell, primary and secondary mediator release, vasodilation, vascular leakage.

Late phase) Eosinophil activated by TH2 and Mast cell, releases granules, leukocytes, mucous secretion, mucousal oedema

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2
Q

Mast cell responses and what they cause

A

mediator is histamine

Vasodilation (redness) -prostaglandins, leukotrines, platelet activating factor

Increased permeability (swelling) -prostaglandins, leukotrines, platelet activating factor

Nerve stimulation (itching)

epithelial cells - recruitment of additional inflam cells

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3
Q

Classification of allergy (conjunc)

A 
Allergic conjunctivitis (seasonal, perennial)
Vernal keratoconjunctivitis
Atopic keratoconjunctivitis
giant papillary Conjunctivitis
contact and drug induced allergy
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4
Q

Pharmaceutical treatment of allergic conjunctivitis

A

Mast cell stabilizers - competitive antagonist against IgE to mast cell surface. Prevents degranulation

Anti histamines - competitive antagonist of histamine receptor on vessels, nerves and epith cells. Prevents mast cell degranulation
10 min action

Dual action meds combine them both
vasoconstrictors reduce redness and swelling but combined with antihistamine

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5
Q

Seasonal vs Perennial Allergic conjunc

and treatment

A

S) season, grass. pollen. etc
treatment) monitor levels and choose when, close fitting sunglasses, wash hands

P) All yr, dustmites
treatment) wash bedding reularly 60 deg, clean all areas, dehumidifier

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6
Q

Allergic conjunctivitis (signs, sx, treatment)

A

Signs) lid swelling, mucous discharge

sx) itchy eyes, burning, watery eyes, photophobia
treatment) steroids or sodium cromoglycate

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7
Q

Giant Papillary conjunc. Cause, signs, sx, treatment

A

mech and chem irritation, usually CL wearers with deposit build up

Signs) conjunctival hyperaemia, mucous, thickening and opacification of palpebral conjunctiva w larger papillae

sx) itching on lens removal, blurring of vision, CL intolerance

Treatment) rigid lens/soft enhanced with more wetability, dailies, if unresponsive then Mast cell stabilizers

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8
Q

Vernal Keratoconjunctivitis who, signs and sx,

A

bilateral, usually males (3-25yrs) , warm climates

signs) large papillae in palpebral conjuncitva, sight threatening
sx) itching, photophobia, pain

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9
Q

Atopic Keratoconjunctivitis, who and signs

A

sight threatening, teenagers to early 20’s, FOH atopy, atopic dermatitis

signs) thickened eyelids, flattened velvety papillae, bleph

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10
Q

Treatment for Vernal and Atopic Keratoconjunctivitis

A

Steroids - block release of enzymes which release prostaglandin and leukocytes
SE - cataract, iop elevation

NSAIDs (non steroidal anti inflam drugs) - inhibit cyclooxygenase, no prostaglandin production
CI) asthma
can delay corneal healing

Immunosuppressants against T lymphocytes
cyclosporin 2%

in untreated, blinding

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11
Q

Contact ocular allergy (cause, explanation, differential diagnosis)

A

contact dermatitis + drug induced allergic conjunctivitis

Hypersensitivity because of chemicals. eg cl sol, pilocarpine

sunlight expose - photocontact dermitits

DD) Viral/bacterial conjunc

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12
Q

Types of keratitis (Red eye)

A

Bacterial, Fungal, Viral,

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13
Q

Bacterial Keratitis, factors causing and appearance

A

Factors - DE, Entropion, CL, corneal abrasion, steroid use, decreased vision

appearance - staphylococcus cause white oval infiltrate/ulcer around iris

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14
Q

Fungal Keratitis, how?

A

Trauma w vegetable matter, yeast keratitis affects cornea with pre existing disease

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15
Q

Viral Keratitis, how?

A

Adenovirus,
Herpes simplex direct transmission through secretion,
Herpes zoster may involve trigeminal nerve

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16
Q

Peripheral corneal ulcer types

A

Marginal, Moorens, system disorder

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17
Q

Bacterial Conjunctivits sx

A

sx - gritty, sticky, mucous discharge.

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18
Q

Viral Conjunctivitis sx, and what it can lead to.

