Ophthal Flashcards
What are causes for sudden-onest loss of vision?
- Ischaemic/vascular: thrombosis, embolism, temporal arteritis
- Vitreous Haemorrhage
- Retinal detachment
- Retinal migraine
- Optic neuritis
What is nasolacrimal duct obstruction?
This is the most common cause of a persistent watery eye in an infant. It is caused by an imperforate membrane, usually at the lower end of the lacrimal duct.
-> Teach the parents to massage lacrimal duct. Symptoms should then resolve by age 1 year. If not, refer to ophthal
What is Herpes Zoster Ophthalmicus?
This is the reactivation of the VZV in the area supplied by the opthalmic division of the trigeminal nerve. it accounts for around 10% of cases of shingles.
Features:
- Vesicular rash around the eye, which may/may not involve the actual eye itself
- Hutchinson’s Sign: rash on tip/side of nose -> indicated nasociliary involvement, strong risk factor for ocular involvement
Management:
- Oral antiviral treamtne for 7-10 days
- Topical corticosteroids may be used to treat any secondray inflammation of the eye.
What is the managmetn of blepharitis?
Hot compresses and mechanical removal of debris.
The compresses soften the lid margin. Cotton wool buds (±baby shampoo) can be used to clean the eyelid and remove any debris.
Artificial tears may be given in patients with dry eyes.
What is a stye (give medical term) and also summarise treatment.
A stye, aka hordeolum, is an infection of the glands of the eyelid. (usually caused by staph).
This is treated with regular steaming or warm compress.
What is a chalazion?
A chalazion is a meibomian cyst, usually due to inflammation 2° to gland blockage.
This can often follow a stye, but are painless.
They can get quite big, and remian there for logner than a stye. Still resolve spontaneously, but some may require surgical drainage.
Summarise the main drugs used to treat glaucome and their MoA.
What is the difference between scleritis and episcleritis?
The episclera is the outermost layer of the sclera (the white of the eye). From outer to innermost the layers of the sclera are:
- Episclera
- Stroma
- Lamina fusca
- Endothelium
Episcleritis is not painful, whereas scleritis is painful. Both present with red eyes.
What is Hutchinson’s sign?
Hutchinson’s sign: rash on the tip or side of the nose. Indicates nasociliary involvement and is a strong risk factor for ocular involvement in Herpes Zoster Ophthalmicus.
What are causes of a red eye?
Acute angle closure glaucome:
- Severe pain
- Decreases acuity
- Semi-dilated pupil
- Hazy cornea
Anterior uveitis:
- Acute onset
- Pain
- Blurred vision and photophobia
- Small fixed oval pupil (+ ciliary flush)
Scleritis:
- Severe pain (worse on movement as the muscles insert into sclera)
- Underlying AI disease
Conjunctivitis:
- Purulent discharge if bacterial, clear if viral
Subconjunctival haemorrhage:
- Coughing bouts or Hx of trauma
Endophthalmitis:
- Typically red eye, pain and visual loss following intraocular surgery
What are causes of papilloedema?
- Space occupying lesion (neoplastic or vascular)
- Malignant hypertension
- Idiopathic intracranial hypertension
- Hydrocephalus
- Hypercapnia
What are the three site-specific classifications based on which Horner’s Syndrome can be classified?
How can you distinguish between them?
Summarise the managmeent of conjunctivitis?
- Normally a self-limiting condition, that settles within 1-2 weeks.
- Chloramphenicol drops every 2-3 hours initially/oitment qds daily.
- Topical fusidinic acid in pregnancy
- DO NOT wear contact lenses
- Don’t share towels
What is retinitis pigmentosa
RP is a genetic disorder of the eyes.
it causes:
- Night blindness
- Tunnel vision due to loss of the peripheral retina
- Balck-bone spicule-shaped pigmention on the peripheral retina, mottling of the reinal pigment epithelium
What is the first line investigations for ?orbital cellulitis?
Contrast enhanced CT scan of the orbits, sinuses and brain.
This is to assess the posterior spread of infection.
Other investigations:
- FBC
- Clinical examination involving complete opthalmological assessment
- Blood culutre and microbiological swabs
