Ophthalmology

Orbital cellulitis
a systemically unwell patient
proptosis
peri-ocular swelling and erythema
tenderness over the sinuses
ocular nerve compromise (reduced vision, impaired colour vision or abnormal pupils)
restricted and painful eye movements
In peri-orbital cellulitis, which usually follows an abrasion, there is no pain or restriction of eye movement
Treatment is with IV cefotaxime until afebrile, then amoxycillin/clavulanate for 7–10 days for peri-orbital cellulitis and for orbital cellulitis, IV cefotaxime + di(flu) cloxacillin together followed by amoxycillin/clavulanate (o) 10 days

Conjunctivitis “Pink eye”
Risk factors: exposure to someone infected, rubbing eyes, contact lenses.
Symptoms:
Marked, diffuse redness
Watery, stringy, purulent discharge
Treatment
Viral
Artificial tears, cool compresses, antihistamines
Bacterial
Erythromycin ophthalmic ointment
Or Polytrim, Azithromycin, Ciprofloxacin
Allergic
Self-limiting
Zyrtec, Claritin

Scleritis and episcleritis
Episcleritis:
itching
a red and sore eye
no discharge
no watering
vision normal (usually)
often sectorial
usually self-limiting
Scleritis:
painful
loss of vision
urgent referral
Management
Corticosteroids or
NSAIDs
Episcleritis
Salmon-pink or red discoloration
Scleritis
Violaceous or purplish discoloration

Corneal abrasion
Causes:
Trauma
Contact lens wear/injury
Infection—microbial keratitis:
bacterial (e.g. Pseudomonas [contact lens])
Neurotrophic (e.g. trigeminal nerve defect)
Immune-related (e.g. rheumatoid arthritis)
Spontaneous corneal erosion
Chronic blepharitis
Overexposure (e.g. eyelid defects)
Diagnosis is best performed with a slit lamp using a cobalt blue filter and flourescein staining
Symptoms:
Ocular pain
Foreign body sensation
Watering of the eye (epiphora)
Blepharospasm
Blurred vision
Management
Check for a foreign body
Treat with chloramphenicol 1% ointment ± homatropine 2% (if pain due to ciliary spasm)
Double eye pad (if not infected)
A 6 mm defect heals in 48 hours

Uveitis (iritis)
Clinical feature
Eye redness, esp. around the edge of the iris
Eye discomfort or pain
Increased tearing
Blurred vision
Sensitivity to light
Floaters in the field of vision
Small pupil
Causes include autoimmune-related diseases such as the seronegative arthropathies (e.g. ankylosing spondylitis), SLE, IBD, sarcoidosis and some infections (e.g. toxoplasmosis and syphilis)
Diagnosis: Slit-lamp examination an increase in the protein content of the aqueous (flare) in the anterior chamber
Keratic precipitates it’s when WBC display on the back surface of the conea.
Treatment
pupil dilatation with atropine drops
topical steroids to suppress inflammation
systemic corticosteroids

Cataract
Causes: advancing age, diabetes mellitus, smoking cigarettes, steroids (topical or oral), radiation: long exposure to UV light, TORCH organisms → congenital cataracts, trauma, uveitis, dystrophia myotonica, galactosaemia
Symptoms:
Blurred vision:
reading difficulty
difficulty in recognising faces
problems with driving, especially at night
difficulty with television viewing
reduced ability to see in bright light
may see haloes around lights
Diagnosis
Reduced visual acuity (sometimes improved with pinhole)
Diminished red reflex on ophthalmoscopy
A change in the appearance of the lens
Management
The removal of the cataractous lens and optical correction to restore vision with an intraocular lens implant

Cataract

Hypertensive retinopathy
Risk factors – increasing age, obesity, family history, alcohol, smoking
Systemic hypertension directly affects the retinal, choroidal and optic nerve vasculature
Diagnosis: fundoscopic exam or digital retinal photography, findings usually bilateral
Treatment: blood pressure control

Retinal vessel occlusion
Central retinal artery occlusion
Sudden loss of vision like a ‘curtain descending’ in one eye
Vision not improved with 1 mm pinhole
Usually no light perception
Ophthalmoscopy
Initially normal
May see retinal emboli
Classic ‘red cherry spot’ at macula
Management
massage globe digitally through closed eyelids (use rhythmic direct digital pressure)—may dislodge embolus
rebreathe carbon dioxide (paper bag) or inhale special CO2 mixture (carbogen)
intravenous acetazolamide (Diamox) 500 mg
refer urgently (less than 6 hours)—exclude temporal arteritis