A

Bilateral, watery, follicular

1) Leads to punctate keratitis
2) Sub-epith opacities
3) anterior stromal infiltrates

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19
Q

Inclusion Conjunctivitis sx, what it leads to, treatment

A

chlamydia, large follicles near limbus,

1) Can lead to superior epithelial keratitis
2) sub epith infiltrates

treat with tetracycline

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20
Q

Trachoma, cause, process, treatment

A

carried by common fly, follicular reaction in upper lid

blindness by conjunctival, corneal, eyelid scarring

tetracycline treatment and lid/corneal surgery

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21
Q

Episcleritis, what is it, types, sx, treatment

A
  • inflammation of episclera
  • nodular or diffuse
  • unilateral redness and discomfort
  • topical steroids if severe

discomfort rather than scleritis pain

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22
Q

Scleritis, types, associations

A

Anterior, Posterior, Scleromalacia

-assoc - herpes zoster, gout, Crohn’s, erythmatosus

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23
Q

Ocular protective system (from foreign bodies)

A 
Surrounding anatomy
orbital fat
eyelashes/lid
tears to wash away
corneal structure
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24
Q

Classifying a foreign body

A 
Metallic/non
Embedded/Superficial
Penetrating/non
solid/L/G
slow/fast projectile
small/large objects
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25
Q

Symptoms of a foreign body and metal FB

A 
photophobia
lacrimation
blepharospasm - lids shutting tightly
acute pain - sudden pain
hyperaemia - redness
reduced vision

Metal can cause rust ring and can enter globe

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26
Q

Slit lamp procedure for FB

A

DIffuse, sclerotic scatter, direct, indirect, retro, optic section

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27
Q

Blow out fracture, Features

A

1) Posterior displacement of globe by object
2) orbit fractured at weakest pain
3) soft tissues herniate into maxicillary sinus

Features - enophthalmos, eye elevation reduced, loss of sensation

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28
Q

Photokeratitis, sx, Welders flash

A

UV exposure
FB sensation, photophobia,
lacrim, blepharospasm, reduced VA, hyperaemia

WF - bloodshot, acute onset arc eye from uv exposure, symptoms gone by 48hrs

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29
Q

alkali injuries, how and compared to acid

A

1) loss of corneal epithelium
2) clouding/oedema
3) ischaemia of blood vessels
4) neovasc
5) glaucoma

acid is better as self limiting coagulation of surface

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30
Q

Treating Foreign body

A

advice - protective eyewear
irrigation - wash
therapeutics - if epithelial, broad spectrum antibiotics

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31
Q

Foreign Body removal and Surgery

A

Removal - Cottonbud, anaesthesia, rust ring removed with needle

Photo- therapeutic keratectomy

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32
Q

Pterygium - what is is, who?

A

grey opacity at nasal limbus, can be temporal
conjunc overgrows cornea in triangle shape

hot climate

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33
Q

Scleral lenses, what are they?, when did they come about?, why use them?, downside

A

1) lens extending out of sclera, hard lenses 14mm+
2) First type of CL, glass shells 1888, poor oxygen and repeatability
3) Keratoconus, pellucid marginal degen, post corneal trauma, post keratoplasty, post lasik, protective
4) uncomfortable, some eyes too hard to fit and can get dust under lens

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34
Q

Modern history of scleral lenses (PMMA)

A

1) PMMAs introduced in 1900’s
2) tailored to eye shape, still not reproducible
3) RGP material from the 1970’s

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35
Q

Types of scleral lens and how it is fit

A
  • Full 18-24mm
  • Mini 15-18mm - vault cornea entirely (doesnt touch cornea or limbus, lands on sclera.
    Fit odd shapes, protect, minimalize scarring)
    Fitting sets used and calculated from topography
  • Semi 13-15mm
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36
Q

Scleral lens insertion and removal

A

1) px looks down and holds lower lid
2) practitioner holds upper lid and inserts with other hand
3) record rotational axis stability

1) massage inferior bubble
2) scissor technique
3) DMV 45 plunger

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37
Q

Specification required to for toric mini scleral lens

A
  • sag
  • power
  • over refraction
  • mod to limbal fit and scleral landing
  • axis of rotation markers
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38
Q

Care products

A

Soft lens solutions
no preservative saline
alcohol cleaner if necessary

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39
Q

Obstacles to successful wear of scleral lenses and how to overcome

A

1)Conjunctival prolapse - conjunc sucked up under lens. Harmless, when limbus over vaulted, choose lens diameter appropriately.

2)Deposits - front (leads to poor wetting) or back, can be hard to clean well when steep. Use progent
.
3)Excessive settling back - large lens, larger landing zone to spread weight more evenly

4)Fogging - fluid reservoir cloudy after a few hours, px remove and refil, worse in first month.
Due to lipids, use non preserved saline, closer fit, change ratio of artificial tear to saline

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40
Q

Early and Modern Orthokeratology and why?

A

E - conventional hard lens, flatter over time and daytime worn. 1,2D myopia, unstable fit

M - Accelerated, overnight and reverse geometry lens for stability. Full correction attempted w first pair.

W - decrease progression by 45%
–>reversible - corneal thickness recovers fully after one night of no lens wear, curvature after a week, rx UVA after 2 weeks

  • ->convenient, unaffected by dry eye, myopia. No lenses lost in day, can go swimming etc, cleaned in morning when more awake
  • ->management,
41
Q

ORTHO-K LENS DESIGN

A

OVERALL D - 10.50 to 11mm, 360 degrees fit in periphery to allow even fit across distribution zone

Central zone - 6mm D, K(flat) - Rx

Fitting zone - Reverse curve (very steep, bring CL to cornea), approx 0.6mm, adjust to improve centration

Alignment zone - 1mm, responsible for centration, and channel for tear film forces

Peripheral zone - 0.4mm radius 11mm

42
Q

Corneal toxicity and Ortho - k

A

Back surface peripheral torics
limbal to limbal astig
usually when cyl is over -1.50DC

43
Q

How does ortho K work?

