List I - Core Conditions Flashcards
1
Q
What is a cataract?
A
- Cloudy area (opacity) that occurs within the lens of an eye that can reduce the transparency of the lens
- Cataract may form in one or both eyes at any age
2
Q
What are the causes of cataracts?
A
- Most are caused by ageing and are most common in people aged over 60 year
- Other causes include
- Trauma
- Eye disease - such as chronic anterior uveitis, acute congestive angle closure glaucoma, high myopia, retinitis pigmentosa, Leber congenital amaurosis, gyrate atrophy and Stickler syndrome
- Systemic disease such as diabetes, myotonic dystrophy, NF type 2 and severe atopic dermatitis
- Congenital and developmental cataracts in children
3
Q
What are the risk factors for cataracts?
A
- Family history of age related catarracts
- Corticosteroid treatment
- Smoking
- Prolonged exposure to ultraviolet B light
4
Q
How do patients with cataracts present?
A
- Reduced vision
- Faded colour vision making it more difficult to distinguish different colours
- Glare - lights appear brighter than usual
- Halos around lights
- Diplopia
- Opacities
5
Q
What are the signs of cataracts?
A
- Defect in the red reflex (appears reddish-orange)
6
Q
How are cataracts investigated?
A
- Ophthalmoscopy done after pupil dilation
- Findings = normal fundus and optic nerve
- Slit lamp examination
- Findings = visible cataract
7
Q
How are cataracts classified?
A
- Nuclear = change lens refractive index, common in old age
- Polar = localised, commonly inherited, lie in the visual axis
- Subcapsular = due to steroid use, just deep to the lens capsule, in the visual axis
- Dot opacities = common in normal lenses, also seen in diabetes and myotonic dystrophy
8
Q
What is the non-surgical management of cataracts?
A
- Early stages of disease, age related cataracts can be managed conservatively by prescribing stronger glasses/contact lenses or by encouraging the use of bright lighting - these options help to optimise vision but do not actually slow down the progression
9
Q
What are the surgical management options for cataracts?
A
- Surgery is the only effective treatment for cataracts
- Involves removing the cloudy lens and replacing this with an artificial one
- NICE suggests that referral for surgery should be dependent upon whether a visual impairment is present, impact on quality of life, and patient choice
- Whether both eyes are affected and the possible risks and benefits of surgery should be taken into account
- Prior to cataract surgery, patients should be provided with information on the refractive implications of various types of intra-ocular lenses
- After cataract surgery, patients should be advised on the use of eye drops and eyewear, what to do if vision changes and the management of other ocular problems
- Cataract surgery has a high success rate with 85-90% of patients achieving 6/12 corrected vision (on a Snellen chart) postoperatively.
10
Q
What are the potential complications following surgery for cataracts?
A
- Posterior capsule opacification: thickening of the lens capsule
- Retinal detachment
- Posterior capsule rupture
- Endophthalmitis: inflammation of aqueous and/or vitreous humour
11
Q
What is the NICE guidance regarding decisions for referring a person for cataract surgery?
A
- Base the decision to refer a person for cataract surgery on a discussion with them (and their family or carers, as appropriate) that includes:
- How the cataract affects their vision and quality of life
- Whether one or both eyes are affected
- What surgery involves including the risks and benefits
- How their quality of life may be affected if they choose not to have surgery
- Whether they want to have surgery
(Do not restrict acces to cataract surgery on the basis of visual acuity)
- If the person is being considered for surgery:
- Consider whether the person has the capacity to cooperate with eye examinations, surgery and postoperative eye drop treatment
- Formal preoperative assessment may be required for people with systemic comorbidities and individualised care plans may be required for people with social support at home, disabilities or reduced mental capacity including any that may impair optimal postoperative care and those whose first language is not English
- If referral is appropriate, include the persons most recent visual acuity (measured on a Snellen chart) or a copy of the most recent optometrists eyesight test with the referral
- Provide advice on fitness to drive
12
Q
What is the advice regarding fitness to drive for a person with cataracts?
A
- Advise that all drivers must meet the following standards:
- In good day light be able to read a modern vehicle number plate at a distance of 20 metres
- Visual acuity must be at least Snellen 6/12 with both eyes open or in the only eye if monocular
- Any driver who cannot meet these standards must notify the DVLA
- Advise that group 2 bus and lorry drivers require a higher standard of visual acuity:
- Snellen 6/7.5 (0.8) in the better eye
- Snellen 6/60 (0.1) in the poorer eye
- Where glasses are worn to meet the minimum standards they should have a corrective power lesss than or equal to +8 dioptres in any meridian of either lens
- For people with cataracts it is often safe to drive and they may not need to notify the DVLA
- If there is any uncertainty about fitness to drive - advise the person to contact the DVLA
13
Q
What are the benefits of cataract surgery according to NICE guidelines?
A
- Improved visual acuity
- 95% of people will achieve 6/12 Snellen - meets the UK driving requirements
- Reading glasses are usually needed after cataract surgery
- Improved clarity of vision
- Improved colour vision
14
Q
What are the risks of cataract surgery according to NICE guidelines?
