Ophthalmology Flashcards
What is cataracts?
Opacification of the lens of the eye
What is the aetiology of cataracts?
Majority of cases are idiopathic age-related (senile cataracts). Numerous secondary causes including:
- Local: Previous eye trauma, uveitis, intraocular tumours
- Systemic: DM, metabolic disorders (hypocalcaemia, Wilsons disease), skin disease (atopic dermatitis, scleroderma), drugs (steroids), X-ray and UV radiation, myotonic dystrophy, genetic syndromes (Down’s)
- Congenital: Congenital rubella syndrome
What is the aetiology of cataracts?
Major cause of treatable blindness worldwise
What are the presenting symptoms of cataracts?
- Gradual onset painless loss of vision
- Glare from bright light, vision may worsen in bright light (especially with central lens opacity)
- May experience monocular diplopia and see haloes around lights
- May notice that they can read without glasses (nuclear sclerotic cataract may increase lens-converging power)
- In infants, may be amblyopia or nystagmus
What are the signs of cataracts on examination?
- Loss of reflex and hazy lens appearance
- Reduced visual acuity
What are the investigations for cataracts?
Unnecessary unless occurring at an early age or in background of systemic disease
What is conjunctivitis?
Inflammation of the lining of the eyelids and eyeball caused by bacteria, viruses, allergic or immunological reactions, mechanical irritation or medicines
What is the aetiology of conjunctivitis?
- Most common bacterial pathogens in infective include Pneumococcus, Staphylococcus aureus, M. catarrhalis and H. influenzae
- Viral: adenovirus, herpes simplex, Epstein-Barr, varicella zoster and enteroviruses
- Contact lens wear may lead to a keratoconjunctivitis
- Mechanical caused by chronic conjunctival irritation especially while sleeping.
What is the epidemiology of conjunctivitis?
Commonly affects males and females of all ages
What are the presenting symptoms of conjunctivitis?
- Watery discharge
- Itchy predominant symptom
- Eyelids stuck together
- Eyelids stuck together in mornings
What are the signs of conjunctivitis on examination?
- Ropy, mucoid discharge
- Prululent discharge
- Tender, pre-auricular lymphadenopathy
What are the risk factors for conjunctivitis?
- Exposure to infected person
- Infection in one eye
- Environmental irritants
- Allergen exposure
- Camps, swimming pools, military bases
- Asian or Mediterranean young male
- Atopy
- Contact lens use
- Ocular prosthesis
- Mechanical irritation
What are the investigations for conjunctivits?
- Rapid adenovirus immunoassay: 2 visual lines equal positive
- Cell culture
- Gram stain
- PCR
What is glaucoma?
Optic neuropathy with typical field defect usually associated with ocular hypertension (intraocular pressure more than 21mmHg)
What is the aetiology of glaucoma?
- Primary causes: Acute close angle glaucoma (ACAG), primary open-angled glaucoma (POAG), chronic closed-angle glaucoma
- Secondary causes: Trauma, uveitis, steroids, rubeosis iridis (diabetes, central retinal vein occlusion)
- Congenital: Buphthalmos, other inherited ocular disorders
What is the epidemiology of glaucoma?
- Prevalence 1% in over 40 years
- 10% over 80 yrs (POAG)
- 3rd most common cause of blindness worldwide
What are the presenting symptoms of glaucoma?
- ACAG: Painful red eye, vomiting, impaired vision, haloes around lights
- POAG: Usually asymptomatic, peripheral visual field loss may be noticed
- Congenital: Bupthalmos (ox eye), watering, cloudy cornea
What are the signs of glaucoma on examination?
By slit-lamp
- ACAG: Red eye, hazy cornea, loss of red reflex, fixed and dilated pupil, eye tender and hard on palpation, cupped optic disc, visual field defect (arcuate scotoma), moderately raised IOP
- POAG: Optic disc may be cupped. Usually no signs
What are the investigations for glaucoma?
- Goldman Applanation Tonometry: standard exam to measure ocular pressure
- Pachymetry: Detect pathologically cupped disc
- Gonioscopy: Assess to iridocorneal angle
- Perimetry (visual field testing): For arcuate scotoma (early), tunnel vision (late)
What is uveitis?
Inflammation of the iris and ciliary body (iritis or iridocyclitis)
What is the aetiology of uveitis?
- Anterior uveitis may be caused by infection (e.g. herpes simplex, herpes zoster)
- Can occur as manifestation of systemic inflammatory conditions e.g. juvenile chronic arthritis, HLA B27-related spondyloarthritides, sarcoidosis, Behcet’s disease
What is sympathetic ophthalmia?
Inflammation of the contralateral eye weeks/months after penetrating injury (rare)
What is the epidemiology of uveitis?
- Associated with sponduloarthritis
- 2x more common in males
What are the presenting symptoms of uveitis?
- Pain (ciliary spasm and inflammation, pain increases on accommodation)
- Photophobia
- Red eyes
- Blurred vision
- Lacrimation
- May rarely be associated with tubulointerstitial nephritis (flank pain, haematuria, proteinuria, sterile pyuria and acute renal failure)
What are the signs of uveitis on examination?
- Reduced visual acuity
- Ciliary flush (redness may be confined to the corneoscleral junction
- Hyponyon (proteinaceous exudate and inflammatory cells in the inferior angle of the anterior chamber)
- Small irregular due to posterior synechiae (adhesions of the iris to the lens)
What are the signs of uveitis with a slit lamp?
Keratic precipitates (deposits of leucocytes of the corneal endothelium)
What are the signs of uveitis with fundoscopy?
Excludes retinal detachment
Posterior inflammation or a tumour that may give rise to anterior uveitis
What are the signs of the complications of uveitis?
- Raised intraocular pressure
- Cataract
What are the investigations for uveitis?
Investigate for associated systemic conditions depending on associated symptoms:
- U&E’s
- Spondyloarthritides (sacroiliac joints X-ray, HLA typing)
- Sarcoidosis (CXR, serum calcium, serum ACE)
- Syphilis serology