A
  • Flattens central cornea without touching it.
  • Redistributes corneal tissue instead of blending
  • may not be plano
44
Q

Who does ortho k work for?

A

Rx - Best for myopia -1 to -5, with the rule corrected up to -2.50DC. Against the rule up to -1.00DC

Corneal health - Keratoconus, scarring, LASIK, DE, anterior segment disease, abnormal topog

Systemic diseases - Diab reduces corneal sensitivity and healing

Lifestyle - convenience of not wearing in day
, patient expectations. Not for OCD BRUDDAS

45
Q

How to fit Ortho K? types and fluoro

A

Fitting set/inventory

  • initial trial fit
  • from inv stock
  • no topographer
  • NaFl assessment

Empirical

  • No trial fit
  • custom made
  • less chair time
  • trouble shooting included

Fluoro

  • open eye, not closed
  • lens
46
Q

Ortho K After Care visit and what is a good result.

A

1st visit - visit after 1 night - (impression, slit lamp, va - expect 2D reduction, slower with astigmats, residual refraction, topography.
possible glare

2nd visit - after 5-7 night - impression, unaided va, slit lamp, topog, subjective

3rd visits - after 10-14 nights - impression, unaided va, slit lamp, topog, subjective

Good result - comfortable over night, happy with vision, minimal staining, topography shows well centred

47
Q

Topography - Ortho K

A

Bullseye - good outcome

DECENTRATION -

  • Smiley face - high riding (WTR astig), Increase sagittal depth.
  • Frowny face or- low riding, decrease sagittal depth.
  • Central - central island pattern. sagittal depth too high so decrease it
  • Lateral Decentration - too small, choose larger diameter
48
Q

Specialist CL types, px who may require, poor VA

A

Bandage CL - after LASIK, thin and plano hydrogels worn for 3-4 days constantly. Allow epithelium to convalesce.

Therapeutic CL - Drug delivery in glauc/dry eye. And some individuals find more comfortable w allergies

Scleral lenses, coloured, post lasik, irreg shapes

Poor VA:
Albino, coloured lens remove light sensitivity as photophobic px

CL telescope system
highpower negative CL, appropriate positive specs lens

49
Q

Advantages of specialist CL

A

spectacle VA inadequate, fitting of conventional poor, better image quality

50
Q

Prosthetic lenses

A

painted lens and shells

  • produce iris/mask scar/hide tropia
  • can be used to mask aniridia
51
Q

Therapeutic CL uses

A

1) form of bandage CL for drug delivery
2) protect against trauma
3) high water content espec after LASIK

52
Q

Irregular corneas and how to check shape

A
  • Primary corneal ectasia - keratoconus, keratoglobus, pellucid MD
  • Recurrent erosion
  • post surgery

Topography as keratometers only do the centre

53
Q

Keratoconus, what, who, treatment, personality, sx, signs, what happens with CL, keratometry, what lenses for treatment

A
  • Collagen disorder, reshaping of cornea into a cone
  • usually bilateral and from FOH
  • HARD LENSES, thickness graft
  • obsessive
  • irreg astig, worsening va, vogt stress lines, munsons sign (v shaped lower lid)
  • reduced tolerance and eye rubbing
  • oval shaped mires >47 dioptres, >1.50D difference between eyes
  • Hybrid CL (soft perm) Soft periph, rigid centre
  • Piggy CL -GP fitted over a soft
  • Scleral CL
  • No7 lens, C3/C4 design, three point touch
54
Q

Corneal warpage

A

changing of corneal shape due to long term hard lens use.
NOT thinning
distorted keratometry mires

55
Q

Spherical aberration, why

A

high positive power of eye,
compensated by periph corneal flattening,
higher R.I. of cornea and lens

56
Q

Nidek OPD, what is it used for and how does it work?

A

corneal topography, wavefront tech

1) retina scanned with IR slit beam
2) reflections captured by photoreceptors
3) aberrations distort reflections

57
Q

Opthonix Z view aberrometer, ft

A

High res wavefront tech

PD, pupillary diameter, internal reading target and internal fixation

58
Q

WestHeimer 1965

A

CL
steep curves, moves with eye, spherical aberration

Specs
shallow curvatures, movement of visual axis relative to eye, astig aberration

59
Q

Embryology

A
  • 3 weeks ->lens placode from surface ectoderm
  • 6 weeks ->lens vesicle
  • 12 weeks ->tunica vasculosa lentis
  • 28-38 weeks ->degen of tunica vasculosa lentis
60
Q

