Eye disorders - the rest Flashcards
define ptergium
- Raised, yellowish wedge shaped growth of conjunctiva that extends onto cornea.
RF for ptergium
- Exposure to wind, dryness, dust ad sunshine (solar radiation).
- Hot climates
- Common In those that spend a lot of time outdoors - aka surfers eye or farmers eye
presentation of pterygium
- Painless – can cause dryness and irritation.
- Obstructs vision.
Diagnosis of ptergium
slit lamp exam
clinical
Mx of ptergium
- Corticosteroid drops and artificial tears
- Surgery – if vision impaired or for cosmetic reasons.
- Often comes back – prevented w/ sunglasses and artificial tear drops.
Define stabismus
aka squint
- Both eyes do not line up in same direction (misaligned).
Causes of squint
- Disorder of ext ocular muscles
- Abn in neuromuscular control of eye movement.
- Congenital (before 6 months) or acquired.
RF in developing squint
- Idiopathic
- Cerebral palsy, downs syn, hydrocephalus, space occupying lesion.
- Stroke – common cause in adults.
- Graves disease.
- Trauma – damage to oculomotor cortex or direct damage to eye muscles.
presentation of squint
diplopia in adults and amblyopia (dim/ blurry eyesight) in children.
- Paralytic squint = paralysis in one or more extra ocular muscles.
What are esotropia, exotropia, hypertropia and hypotropia?
- ESO = inwards
- EXO = outwards
- HYPO = downwards
- HYPER = upwards
Diagnosis of squint
- Fundoscopy (or red reflex) to rule out retinoblastoma, cataracts and other retinal pathology.
- Hirschberg’s test.
o
cover test
What is Hirschberg’s test for squint?
Observe where reflection of pen torch lies on cornea.
o Normal – reflection central bilaterally.
o Exotropia – reflection lies at inner margin of pupil.
o Esotropia – reflection lies on outer margin.
What is cover test for squint?
cover one eye and ask ptx to focus on object, this eye is observed for movement.
o This eye is then covered and other eye in uncovered and observed for movement.
o Esotropia – eyes move outwards (i.e the eye was turned inwards initially when covered). Opp for exotropia.
Mx of squint.
neonate - refer
- < 8 yrs w/ amblyopia and strabismus - eye patching (of good eye) ± cycloplegic drops, e.g atropine
- Glasses.
- Surgical alignment.
Define cataract
- Lens in eye becomes cloudy and opaque – reduces light entering eye – reduces visual acuity.
RF for cataract
- Increasing age – esp > 65yrs
- Smoking
- Alcohol
- Diabetes
- UV exposure
- Trauma
- Previous eye surgery
- Steroids
- hypoCa
- congenital cataract – are screened for using red reflex.
presentation of cataract
- painless
- difficulty reading/ watching TV/ recognising faces
- slow reduction in vision
- progressive blurring of vision
- color of vision changes – becomes more brown/ yellow
- starburst appear around light – esp at night.
- Paediatric cataract can present w/ squint
Dx of cataract
- loss of red reflex.
- lens appear grey/ white on slit lamp, also appears on flash photography.
Mx of cataract
surgery - pseudophakia
if symp are manageable - no Tx
Complications of cataract
hide pathologies, e.g macular degeneration , diabetic retinopathy
Endophthalmitis
- Posterior lens capsule opacification
- glaucoma
corneal and macular oedema.
Define age related macular degenration
- Degeneration of macula – causes progressive vision loss (most common cause of blindness).
- 2 types – wet and dry (wet has worse prognosis).
RF for age related macular degeneration.
- Aging
- Smoking
- White or Chinese
- FHx
- Male
- CVD + CVD risk factors
Presentation of age related macular degneration.
- Drusen
- Atrophy of retinal pigment ep.
- In wet AMD – release of VEGF stimulates production of new blood vessels – rapid vision loss (loss of vision over days and blindness over 2-3 yrs).
o Wet AMD usually bilateral. - Gradual worsening central visual field loss.
