Ophthal 3 Flashcards
Extraocular muscles functions:
- Med rectus
- Lat rectus
- Sup rectus
- Infer rectus
- Sup oblique
- Infer oblique
- Med rectus: adducts
- Lat rectus: abducts
- Sup rectus: elevates, adducts, int rotates
- Infer rectus: depresses, adducts, ext rotates
More powerful when in lateral
Recti arise from fibrous common tendinous ring - Sup oblique: depresses, abducts, int rotates
- Infer oblique: elevates, abducts, ext rotates
Also levator palpebral superioris
Via oculomotor, trochlear, abducens LR6SO4
Also optic nerve, and opthalmic division of trigeminal nerve supply structures in orbit
Opthalmic artery supplies orbit, giving off central artery which supplies retina. Opthalmic veins drain to cavernous venous sinus
Thyroid eye disease:
- Definition
- Risk factors
- Symptoms
- Investigations
- Management
- Complications
Thyroid eye disease:
- Definition: in graves disease where infiltrates extraoc muscles + tissues
- Risk factors: smoking, radioiodine
- Symptoms: No symptoms, Ocular irritation (dry/gritty/photophobia), Soft tissue involvement (corneal oedema/inj), Proptosis, Extraoc muscle involvement, Corneal exposure/ulceration, Sight loss
- Investigations: uss
- Management: lubricants, steroids, orbital decompression
- Complications: sight loss, globe subluxation, strabismus, exposure keratopathy, optic neuropathy
Diabetic retinopathy:
- Definition
- Risk factors
- Symptoms
- Grading
- Investigations
- Management
- Complications
Diabetic retinopathy:
- Definition: microvasc complication
- Risk factors: length, glucose control, obesity, htn, dyslipidaemia
- Symptoms: assymp, floaters, dec vision
- Grading
1. bg: cotton wool spots, hard exudates, microaneurysms, retinal haemorrhages
2. preprolif: venous bleeding, blot haemorrhages, intraretinal mirovascular abnormality
3. prolif: neovascularisation, vitreous haemorrhage
4. maculopathy: oedema, exudates - Investigations: oct, fluoroscein angiography gold standard
- Management: if bg annual monitor, if preprolif 4-6 monthly and maybe laser, if prolif then laser within 2 weeks + antivegf, if macula then anti vegf
- Complications: laser (reduces peripheral vision, dec qol night vision), vision loss, retinal/vitreous detachment, vitreous haemorrhage, cataracts
Central retinal artery occlusion:
- Definition
- Causes
- Symptoms
- Signs
- Investigations
- Management - immediate, definitive
- Complications
Central retinal artery occlusion:
- Definition: obstruction through central retinal art (branch of ophthalmic)
- Causes: atherosclerosis, gca
- Symptoms: sudden curtain coming down loss of vision painless
- Signs: rapd, fundoscopy pale retina with cherry red spot, carotid bruit
- Investigations: fluorosceine angiography
- Management - immediate, definitive
1. ocular massage
2. dec iop via: acetazolamide, timolol, iv mannitol, ant chamber paracentesis
3. dilate artery: carbogen, subling isosorbide dinitrate, oral pentoxifylline
definitive: thromboylsis or steroids - Complications: neovasc
Retinal vein occlusion:
- Definition
- Risk factors
- Symptoms
- Signs
- Management
Retinal vein occlusion:
- Definition: via thrombus and venous congestion can cause haemorrhages + macular oedema
- Risk factors: htn, smoking, high chol, diabetes, high viscosity (myeloprolif)
- Symptoms: painless loss vision
- Signs: dilated tortuous veins, cotton wool, hard exudates, flame + blot haemorrhages
- Management: conservative. unless if macular oedema then anti vegf, if neovasc laser photocoagulation
Retinal detachment:
- Definition
- Risk factors
- Symptoms
- Signs
- Investigations
- Management
Retinal detachment:
- Definition: neurosens photoreceptor layer of retina separates from rpe