Macroscopic anatomy of lens

A
  • Lens

Diameter - 10mm
Thickness - 4mm
Anterior face radius - 10mm
Posterior face radius - 6mm

61
Q

Microscopic anatomy of lens

A
  • Anterior lens epithelium - single cuboidal layer
  • Lens capsule - basement membrane of lens epithelium
  • Lens Zonules of Zinn - ligament of lens, w collagen fibrils
  • Lens fibres - produced throughout life, parallel to curved surface

-Lens Zones - concentric area of refractive index
subcapsular zone (clear)
cortical zone (newly formed fibres) 1.38
Nuclear zone old fibres 1.40RI

62
Q

Lens composition

A
  • lower h2o content compared to the rest, 64%
  • lens w high protein content, 35%
  • 1%lipid, ph 6.9
63
Q

Lens transparency, losing transparency and UV absorption

A
  • Ordered arrangement of lens fibres, small refractive index difference between materials.
  • Transparency loss - due to: protein aggregation, changes in tissue hydration, break down of membranes, changes in cytoskeletal structure.
  • Lens UV absorption - development of fluorophores and pigment. So discolouration. This protects retina from UV damage. The result is the lens fluorescence.
  • also by corticosteroids, smoking, diabetes
64
Q

Lens aging

A
  • width and density increases with age, 100mg to 250mg
  • radii increases with age
  • yellowing and browning with age
65
Q

Types of cataract, risk factors

A
  • Nuclear - light scattering due to brunescence
  • Cortical - wedge shaped periph
  • Posterior - abnormal epithelial cells

RF - cardiovasc diseas, diab, smoking, low anti oxidants, low socio economic status

66
Q

Referral of lens and calculation

A
  • opacification, no complete cut off
  • when q of life reduced

P= 18 + (1.25 X RX) P IS IRIS SUPPORTED IOL

P = 1336 (4R - L) / (L - C) (4R -C)
R is corneal radius, C is anterior chamber depth
No n of aq/vit, or Rx

67
Q

Types of scan and features

A

A-scan (2D) - interprets echoes from an axial beam, which reflects on intervening structures.
- shows 4 peaks: anterior cornea, anterior lens, posterior lens, retina.

B-scan (2D) - move in arc pattern 40-50 deg, can produce simultaneous A scans.

  • surfaces shown as amplitudes shown as blips
  • no echoes from fluid, blood cells might show tiny echoes.

M-scan - Time motion ultrasonography, look at tissue in realtime to see vascular changes. Similar to pregnancy tech
- follow up for tumours,

68
Q

Couching

A

1) Perforating eyeball with sharp instrument
2) through cataract and into vitreous

However, lens proteins spread in eye, severe inflammation

69
Q

Aphakic IOL (originals)

A

Heavy IOL, corneal endothelium loss, anterior uveitis, posterior capsule sclerosis

70
Q

Anaesthesia, phacoemulsification, limbal relaxing incisions

A

1)

  • 2-3ml lignocaine + intravenous sedative 6%(peribulbar)
    Topical: - amethocaine + lignocaine (anterior chamber)

Comes down to px pref and surgery type

2)

  • Ultrasonic probe inside eye allows lens emusification.
  • Cuts tip into particles and takes in
  • posterior capsule preserved and acts as support for IOL
  • self seals
  • allows efficient removal of lens material
  • utilizes small incisions

3)

  • corneal astig only 15% >2D
  • surgical incision will flatten 0.75 dc on steep axis (more positive)
  • 15 deg per dioptre of experience
71
Q

Post Operation refraction

A
  • check sph-equivalent

- pre-op biometry

72
Q

Nd YAG laser capsulotomy, posterior subcapsular rupture rate

A

Post cataract surgery, posterior subcapsular becomes cloudy.
Rise in IOP, increased risk of RD

Half of all complications,
indicator of surgeon quality, vit loss and RD

73
Q

IOL materials

A

1) Silicone - 1.41-1.46
- flexible, strong, hydrophobic (increases cellular reactions). silicone oil sticks

2) Acrylic (hydrogels) - 1.55
- soft, tendency to stick, reduced rejection

3) PMMA - 1.49 STIFF

74
Q

IOL implants, types, new implants

A

1) round edge
2) square edge
- posterior, anterior, pos with rounded edge

New implants)

  • UV blocking/violet blocking ->AF-1 Hoya
  • Quality ->Thinoptic
  • Astigmatism ->Staar Toric
  • Phakic ->Verisyse
  • Adjustment ->Calhoun vision - 4D vision
75
Q

Micro incision cataract surgery

A

1) Smallest incision size - 1.45
2) less chance for post op complications
3) quicker visual recovery
4) less force on zonules

Lens - akreos MI60, hydrophilic acrylic, 1.8mm incision required

76
Q

Multifocal IOL’s, Diffractive vs Refractive, accommodative

A 
D 
- grating on posterior surface, 
- Light divided between distance and near foci
- reduction in contrast sensitivity
R 
- range of powers on anterior surface
- all light reaches retina
- haloes and slight reduction in contrast sensitivity

Accommodative

1) Hinged optic - forward movement in response to accom
2) Cillary body contracts, vitreous cavity pressure rises, IOL moves forward
3) This movement increases positive power

77
Q

Refractive surgery.
Initial consultation, pre surgery considerations, assess, corneal refraction, contact lens magnification formula, effect on IOP

A

1) leave out cl: (2 weeks soft lenses, 4 weeks hard)
must be stable.

