Ophthalmology Flashcards
Describe the classic features of cataracts
Symptoms occur gradually over long period of time:
- Myopia (short-sightedness)
- Blurry vision -> visual loss
- Dazzling in sunshine/bright lights
Describe the causes/risk factors for cataracts
- Older age
- DM
- Steroids
- Congenital causes: rubella, Wilson’s
Describe the management of cataracts
Conservative:
- Glasses
- Mydriatic eyedrops
Surgical: if significant impact on life/driving
Describe the types of ophthalmologic investigations and their uses
- Visual acuity: Snellen chart
- Fundoscopy: visualise the retina eg. Dx/Ix papilloedema, retinopathy, retinal A/V occlusion
- Slit-lamp: Dx macular degeneration, retinal detachment, cataracts, corneal injury
- Tonometry: measures pressures in the eye eg. Dx glaucoma
Describe some conditions of the outer eye
- Stye/hordeolum: acute, tender, red swelling. Occurs in eyelash follicle.
- Chalazion: abscess of Meibomian glands. Not located on eyelash line. Deeper + larger.
- Blepharitis: swelling of the eyelid + conjunctival injection.
- Peri-orbital cellulitis: swelling of area surrounding eye without eye involvement
- Orbital cellulitis: swelling of deeper orbit w eye signs
List some causes of a red eye
Lid: chalazion, blepharitis, cellulitis
Conjunctiva: conjunctivitis, subconjunctival haemorrhage
Sclera: scleritis and episcleritis
Cornea: corneal abrasion, keratitis
Anterior chamber: uveitis, iritis, acute glaucoma
Describe some conditions affecting the conjunctiva
Conjunctivitis: bacterial, viral, allergic
Subconjunctival haemorrhage
Describe the classic presentation of conjunctivitis and relevant negative findings
Unilateral/bilateral eye discomfort, discharge, redness
- Sticky/purulent: bacterial eg. Staph, Strep, Haemophilus
- Watery: viral
NO change in acuity or pupil response, NO ciliary flush
Describe the management of conjunctivitis
Conservative:
-Hygiene
Medical:
- Bacterial: chloramphenicol eyedrops
- Allergic: antihistamines (PO or drops)
Describe some conditions affecting the sclera
Episcleritis: acute red eye without pain. Idiopathic, gout. Resolves spontaneously, can use topical NSAIDs
Scleritis: acute red eye VERY painful. Scleral oedema. Assoc with autoimmune disease. Needs systemic management eg steroids + NSAIDs
Describe some conditions affecting the cornea. How are they identified?
- Corneal abrasion: epithelial breach caused by trauma. Causes pain, photophobia, blurry vision. Give chloramphenical drops for prophylaxis.
- Corneal ulcer eg. HSV. Topical/PO aciclovir
- Keratitis: inflammation of cornea. Causes pain, photophobia, conjunctival injection + ciliary flush.
Slit-lamp with fluoroscein stain shows defects
What is the uvea?
Part of the eye including iris, ciliary body and choroid
Describe the presentation of uveitis/iritis
Acutely red eye: ciliary flush -Pain -Photophobia -Blurry vision -Pain on convergence (Talbot's test) \+ may be assoc with systemic diseases eg. IBD, RA
Describe the management of uveitis/iritis
Refer to ophthal
- Steroid eyedrops
- Cyclopentolate drops
Name the types of glaucoma and describe the pathophysiology
Two main types:
- Acute closed angle glaucoma: blocked flow of aqueous humour thru canal of Schlemm -> ^^ pressure
- Chronic open angle glaucoma: defect in trabecular meshwork gradually -> ^ pressures over time
Describe the presentation of glaucoma
Acute:
-Prodrome: rainbow halo around lights at night
-Severe pain +/- N+V
-Blurry vision, red eye
O/E: cloudy cornea, ciliary flush, irregular fixed pupil, ‘hard eye’. IOP >40
-Assoc with female,
Chronic:
- Peripheral visual field defect (1st is superior nasal field)
- Slowly progressive
- IOP >21
- Assoc with DM, Afro-Caribbean, FHx, steroids, HTN
Describe the management of glaucoma
Acute:
- Refer to ophthal
- Pilocarpine drops (miosis to open blockage)
- Topical beta-blocker (decrease aqueous formation)
- Acetazolamide IV (decrease aqueous)
- > surgical Mx
Chronic:
- Topical beta-blockers (timolol)
- Prostaglandin analogues (latanoprost)
- Alpha agonists
- Acetazolamide
- Surgical: trabeculoplasty
Describe some causes of visual loss
Chronic:
- Worldwide: trachoma (chlamydia)
- Glaucoma
- Cataracts
- DM retinopathy
- Age-related macular degeneration
Sudden:
- Inflammation: optic neuritis, GCA
- Vascular: TIA, retinal artery or vein occlusion, vitreous haemorrhage
- Retinal detachment
- Acute glaucoma
Describe the presentation of age-related macular degeneration
Slowly progressive central visual loss
Describe the presentation of retinal detachment and the cause
Sudden onset painless visual loss Remember the 4 Fs: -Floaters: acute onset, many -Flashes -Field loss -Fall in acuity
Separation of retinal layers. RFs: DM, surgery, trauma
Describe the management of retinal detachment
Refer to ophthal for urgent surgery
Describe the presentation of central retinal artery occlusion
Sudden onset unilateral visual loss
- Afferent pupillary defect
- Pale retina with cherry red macula
Describe the presentation of retinal vein occlusion
Sudden onset unilateral visual loss
- RAPD
- ‘Stormy sunset appearance’ on fundoscopy
Describe the causes and presentation of vitreous haemorrhage
Causes: trauma, surgery, DM (new vessels)
Small bleeds -> small black dots in vision, floaters
Large bleeds -> visual loss, loss of red reflex
Describe the presentation of optic neuritis
Acute loss of visual acuity and colour vision
- Pain
- Enlarged blind spot
- Afferent defect
- Optic disc swollen, blurred
Describe some important questions to ask patients with visual loss
Headache: GCA
Floaters/flashing lights: detachment
Pain with eye movements: optic neuritis
Describe some red flags for eye conditions that warrant referral and conditions they may indicate
- Change in acuity: may things
- Painful loss of vision: glaucoma, optic neuritis,
- Abnormal pupils: optic neuritis, retinal artery/vein occlusion, glaucoma, uveitis
- Photophobia: uveitis, keratitis
What is strabismus? Describe the types
Aka Squint
Non-paralytic:
-Esotropia vs exotropia: eye points in or outward
Paralytic: due ot CN palsies, usually have diplopia
III: down and out pupil (+ ptosis, mydriasis)
IV: vertical diplopia
VI: horizontal diplopia
Describe some basic tests for non-paralytic squint
Pupillary reflection: shine light directed at patient, should reflect at same point in both pupils. asymmetry = squint
Cover test: focus on one point. Cover each eye in turn. Covering good eye will cause squint eye to move to focus