- Risk factors: retinal tear, lattice degeneration, post vitreous detachment, trauma, diabetes, retinal malig, fx, cataracts surgery, myopia
- Symptoms: painless loss peripheral vision cobwebs, flashes + floaters
- Signs: dec acuity, rapd, loss reflex red
- Investigations: slit lamp within 24 hours
- Management : if tear laser, if detachment: vitrectomy, scleral bulking, pneumatic retinopexy
Optic neuritis:
- Definition
- Causes
- Symptoms
- Investigations
- Management
Optic neuritis:
- Definition: inflammation and demyelination of the optic nerve
- Causes: ms, sle, ra, isch optic neuropathy (gca, diab), infection syphilis, lymes
- Symptoms: severe retrobulbar eye pain worse with movement, changes to colour vision, flashes, dec contrast sensitivity, rapd, uhthoffs phenomenon
- Investigations: mri brain + orbits with gadolinium contrast
- Management: steroids iv, analgesia
Macular degeneration:
- Definition
- Function of macular + layers of macular
- Risk factors
- Dry AMD
- Wet AMD
- Symptoms
- Investigations
- Management
- Complications
Macular degeneration:
- Definition: degen of the macula
- Function of macular + layers of macular: choroid, bruchs mem, rpe, photoreceptors
- Risk factors: age, fx, caucasion, smoking, hyperopia
- Dry AMD: drusen
- Wet AMD: choroid neovascularisation
- Symptoms: progressive loss of central vision, metamorphsia
- Investigations: slit lamp/fundoscopy, oct gold standard, fluoroscein angiography
- Management: if dry then monitor self via amsler, vit ace. if wet anti vegf ranibizumab injection. can drive until 6/12
- Complications: charles bonnet
Retinitis pigmentosa:
- Definition
- Symptoms
- Signs
- Investigations
- Management
Retinitis pigmentosa:
- Definition: auto dom mut of rhodopsin gene degenerating photoreceptors rods in retina (needed for night + peripheral vision)
- Symptoms: night blindness, loss peripheral vision first, photopsia, glare
- Signs: bone spicules on periphery, waxy appearance + narrowing of arterioles
- Investigations: genetic testing
- Management: genetic counselling, vision aids, inform dvla
Retinoblastoma:
- Definition
- Symptoms
- Investigations
- Management
- Complications
Retinoblastoma:
- Definition: ocular malig auto dom rb1 in <18 months
- Symptoms: no red reflex, vision loss, bulging, strabismus
- Investigations: ophthalmic uss
- Management: enucleation
- Complication: retinal detachment, optic nerve invasion, hearing loss chemo
Vitreous haemorrhage:
- definition
- risk factors
- causes
- symptoms
- ix
Vitreous haemorrhage:
- definition: bleeding into vitreous humour
- risk factors: diab, trauma, anticoags, coag disorders, severe short sightedness
- causes: prolif diabetic retinipathy, post vitreous detachment, ocular trauma
- symptoms: painless vision loss, dark spots, red hue, floaters, dec acuity
- ix: fundoscopy, slit lamp, fluoroscein angiography, orbit ct
Posterior vitreous detachment:
- risk factors
- symptoms
- signs
- ix
- mx
Posterior vitreous detachment:
- risk factors: can lead to tears or retinal detachment, common in ageing + highly myopic people
- symptoms: sudden floaters + flashes, blurry vision cobwebbed
- signs: weiss ring
- ix: urgent 24 hour ophthalmogist
- mx: conservative will improve by 6 months, if assoc tear then needs laser
HTN retinopathy:
- definition
- classification
- mx
HTN retinopathy:
- definition: damage to small bv in retina due to chronic htn
- classification: keith wagener
1. mild narrowing arterioles
2. focal constriction bv + av nicking
3. cotton wool patches, exudates, haemorrhages
4. papiloedema
- mx: oct, fluoroscein angiography, same day referral if malig (blurry, visual field defect, headache, flushed face)