2) VA, cycloRx, VF, AE, fundus, IOP, consent
3) diameter, pachymetry, biometry, topography, tear film quality, muscle balance, amp of accom.

4)
hyperopia - greater accom demand in specs than CL
myopia - less accom demand in specs than CL

5) CLM = 1 – d(m) Fsp d is BVD

6) Reduces IOP, corneal graft raises.
IOP DOESNT CHANGE, THE MEASUREMENT DOES

78
Q

Keratoplasty and types

A

Penetrating corneal thickness grafts, taken from a donor then sutured on

1) Lamellar refractive keratoplasty
- keratophakia - human/synthetic insert
- keratomileusis - removed and reshaped
- Epikeratoplasty - cornea layer scraped away, lenticular placed on top

2)Keratectomy - tissue removed, crescent shape cut out to correct astig

3) Keratotomy - radial patterns cut into cornea for spherical correction, not on axis, weakens cornea, may cause globe rupture,
- radial - radial incisions
- astigmatic - transverse patterns alongside cataract extraction

4)Thermokeratoplasty - heating probe in mid periph, shrinks collagen, central steepening, for hyperopia

  • Nichrome wires - 600 deg for 0.3 sec. Problematic
    as unstable
    -Ho - YAG laser - 55-60 deg, 1-3DS
  • Conductive - radiowaves 65 deg, 0.6 secs.
79
Q

Myopic and hyperopic PhotoRefractiveK, excimer laser keratotomy, how does it work?

A

1) myope - remove tissue to create flattening
hyperope - remove med periph tissue, causing steepening

2)
- Photorefractive keratectomy (PRK)
- insert speculum, anaesthetise, px looks at target, epithelium removed, dry surface bed, zap

> POST OP - VA may be poor due to rx, PAIN,
antibiotics, stabilise, 6-12 weeks
Early complications - mild ptosis, infections, glare,
haloes
Late complications - regression, persistent haze,
irreg topography, recurrent erosion

  • Laser assisted in-situ keratomileusis (LASIK)
    speculum insert, anaesthise, fixate, raise iop to 50, blackout, create flap, dry, zap, replace flap
    >POST OP - flap is repositioned, epithelium grows
    over cut, quick recovery and stability. Less initial
    pain
  • Laser assisted in-situ epithelial keratmileusis or Laser assisted sub-epith keratectomy (LASeK)
    >POST OP - epithelium will gradually be replaced,
    less pain,
    VA quickly stable, stabilise within a month

3)
excimer - break molecular corneal bonds, remove and not burn

80
Q

LASIK procedure

A

1) insert speculum
2) anaesthese cornea
3) fixation target seen
4) raise IOP w suction ring to 50 - 60mmhg
5) CRA blocked so blackout
6) corneal flap (microkeratome) , dry surface, laser, then replace flap

81
Q

Solid state laser

A
  • Higher wavelength, short duration laser
    picosecond (10)-9or femtosecond (10)-12
    -laser to cut the flap via infrastromal ablations
  • femtosecond
    restoring flexibility to lens, so fibres can slide and change shape

Recent developments

  • custom wavefront
  • iris recog software
  • faster eye tracker
  • quicker repetition rate

future
-single unit, changing wavelengths and flapless

82
Q

Munnerlyn Formula

A

t = -(S2 x D) / 8(n-1)

S is the diameter,
D is the power,
T is the thickness

83
Q

Other refractive procedures

A
  • Intrastromal Ring - silicone ring placement PMMA up to -4.50DS
  • Implantable Contact Lenses -
    posterior phakic, implantable CL, periph iriditomy.
    -3 to -20D, +4 to +14
    anterior phakic, iris claw lens
  • Clear Lens extraction
    Cataract surgery, phacoemulsification, higher R.I.,
    foldable and multifocal IOL.
  • Intracorneal inlays - lamellar corneal flap
    1) inlay changing corneal curvature - Rayndrop
    2) inlay increasing depth of focus - Kamra Inlay
    3) refractive inlays, alter refraction index - flexivue
    and icolens
  • Presbyopic surgery -
    • multifocal ablation,
      good - excimer laser, easily enhanced w
      retreatment, can be reversed.
      bad - temp as CL changes w age, corneal
      remodelling, compromised distance vision
    • monovision, - Lasers, IOLs and
    • Thermokeratoplasty
    • Scleral enlongation bands,
      Scleroectomy
  • Scleral surgery
    • Schachars theory - zonules slack and lens bows in
      relaxed position, lens cannot bow further when
      cillary contracts
    • Scleral surgery - inc lens/cillary body distance
      Radial incisions, silicone placed in these, allows
      Cillary Body to shift out
    • multifocal
    • IOL,
    • Accommodating IOL
    • PresVIEW - scleral implant to restore accom,
      outside of visual axis, low SR, no FB sensation
84
Q

