Opthalmology Flashcards
Most common form of blindness worldwide?
Cataracts
3rd most common form of blindness worldwide?
Age related macular degeneration
What aspect of vision does ARMD affect?
Central
What aspect of vision does Glaucoma affect?
Peripheral
3 features of dry ARMD
1) Drusen - waste products from pigment eipthelium
2) Atrophy of retinal pigment eipthelium
3) Slowly progressing
4) Less dramatic
3 features of wet ARMD
1) Fluid build up 2’ o neovascularisation from pigment epithelium
2) Haemorrhages, scarring, swelling
3) Dramatic
Presentation of ARMD
Central vision affected, difficulty reading fine print and recognising faces
Signs of ARMD of fundoscopy
Drusen, atrophy, haemorrhages, scarring, pigmentation
Risk factors of ARMD
Smoking, sun exposure, age, poor diet + alcohol
What is the 2nd leading cause of blindness worldwide
Glaucoma
Glaucoma presentation
Usually no symptoms until end stage - bumping into things, missing object in peripheries.
VA unaffected until end stage
Signs of glaucoma on fundoscopy
Cupping, pallor, splinter haemorrhages in optic disk.
Usually raised IOP + RAPD is asymmetric advanced glaucoma
Pathology in AACG
Physically obstructed anterior chamber angle stops outflow of aqueous humour - rise in IOP
What produces the aqueous humour and where does it drain?
Produces - Ciliary body
Drains - Trabecular meshwork
ACAG presentation
Severe and rapid onset of pain
Blurred vision, coloured haloes, systemic malaise
Signs of ACAG
Red eye caused by ciliary flush
Raised IOP, shallow anterior chamber, corneal epithelial oedema
ACAG treatment
Medical - B-blockers, steroids, IV Acetazolamide - if no response then systemic hyperosmotics
Surgical:
- Peripheral iridotomy - 2 holes in iris with laser
- Surgical iridotomy - more invasive when PI not
possible
- Lensectomy - if cataract swollen to precipitate
ACAG
What is GCA
Systemic immune mediated vaculitis affecting medium and large arteries
Presentation of GCA
Recent temporal headache, myalgia, fever, malaise.
Sudden bilateral vision loss in the elderly due to inflammation of the opthalmic artery
Investigations of GCA
Temporal artery biopsy within 2 wks of starting steroids
Treatment of GCA
High dose corticosteroids immediately
Add low dose aspirin
Pathophysiology of conjunctivitis
Inflammation of the conjunctiva
Non infectious causes of conjunctivitis
Mechanical, toxic, immune mediated and neoplastic
Presentation of conjunctivits
1) Dilated conjunctival vessels
2) Follicles - round collections of lymphocytes - nodules
3) Papillae - Cobblestone appearance of flattened nodules, red surface and pale base.
Bacterial causes of conjunctivitis
Staph/ strep pneu. h/flu, chlamydial
Viral causes of conjunctivitis
Adenovirus, HSV, HZV, Molluscum
Conjunctivitis treatment
Allergic - Prevent release of mediators and avoid triggers - mast cell stabilisers/ ati-histamines
Infective - Most are self limiting - good hygeine
Presentation of a corneal ulcer
Severe discomfort, red and watering eye, cant keep eye open
Red flags of corneal ulcer
Deep lid laceration, subconjunctival haemorrhage, pupil, iris or fundal abnormalities
Corneal ulcer treatment
Analgesia, remove abrasion and rust ring, photokeratitis, eye patch for 24 hrs
What is Uveitis
Inflammation of the uveal tract - pigmented layer that consists of the iris, ciliary body and choroid
Different forms of uveitis
Anterior - iris (most common)
Intermediate - vitreous and posterior ciliary body
Posterior choroid
Causes of uveitis
Inflammation, infection, infiltration 2’ to neoplasm, trauma, iatrogenic, idiopathic or ischaemic
Presentation of A I and P Uveitis
A - Unilateral pain, redness, blurred vision, headache
I - Painless floaters
P - Bilateral gradual visual loss, blurred vision, photophobia
Uveitis treatment
Trying to control inflammation, prevent visual loss and minimise complications
- Cycloplegic drugs to paralyse the ciliary body and relieve pain and adhesions
- Topical corticosteroids.
