Ophthalmology Flashcards
Define glaucoma
Progressive optic neuropathy characterised by typical optic disc changes and typical visual field defects, usually due to increased intraoccular pressure >21mmHg.
Summarise the aetiology of glaucoma
Primary glaucoma:
Open angle glaucoma
Closed angle glaucoma - acute and chronic
Secondary glaucoma: Trauma Uveitis Steroids Rubeosis iridis (new abnormal blood vessels on the iris formed by neovascularisation) - due to diabetes or central retinal vein occlusion
Congenital: Bupthalmos (enlargement of the eye balls)
What are the risk factors of glaucoma?
Closed angle: Female sex Hyperopia (long-sighted) Family history Asian ethnicity Advanced age
Open angle: Afro-Caribbean ethnicity Increased intraoccular pressure Age >50 Hypertension Diabetes Mellitus Myopia ‘short sighted’
Summarise the epidemiology of glaucoma
Glaucoma is the 2nd leading cause of blindness in the world
Primary open angle is the most common type of glaucoma
45 million people worldwide
One third due to primary angle closure glaucoma
Angle closure glaucoma more common in Asians
Angle closure glaucoma more common in women
Acute angle closure most common between 55 and 65 years old
What are the presenting symptoms of glaucoma?
Open angle:
Often asymptomatic
Peripheral visual field loss which can then progress to central loss
Closed angle: Abrupt onset of symptoms Painful eye Red eye Blurry vision Headaches Nausea Visual halos Aching eye or brow pain
Congenital:
Bupthalmos
Watering
Cloudy cornea
What are the signs on physical examination of glaucoma?
Closed angle: Red eye Hazy cornea Loss of red reflex Fixed and dilated pupil Eye is tender and hard on palpation Cupped optic disc Visual field defect Raised intra-ocular pressure
Open angle:
Optic disc may be cupped
Usually NO signs
What are the appropriate investigations for glaucoma?
Visual fields testing:
Arcuate scotoma - partial loss of vision in otherwise normal field
Peripheral field loss (tunnel vision) as late stage
Fundoscopy/Optic nerve imaging - cupping of optic nerve
Goldman Applanation Tonometry - raised intra-ocular pressure >21mmHg. (Normal = 15mmHg)
Pachymetry - USS or optical scanning to measure corneal thickness - thin cornea (<590mm)
Gonioscopy - Assess iridocorneal angle - low in closed angle glaucoma
Define conjunctivitis
Inflammation of the lining of the eyelid and eyeball caused by most often viruses, but also bacteria, allergy, immunologic reactions, mechanical irritation or medicines
Summarise the aetiology of conjunctivitis
Most often viral: Most common cause is ADENOVIRUS EBV HSV VZV
Bacterial: Pneumococcus Staphylococcus aureus Chalmydia - causes chronic conjunctivitis Neisseria
Allergy
Mechanical irritation eg cataract use - excessive use, poor hygiene
Summarise the epidemiology of conjunctivitis
Affects all ages
Bacterial conjunctivitis is more common in children
Viral conjunctivitis is more common in adults
What are the presenting symptoms of conjunctivitis?
Red eye
Thin, watery discharge in viral and allergic
Thick, purulent discharge in bacterial
Itchy eye in allergic, burning sensation in viral
Unilateral involvement if viral, bilateral involvement if bacterial
Usually vision is unaffected
Photophobia if corneal involvement
What are the signs on physical examination of conjunctivitis?
Conjunctival injection (blood shot eye) Dilated conjunctival vessels Chemosis Tarsal conjunctival follicles in viral Conjunctival papillae
What are the appropriate investigations of conjunctivitis?
Mostly a clinical diagnosis
Can do rapid adenovirus immunoassay
Define cataracts
Opacification of the lens of the eye leading to a decreased visual acuity
Summarise the aetiology of cataracts
Idiopathic (part of ageing process) - MOST COMMON
Metabolic disorders - diabetes, Wilson’s
Inherited/congenital problems - congenital rubella syndrome
Trauma
Medications eg steroids
Infection - rubella
Scleroderma
Risk factors: Smoking UV exposure Age > 65 Diabetes mellitus Eye Trauma Long-term corticosteroid use Family history of congenital cataracts Uveitis
Summarise the epidemiology of cataracts
The MOST COMMON cause of treatable blindness worldwide
Age-related cataracts: most common cause
What are the presenting symptoms of cataracts?
Gradual-onset PAINLESS vision loss Decreased visual acuity Glare from bright light May find it harder to see in bright light Difficulty seeing at night Blurred vision Increased falls See halos around light Faded colours/washed out colour vision Usually BILATERAL
What are the signs on physical examination of cataracts?
Loss of red reflex
Hazy lens appearance - opacity of lens
Decreased visual acuity not corrected by refractive correction
What are the appropriate investigations for cataracts?
Dilated fundus exam - normal fundus and optic nerve
Measure intraocular pressure - normal or elevated if glaucoma
Glare vision test
Slit lamp examination of anterior chamber - cataract visible
Pupillary reflex - loss of red reflex
Define uveitis
Inflammation of the iris and cililary body
Summarise the aetiology of uveitis
Bacteria: TB, syphillis Viruses: CMV, HSV Fungal: candidiasis Parastic: toxoplasmosis Non-infectious: rhuematoid arthritis, ankylosing spondylitis, Crohn's, sarcoidosis Trauma
Anterior uveitis: mostly idiopathic or HLA-B27 associated autoimmune causes
Posterior uveitis: mostly caused by local or systemic infection or inflammation
Risk factors: Inflammatory diseases of the joints Bowel or skin HLA-B27 positive Ocular trauma Age 30-40
Summarise the epidemiology of uveitis
Peak age of presentation 30-40 years old
Anterior uveitis more common
Uveitis associated with spondyloarthropathy is twice as common in males
What are the presenting symptoms of uveitis?
Anterior uveitis: Painful eye Red conjunctiva without discharge Decreased vision Photophobia Hypopyon - accumulation of pus in anterior chamber Flare
Posterior uveitis:
Painless decrease in visual acuity
Floaters
What are the signs on physical examination of uveitis?
Constricted or non-reactive pupil Retinal exudates and oedema Optic nerve oedema Optic disc swelling Retinal haemorrhages Reduced visual acuity Hypopyon (exudate and inflammatory cells in the inferior angle of the anterior chamber)
What are the appropriate investigations for uveitis?
FBC - high WCC if due to infection
ESR/CRP - elevated if due to infection
Investigations for associated systemic conditions:
Spondylarthritis - sacroiliac joint X-ray, HLA-typing
Anti-nuclear antibodies, HLA-B27
Slit-lamp examination:
Flame haemorrhage in anterior uveitis, leukocytes present in anterior chamber