DIsorders of the eyelashes

A 
Trichiasis - misdirected eyelashes
Distichiasis - metaplastic eyelashes
entropion - inward rolling of eyelid
ectropion - outward rolling of eyelid
epiblepharon - pretarsal muscle and skin ride above margin
85
Q

Blepharoptosis and ptosis, infections, ocular prutis

A

Blepharoptosis

  • congenital - Levator Dystrophy, Congenital Horners syndrome
  • Hereditary - Myasthenia Gravis, ocular myopathy, systemic myopathy, CPEO

Ptosis

  • History - onset, duration, course, assoc sx, lid surgery, FOH
  • Examination - full ophthalmic exam, lid exam,
    • pay attention to - bells syndrome, lagophthalmos
  • treatment - educating, support groups, botulinum, surgery
 -> Infections
BACTERIAL
- Necrotizing fasciitis
- stye
- chalzion
- Infected Chalazion
VIRAL
- Herpes Zoster
- Herpes Simplex
- Molluscum contagiosum
- Viral Warts

Ocular Pruritis
-Contact Dermatitis (Dermatoblepharitis)
Remove cause, cool compress, MSC, antihistamines, NSAIDS, steroids

-Atopic dermatitis (eczema)
Remove cause, corticosteroids, lubrication of eyelids, Antihistamines and MSC

-Allergic conjunctivitis
Remove cause, specs shields, vasoconstrictors, MSC, anti histamines, NSAIDS, corticsteroids

-Vernal /atopic keratoconjunctivitis
Anti histamines, MSC, steds, supertarsal cortico steroid injection

-Contact lens– induced giant papillary conjunctivitis
discontinue CL, refit CL with MSC, and refractive surgery considered

-Viral conjunctivitis
-Dry eye syndrome
-Blepharitis/ Meibomian gland dysfunction
->DIAGNOSIS
skin patch test

86
Q

Lumps and Bumps BENIGN

A

> Squamous papilloma - sessile or pedunculated lesion, SHAVE IT OFF
Keratoacanthoemeba - horn lower lid, biopsy
Sebaceous - Subcutaneous mass containing desquamated cells and keratin. Surgical excision
Cyst of Moli - benign tumours of sweat glands. fluid filled cyst on eyelid, manage by surgical excision
Capillary haemangioma - benign tumours of capillary endothelium, rapid growth. Beta blockers, corticosteroids,
Port wine stain - malformation, always persists through life, flat pink skin patch, cryotherapy, laser, radiation
Pyogenic granuloma - vascular proliferation, due to irritation or trauma, red mushroom shape, surgical excision
Nevi - pigmented lesion, low malignancy potential, excision biopsy
Xanthelasma - yellow ish plaques, often bilateral, surgical excision, co2 laser, topical trichloroacetic acid
Eyelid Neurofibroma - benign nerve sheath tumour, excision is difficult
Conjunctival Granuloma - granuloma on pos lid surface: chalazia or trauma. SHAVE EXCISION BIOPSY

87
Q

Lumps and Bumps MALIGNANT

A

Suspicious signs of malignancy
- change in size, bleeding, destruction of skin, redirecting/destorying eyelashes, regrown after removed

> Basal cell carcinoma - eyelid tumour
RF - sun exposure
Squamous cell carcinoma - less common,
Sebaceous gland carcinoma - arising from meibomian gland, recurrent chalazoin, bleph,
Melanoma - rare aggressive tumour from melanocytes. change in shape and colour, irregular surface

88
Q

Disorders of the periocular skin

A

> Rosacea - redness of face, inflam of periocular region
warm compresses, eyelid hygiene, drops/ointment, antibiotics, immunosuppressive agents

> Seborrhoeic Keratosis
skin plaques, skin aging, greasy scaling skin patch, medical surgical
Actinic Keratosis - may progress to squamous cell carcinoma, UV induced, thick, scaly, crusty skin patches, excision or cryotherapy

> Bowens diseases - squamous cell carcinoma
persistent brown/red spots, excision or cryotherapy

> Lentigo Maligna - malignant cells in superficial skin, progress to Melanoma. Treatment - monitor, complete excision

>

89
Q

Corneal Diseases, Layers, Congenital clouding,

A

Layers

1) Tear film
2) Epithelium
3) Bowmans
4) Stroma
5) Duas Layer
6) Descemets
7) Endothelium

Congenital clouding
S - SCLEROCORNEA
T - TEARS IN DESCEMETS
U - ULCERS
M - METABOLIC
P - PETERS ANOMALY
E - EDEMA
D - DERMOID
90
Q

