6.1.5 Recognises common ocular abnormalities and refers when appropriate Flashcards
What is cataract and what are the symptoms?
Cataract – Caused by denaturation of protein fibrils within the lens due to oxidative
stress, increasing age and metabolic disturbance
Symptoms of a Cataract;
Reduced VA
Reduced CS
Increased Glare
What is nuclear sclerotic cataract?
light scattering associated with Brunescence.
* Poorer Diet
* Low socio-economic status
* Age
* Smoking
* Larger Lens
* Higher Ambient Temperature
Signs:
* Yellowish hue
* Myopic Shift
What is cortical cataract?
Appearance of spokes
* Sunlight (UVB)
* Lens size
* Age
* Diabetes
* Smoking
* Female
* Non-Caucasian
Signs:
* Increased astigmatism
* Monocular Diplopia
What is posterior sub capsular cataract?
abnormal epithelial cells and granular material at posterior pole
due to swelling and breakdown of lens fibres
* Diabetes
* High Myopia
* Steroids
* Age
* Male
* Thyroid Hormone Use
Signs:
Rapidly progressing loss of visual acuity
What is the referral criteria for cataract?
no clear cut off, when sufficient cataract present to limit:
* The quality of life (mobility, glare)
* ability to work
* ability to drive
* willingness to have surgery
College Management Guidelines – ROUTINE Referral
What is the prevalence of cataract?
o 40 – 49 – 2.5%
o 50 – 59 – 6.8%
o 60 – 69 – 20%
o 70 – 79 – 42.8%
o 80 – 89 – 68.3%
o Nuclear Sclerotic – 18.5%
o Cortical – 12.9%
o Posterior Sub-capsular – 10.8%
What is normal tension glaucoma?
- VHG4
- IOPs below 24mmHg
- Visual fields show glaucomatous changes
- Optic Nerve head shows glaucomatous changes
- C:D ratio asymmetry of >0.2 bilaterally
- Loss of ISNT rule
- Notching of the RNFL
- Baring, Bayonetting and Overpassing of the vessels around the optic nerve head
What is primary open angle glaucoma?
- VHG4
- IOPs above 24mmHg
- Visual fields show glaucomatous changes
- Optic Nerve head shows glaucomatous changes
- C:D ratio asymmetry of >0.2 bilaterally
- Loss of ISNT rule
- Notching of the RNFL
- Baring, Bayonetting and Overpassing of the vessels around the optic nerve head
What is ocular hypertension?
- VHG4
- IOPs above 24mmHg
- Visual fields show NO glaucomatous changes
- Optic Nerve head shows NO glaucomatous changes
What is the prevalence of glaucoma?
o COAG - 2% over 40
o OHT - 3-5% over 40
o FHG 4 to 9 times more at risk
What is blepharitis?
Consider DailyDisposable to reduce chances of infection
Grade 3 or 4: Cease lens wear until resolved as risk factor for corneal infection due to
pathological microbes close to ocular surface.
Lid Hygiene:
* Warm compress
* Tea tree oil wipes
* Ocular lubricants
What is MGD?
- Lens wear can be continued if this is tolerated by the px, as more likely to
experience discomfort due to dryer eyes - Artificial tears
- Low water content lens: prevents CL from acting like a sponge and absorbing the
tear film
Describe evaporative dry eye?
Pre-disposing
Factors
* Wind
* Air Con
* Visually attentive tasks where
blink rate is reduced: reading,
VDU
Causes
* Lid Disease: Blepharitis, MGD
* Thyroid eye disease
* Allergic eye disease
Treatment
* Modify local environment
* Lid hygiene
* Omega 3
* Lubricants
Appearance
* Streaky Pattern on Tearfilm
Describe aqueous deficient dry eye?
Pree-disposing factors:
* Medications (Oral,
antihistamines, Betablockers, antipsychotics,
antidepressants)
Causes:
* Inflammation of lacrimal glands
* Sjogren’s Syndrome
* Age
Treatment:
* Lubricants
* Omega 3
* Punctal Plugs
Appearance:
* Circular pattern on tear film
What is dry AMD?
A natural dysregulation of biological retinal processes with time causes a build-up of
waste product generated by the photoreceptors. This product sits between the RPE and
Bruch’s membrane and is called Drusen.
What is the signs of dry AMD?
Dry AMD * Multiple small drusen
* Few intermediate drusen
* RPE pigmentary changes
Intermediate AMD * Extensive intermediate drusen (63-124
ym)
* At least 1 large drusen (>125ym)
* Geographic atrophy not involving the
fovea
At this stage, the AMD may progress into
either Late DRY AMD, or WET AMD
Late AMD * Geographic Atrophy involving fovea
What is wet AMD and what are the signs?
VEGF release causes angiogenesis, triggering neovascular vessels to grow within the
choriocapillaris and through into bruch’s membrane.
These vessels are extremely fragile, causing breakage and subsequent fluid leak of fluid &
blood beneath the macula.
Signs at the macula:
* Drusen
* Hard exudates
* Haemorrhages
* Sub-retinal fluid
* Sub-RPE fluid
* Hyper & Hypopigmentation