CRAO and BRAO

Retinal vessel occlusion
Central retinal vein thrombosis
Sudden loss of central vision in one eye (if macula involved): can be gradual over days
Vision not improved with 1 mm pinhole
Ophthalmoscopy shows swollen disc and multiple retinal haemorrhages, ‘stormy sunset’ appearance.
Management
No immediate treatment is effective.
fibrinolysin treatment
Laser photocoagulation may be necessary in later stages

CRVO and BRVO

Glaucoma
Open-angle glaucoma
Gradual increases resistance through the trabecular meshwork
Risk factors: advancing age, family history, black ethnic origin, myopia
Symptoms: asymptomatic, loss of peripheral vision, fluctuating pain, blurred vision, halos surrounding lights (worse at night)
Closed-angle glaucoma
The iris bulges forward and seals off the trabecular meshwork from the anterior chamber
Risk factors: increasing age, female, family history, Chinese/east Asian ethnic origin, shallow anterior chamber, medications (Noradrenalin, oxybutynin, amitriptyline)
Symptoms: severe painful red eye, blurred vision, patient >50 years, hazy cornea, fixed semidilated pupil, eye feels hard, halos around lights, associated headache, nausea and vomiting
Normal IOP 10-21mmHG

Glaucoma
Open-angle glaucoma
Management
timolol or betaxolol (beta blockers)
latanoprost (or other prostaglandin analogue) drops, once daily
pilocarpine drops
dipivefrine drops
brimonidine drops
acetazolamide (oral diuretics)
Surgery or laser therapy for failed medication
Closed-angle glaucoma
Urgent ophthalmic referral
Initial management: acetazolamide (Diamox) 500 mg IV and pilocarpine 4% drops to constrict the pupil or pressure-lowering drops
Surgery: laser iridotomy

Glaucoma

Glaucoma
Investigations
Tonometry (Goldmann applanation tonometry)
Upper limit of normal is 22 mmHg
Ophthalmoscopy
Optic disc cupping >30% of total disc area
Visual fields
peripheral visual loss

Keratitis
Keratitis is inflammation of the cornea
pain, impaired eyesight, photophobia (light sensitivity), red eye and a 'gritty' sensation
Causes: viral (HSV, Herpes zoster keratitis), bacterial (staph), fungal, amoebic (Acanthamoebic keratitis), parasitic (Onchocercal keratitis,)
Treatment
depends on the cause of the keratitis
antibacterial, antifungal, or antiviral therapyantibacterial, antifungal, or antiviral therapy

Blepharitis
Clinical features
Persistent sore eyes or eyelids
Irritation, grittiness, burning, dryness and ‘something in the eye’ sensation
Lid or conjunctival swelling and redness
Crusts or scales around the base of the eyelids
Discharge or stickiness, especially in morning
Inflammation and crusting of the lid margins
Associated with secondary ocular effects such as styes, chalazia and conjunctival or corneal ulceration
The two types are:
Anterior - around the skin, eyelashes, and lash follicles
Posterior blepharitis involves the meibomian gland orifices, meibomian glands, tarsal plate, and blepharo-conjunctival junction
anterior blepharitis—staphylococcal
posterior blepharitis—seborrhoeic and rosacea

Blepharitis
Management
Anterior blepharitis
A systematic and long-term commitment to a program of eyelid margin hygiene
Or apply chloromycetin 1% ointment once or twice daily for 4 weeks and review
Posterior blepharitis
Eyelid hygiene
Ocular lubricants
short-term use of a mild topical corticosteroid ointment
antibiotic ointment tetracycline hydrochloride 1% or framycetin 0.5% or chloramphenicol 1% ointment to lid margins 3–6-hourly
systemic antibiotics: doxycycline 50 mg daily for at least 8 weeks (erythromycin for children
<8 years), or flucloxacillin may be required for lid abscess.

Subconjunctival hemorrhage
A beefy red localised haemorrhage with a definite posterior margin, it is pain free.
Usually causes by sudden increase in intrathoracic pressure such as coughing and sneezing
No local therapy is necessary. The haemorrhage absorbs over 2 weeks.

Hypopyon and hyphema
inflammatory cells in the anterior chamber of the eye.
The most common cause of hypopyon is endophthalmitis.
Blood within the aqueous fluid of the anterior chamber.
The most common cause of hyphema is trauma