Corneal conjunctival conditions

A
  • Microcornea - <10mm, rest of eye normal
  • Posterior embryotoxon - irregular ridge, schwalbes
    ring
  • Sclerocornea - limbus not well defined, severe
  • Dystrophy - primary inherited,
    Epithelial - microcysts, meesmans
    Stromal - granular, lattice, macular
    Endothelial - CHED, Fuchs
  • Map dot fingerprint/ Cogans - epith basement
    membrane, microcysts, subepithelial ridges,
    geographic opacities
  • Keratoconus - cornea thin and protrudes - progressive for 10-20 yrs until 30, Fleishcers ring, vogts striae, Hydrops, munsons sign
    Treatment - crosslinking, rgp, corneal transplant
  • Keratoglobus - entire cornea protrudes, thinning, rupture likely
  • Pellucid marginal degeneration - BI, crescent shaped area of bilateral thinning
  • iridocorneal endothelium disease - iris atrophy and neavus

-

91
Q

Corneal dystrophy types

A
  • Meesmann’s dystrophy - inherited, sx - FB, small grey white opacities

Granular dystrophy - axial, grey opaque granules, good vision until middle age

Lattice dystrophy - branching opacities, early reduction of vision

Macular dystrophy - grey opaque spots with indistinct borders, erosive sx

Schnyder’s dystrophy - opacities from lipids and cholesterol, corneal transplant required

Corneal guttata - First stage of Fuchs dystrophy

Fuch's dystrophy - slowly progression of oedema in elderly. MNGMENT 
Hypertonic 5% NaCl
IOP control
BCL
PKP
  • Vortex dystrophy - deposits in Whorl’s pattern.
    Amiodarone intake, Indomathacin intake, Fabry’s
    disease
92
Q

Corneal degenerations

A

• Lipid keratopathy

  • Arcus sensils - white circle around iris periph due to decomp of fatty corneal materials

• Band keratopathy

  • calcium band caused by: Chronic uveitis, End-stage glaucoma, Phtisis bulbi, Hypercalcemia.
    Treat - surgical debridement
  • Pingueculae/pterygia
  • Salzmann nodular degeneration
93
Q

Acute Corneal disorders

A
  • Dellen - tear film instability, thinning, following strabismus and glauc surgery
  • Corneal abrasions - trauma, pain, red eye, epith loss w fluroescein, give antibiotics, NSAIDS
  • Recurrent corneal erosions - lacrimation, photophobia, brown oedema in anterior stroma, use bandage CL, phototherapeutic keratectectomy
  • Persistent epithelial defects - treat infection, bandage lens, nerve growth factor
  • Epithelial basement membrane dystrophies

Non infective keratitis -

  • Marginal - staphyloccoci ecotoxin cause hypersensitivity reaction, subepithelial infiltrate, mngmnt - antibiotics, lid hygiene
  • periph corneal melt - caused by rheumatoid arthritis, the cornea periph reabsorbs. Give steroids, treat underlining condition and keratoplasty
  • Moorens ulcer - caused by ischaemic necrosis, progressive and painful, steroids, immunosuppressants or chemotherapy
  • Terriens Marginal Degen - bilateral thinning of periph cornea, with neovasc. Lamellar KP treatment
94
Q

Corneal Infections

A
  • Bacterial Keratitis -
    Rf - CL, age, trauma, surgery, meds
    sx - rapid VA drop, pai, photophobia, discharge,
    exam - epithelial ulceration, epithelial oedema, hypopyon
    diagnosis - corneal scrapings, laboratory diagnosis
    management - monotherap = fluoroquinolone
    dual = oflaxicin, penicillin, gentimicin
95
Q

Viral keratitis

A

Adenovirus - follicular conjunc, pain, consider steroids

Herpes - dendritic ulcer - branches ending in beads, stromal infiltrate

Herpes - geographic ulcer - after steroid treatment, consider debridement anti virals

Herpes - stromal keratitis - hypersensitivity, iritis, scarring. Use topical steroids

Herpes - zoster keratitis, VS virus reactivated in ophthalmic division of V-CN
involvement of nose, Hutchinsons signs, bleph and conjunc
stromal keratitis is a sign, uveitis, episcleritis and scleritis
treatment: antibiotics, lubricants, steroids, analgesics for pain

Herpes fungal keratitis - spread deep into AC, fungi able to proliferate in cornea and resist host defence.
RF - improper CL wear, home made saline, swimming, tap water to wash
Acanthamoeba keratitis - ring infiltrates, sclero keratitis, dendritiform lesions
Treatment - multidrug therapy - PHMB, BROLENE, CHLORHEXADINE, TOPICAL STEDS

96
Q

CL ECON

A

20% drop out in first few months

Proactive eye care practitioners - many ECP’s wait for practitioners to ask, but they may be unaware that they are potential candidates
When proactive approach, 6x more new wearers