A
- Serious complications occur in around 2%
- Most common post operative complication is posterior capsular opacification
- Consequence of proliferation of remnants of lens epithelial cells.
- Causes decreased visual acuity, blurred vision, or glare
- Occurs gradually, can be corrected by laser treatment
- Other complications
- Posterior capsule rupture and/or vitreous loss 2% cases
- Consequences of posterior capsule rupture include: retained lens fragments in the anterior chamber or vitreous; cystoid macular oedema; vitreus prolapse or traction; retinal detachment; endophthalmitis; elevated intraocular pressure, intraocular inflammation or haemorrhage; corneal oedema; and intraocular lens dislocation
- Corneal decompensation - lens fragments retained in the anterior chamber
- Crystalloid macular oedema - inflammatory fluid in the centre of the retina - usually responds well to topical anti-inflammatories
- Detached retina
- Dislocation of the implanted lens
- Dropped nucleus
- Endophthalmitis
- Floppy iris syndrome
- Raised intra-ocular pressure
- Refractive surprise
- Supraachoroidal haemorrhage (very rare)
15
Q
How should a baby or a child who has suspected cataract be managed?
A
- Urgently refer to an opthalmologist
- Same day telephone referral to a paediatric ophthalmologist is warranted if examination for the red reflex shows:
- Presence of an opacity in the red reflex
- Absence of any reflex
- White pupillary reflex (leukocoria)
- Urgent written referral to the ophthalmologist is recommended if the examination shows:
- Inequality in colour, intensity, or clarity of the reflection
- No detectable abnormality but a parent or carer describes a history suspicious of leukocoria in observation or in a photograph
- Ensure assessment by a paediatrician has been carried out for underlying causes of congenital cataract
16
Q
Who is more prone to corneal ulcers?
A
- Contact lens users
17
Q
What are the features of corneal ulcers?
A
- Eye pain
- Photophobia
- Watering of eye
- Focal fluorescein staining of the cornea
18
Q
What is the alternative name for a corneal ulcer?
A
- Microbial keratitis
19
Q
What is a corneal ulcer?
A
- Infection of the window of the eye
20
Q
What are the possible causes of corneal ulcer?
A
- Bacteria (most common)
- Viruses - herpes simplex or varicella zoster virus
- Fungi
- Parasites - acanthamoeba is a parasite contact lens wearers are more vulnerable to
21
Q
What are the risk factors for developing a corneal ulcer?
A
- Contact lens wearers
- Injuries include foreign and vegetable matter
- Use of steroids
- Use of drugs to suppress the immune system e.g. RA
- Abnormalities of eyelids e.g. lashes turning inwards
- Previous corneal transplant
- Co-existing infection of the cornea e.g. herpes virus
- HIV
- Kidney failure
- Diabetes
22
Q
What is the appearance on slit lamp of a bacterial corneal ulcer?
A
- Necrotic stroma, purulent discharge and hypopyon
23
Q
What is the appearance on slit lamp of a fungal corneal ulcer?
A
- Stromal infiltrate with feathery borders
24
Q
What is the appearance on slit lamp of a viral corneal ulcer?
A
- Dendritic pattern with progressive geography and amoeboid confirguration
25
Q
What is the appearance on slit lamp of an acanthoma (parasite) corneal ulcer?
A
- Stromal infiltrates with ring shaped configuration and hypopyon
26
Q
How should a slit lamp examination be conducted for a patient with a suspected corneal ulcer?
A
1. Eyelid assessment for Blepharitis, meibomian glands dysfunction, ectropian/ entropian, lagophthalmos. 2. Eyelashes assessment for trichiasis/ distichiasis 3. Lacrimal apparatus system assessment for punctal abnormalities, dacryocystitis 4. Conjunctiva assessment for discharge, inflammation, foreign body, papillae, follicle, cicatrization, symblepharon, pseudomembrane, filtering bleb, tube errosion 5. Sclera assessment for any nodule, thinning 6. Cornea assessment for epithelial defects, punctate keratopathy, stromal edema, ulceration, thinning, perforation, infiltrate characteristics (size, shape, location, depth), foreign body, sign of previous corneal surgeries. Fluorescein or rose Bengal staining allow clinicians to identify some organism or underlying cause. For example in cases of viral infections dendritic ulcers are stained with fluorescein and rose Bengal stain. 7. Anterior chamber assessment for presence of any inflammation, look for cells and flare, hypopyon, hyphema
27
Q
What is the main medical treatment for corneal ulcer?
A
- Antibiotic, anti-fungal or antiviral eye drops
* Anti-fungal and Acanthamoeba therapy started only after microbiological evidence in most cases
28
Q
What is the main antibiotic used for monotherapy for bacterial corneal ulcer?
A
- Levofloxacin 1.5%
29
Q
What is the main anti-fungal used for monotherapy for fungal corneal ulcer?