How to introduce CL:
- profession, sports/theater/sales (eyecontact
better), hot and cold environ fog specs
- high rx specs are bulky
- note previous exp from lenses
- trial pair and benefits
- understand prev experience, address fear and
understand why failed, address expectations

When to introduce

  • H/S, worn before or family
  • offer trial at end, time of spec deliv
  • probe on profession, hobbies, limitations of specs
  • match benefits of CL w Px req

After Care visit Q
- ask how doing, relate to job hobbies etc, feeling after 5 mins, air conn room, cl wetting

  - Opportunity to upgrade
more drops req
eye turns red by end of day
hold mobile further away
husbands reading specs
  • CL correction for Astig
    sph soft, toric soft, RGP
  • CL material - modulus, friction, internal lubrication, oxygen
    permeability, hydration and geometry (thickness
    and edge design)

Disinfecting system
- incompatibilities between SH and preservatives
-

97
Q

Lids and lumps, conditions (Cancers, the rest memorise from PP)

A
  • Basal cell carcinoma - skin cancer, head/neck/eyelid, doesnt heal, telangiectasia
    may be younger px, excision & skin graft req
  • Squamous cell carcinoma - Less common, lower lid, can become deep
    rf - UV - sun, tanning beds, outdoor occupation, smoking, light skin/hair, surgical excision req

BCC VS SCC
B - slow, less blood, little scab, less freq if excision
S - fast growth, bleeds easily, scabs more, freq

 - Malignant Melanoma - 50's, 
rf - sun, complexion, foh, sun sensitivity, poor tanning, freckling
MOLE BECOMING THIS  Signs
 - Asymm shape
 - Border irregularity
 - Colour variation
 - Diam >5mm
Do Biopsy
  • Sebaceous cell carcinoma
    rare, upper lid, firm and small enlarges, rock hard, telangiectasia, swelling, conjunctival hyperaemia, biopsy
    suspect: yellow tumour, eyelash loss, destrcution of meibomian glands, atypical bleph, recurrent chalazion
  • H/S taking
    characteristics, duration, discharge, bleeding/telangiectasia, change in col/size, history of skin cancer
98
Q

Conjunc, episcleral and scleral abnormalities

A
  • Conjunctival hyperaemia - in all conjuc,
    DD perilimbral injection from uveitis
  • Conjunctival Changes - haem, inflam, degen, pigmentation, lumps
  • Subconjunc haem - trauma, venous pressure (coughing), hypertension
    management - careful exam, systemic, referral if ned
  • Conjunctival follicles - lymph follicles, viral or chlamydial.
  • Conjunctival papillae - upper or lower fornix, telengiectasia
  • Conjunctival and pseudo membranes -
    True form - inflam exudate secreted by microorganisms. Tearing and bleeding.
  • Adenoviral, vernal, gonoccoccal conjuc, removed by peeling

-Viral conjunctivitis -
Adenovirus, watery, photophobia, foreign body sensation, Chemosis, pseudomembrane

Chlamydia - prominent follicular response,
non tender preauricular lymphadenopathy

Trachoma - acute - follicles & keratitis
chronic - scarring, pannus
ft - DE, trichiasis, entropian

Allergic Conjunctivitis - hyperaemia, chemosis, mucoid, papillary reaction

  • Atopic - itching, watery, mucoid discharge, vascularisation
  • Vernal - seasonal, itching, watery, mucoid discharge, corneal epithelial defects. Horner Trantas dots, thick limbus
  • Giant papillary conjunctivitis - inflam of conjunc, hypertrophy of superior tarsus, caused by CL

Steven Johnson Syndrome
Acute inflam of skin and mucous membrane
virus and drugs

Conjunctival degenerative conditions

  • Pingecula - conjunctival callouses growing adjacent to cornea 3 or 9 o clock.
  • Pterygium - growth of conjunctiva extending over cornea, by UV light. use sun specs, lubricants, steroids, refer for surgery
  • Conjunctival concretions - FB or calcium lesions
  • Episcleritis - inflam of episcleritis, signs - sectoral injection. Treatment - anti inflam agents, cold compress, monitor IOP,
  • Scleritis - scleral inflam, autoimmune, women, keratitis, uveitis, cataract, glauc, thinning
    sx - very severe pain
    signs - red, assoc with uveitis
    Complications - cataracts, glaucoma, RD
    Treatment - anti inflam therapy
    Anterior - sectorial, nodular, diffuse, necrotising
 - Conjunctival Naevus
modified melanocytes
junctional, compound and subepithelial
inclusion cysts
rarely malignant
  • Racial melanosis
    Benign, non progressive
  • Primary acquired melanosis
    Pigmentation, acquired, beware change
  • Conjunctival intraepithelial Neoplasia
    Localised to epithelium, spectrum of disease, index of suspicious
  • Chemical injuries
    ACID, ALKALI, BLINDING

GLOCKTOMETRY (4 decks)

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