A
- Natamycin (topical)
* Voriconalzole (intrastromal adjunct)
30
Q
What is the main anti-viral used for monotherapy for viral corneal ulcer?
A
- Usually 50% heal spontaneously without treatment
- Topical examples include
- Acyclovir 3%
- Ganciclovir 0.15%
- Trifluorothymidine 1%
- Systemic examples include
- Oral acyclovir 400 mg
- Famciclovir 500 mg
- Valacyclovir 1 gm
- Valganciclovir 900 mg
31
Q
What is the main therapy used for acanthoma (parasite) corneal ulcer (Acanthamoeba Keratitis)?
A
- Combination of
- Propamidine Isethionate (Brolene) 0.1% and Polyhexamethylene biguanide 0.02% can be prescribed at an initial stage
- Combination of brolene and neomycin or monotherapy with chlorhexidine also gives good results
32
Q
What is a stye?
A
- Also known as a hordeolum is an acute localised infection or inflammation of the eyelid margin
- It describes a bacterial infection of a cilium and adjacent gland with local abscess formation, usually caused by staphylococcal infection
33
Q
How is a stye classified?
A
- An external stye (also known as a hordeolum or common stye:
- Appears on the eyelid margin
- Is caused by infection of an eyelash follicle and its associated sebaceous or apocrine gland
- An internal stye (also known as an internal hordeolum or Meibomian stye)
- Occurs on the conjunctival surface of the eyelid
- Is caused by infection of a Meibomian gland (situated within the tarsal plate)
34
Q
What are the risk factors for the development of a stye?
A
- Chronic blepharitis
- May present with eyelid margin inflammation and teleangiectasia, with possible eyelash crusting
- May be itch, irritation and typically soft, oily, yellow scaling around the eyelashes
- Acne rosacea
- May present with acneiform eruptions of the eyelids as well as oedema, erythema and telangiectasia of the lid margin
- Eyes may appear thickened and irregular
35
Q
What is the prognosis of a stye?
A
- Usually transient and self limiting
- Symptoms typically resolve within 5-7 days, once the stye has spontaneously ruptured or been drained
- Recurrence is common if there is underlying blepharitis
36
Q
What are the possible complications of a stye?
A
- Infective conjunctivitis
- Infection of the eyelid margin can spread
- Periorbital or orbital cellulitis
- Infection may spread to other ocular glands or neigbouring tissues (rare), presenting with acute onset unilateral eyelid erythema and oedema which may feel firm, warm and tender
- Orbital cellulitis may present with severe pain, blurred vision, double vision, limited and painful eye movements and proptosis (protrusion of the eyeball)
- Meibomian cyst (chalazion)
- Persistent internal stye may develop into a meibomian cyst which is a chronic inflammatory granuloma due to retained Meibomian gland secretions from a blocked duct situated on the posterior aspect of the eyelid, typically it presents as a painless nodule
37
Q
When should a diagnosis of a stye be suspected?
A
- Acute onset of painful, localised swelling (papule or furuncle) near the eyelid margin that develops over several days
- Symptoms are usually unilateral but may be bilateral
- Eye may water excessively (ephora)
38
Q
When should a diagnosis of an external stye be suspected?
A
- Swelling is located at the eyelid margin (upper or lower)
- Swelling is usually localised around an eyelash follicle
- It points anteriorly through the skin
- Small, yellow, puss filled spot may be visible
- Occasionally, multiple styes involve the entire eyelid
39
Q
When should a diagnosis of an internal stye be suspected?
A
- Swelling is tender and localised on the internal eyelid (although the whole eyelid can be affected)
- It is usually further away from the lid margin compared with an external stye
- On everting the eyelid, there is localised swelling within the tarsal plate
- It may point through the skin or posteriorly through the conjunctiva
40
Q
How should a person with a suspected stye have a history taken?
A
- Ask about unilateral or bilateral
- Timing
- Any previous episodes - is it recurrent in the same location
- Any associated symptoms such as changes in visual acuity, double vision, limited or painful eye movements or red eye which may suggest an alternative diagnosis
- Triggers for symptoms such as application of cosmetics, fragrances, haircare products, or contact lens use which may suggest a diagnosis on contact dermatitis
- Any known co-morbidities or risk factors for the development of a stye such as bleparitis of acne rosacea
41
Q
How should a person with a suspected stye have be examined?
A
- Clinical features of an external (swelling at the eyelid margin) or internal (swelling on the internal eyelid) stye
- It is important to evert the lower and upper eyelid during a full examination
- Clinical features suggesting a complication such as orbital or periorbital cellulitis, infective conjunctivitis, or a meibomian cyst (chalazion)
- Signs of chronic inflammation of surrounding skin (dryness and scaling, lichenification and fissuring) which may suggest an alternative diagnosis such as eczema or blepharitis
- Any atypical clinical features such as distortion of the eyelid margin, loss of eyelashes, ulceration or bleeding which may suggest an alternative diagnosis such as malignant eyelid tumour