- Reduced visual acuity- worse on near vision. Poor vision at night.
- Photopsia
- Straight lines appear crooked or wavy.
- subretinal or intraretinal haemorrhages in wet ARMD.
Diagnosis of age related macular degeneration.
fundoscopy - drusen and scotoma.
snellen chart - reduced visual acuity
optial CT - gold tsnadard to Dx wet AMD
fluorescein angio - Dx of AMD
Mx of AMD
refer
dry - lifestyle changes to reduce progression
wet - anti-VEGF via injection to virteous chamber, x1/ month
Define retinal detachment
- Retina separated from choroid.
Pathophysiology of retinal detachment.
retinal tear - allows vitreous fluid to leak under retina and fill space between retina and choroid.
no blood supply to retina - ischaemia
RF for retinal detachment
- Diabetic retinopathy
- Eye trauma (rhegmatogenous retinal detachment)
- Old age
- Retinal malignancy
- FHx
- posterior vitreous detachment – vitreous comes away from retina at back of eye – happens w/ age.
presentation of retinal detachment
- painless
- peripheral vision loss – sudden.
o Shadow coming across vision. - Blurred/ distorted vision.
- Flashes and floater.
Dx of retinal detachment
painless flashers and floaters – assessment to detect retinal tears or detachment.
Mx of retinal detachment
refer
laser/ cryotherapy - prevent detachment
reattach - Vitrectomy, scleral bulking, Pneumatic retinopexy
complications of retinal detachment
if progresses to macula - blind
Define CRAO
RETINAL ARTERY OCCLUSION
- Blockage in central retinal A.
Causes and RF for CRAO
atherosclerosis - CVD RF
Giant cell arteritis - >50yrs, F, PMR
Presentation of CRAO
- sudden painless loss of vision
- Relative afferent pupillary defect
Dx of CRAO
- Fundoscopy – pale retina and cherry red spot.
check for carotid bruits, HTN, DM, AF
Mx of CRAO
Refer
test older people of giant cell arteritis - steroids
attempt to dislodge thrombus (only if present quickly after symp) - via massage, remove fluid from ant chamber, sublingual nitrates
longterm - conservative and 2* CVD prevention
Define CRVO
- Thrombus in retinal veins – blocking drainage of blood from retina.
Pathophysiology of CRVO
- blocked vein - retinal haemorrhage and macular oedema.
- VEGF - neovascularisation
Pathophysiology of CRVO
- blocked vein - retinal haemorrhage and macular oedema.
- VEGF - neovascularisation
Presentation of CRVO
Sudden painless loss of vision
Diff between CRVO and CRAO presentation
both sudden loss of vision, and painless.
renal A occlusion causes quicker vision loss
RF for CRVO
CVD risk factors
glaucoma
systemic inflammatory diseases
Dx of CRVO
fundoscopy - flame, blot hamorrhage, optic disc and macula oedma
check for leukaemia, inflammation, HTN, DM
Mx of CRVO
Refer
o Laser photocoagulation
o Intravitreal steroids (e.g. a dexamethasone intravitreal implant)
o Anti-VEGF therapies (e.g. ranibizumab, aflibercept or bevacizumab)
define optic atrophy
aka optic neuropathy
- Death of retinal ganglion cells (nerve fibres) that make up optic nerve.
RF for optic atrophy
- Increase ocular pressure (glaucoma).
- Ischaemia
- Compression (tumour).
- Inflammation – optic neuritis, giant cell arteritis in older people.
- Infection – in children presents as flu like history or post vaccinal optic neuritis, syphilis.
- Drugs that are toxic to optic N = ethambutol, amiodarone, alcohol, methotrexate and ciclosporin.
- Diabetes
presentation of optic atrophy
rapid vision loss (if gradual = hereditary).
symp vary according to optic N damage - from impaired colour vision to loss of vision
disc damage - painful
How is presentation of optic atrophy diff in elderly and young people?
- Young – history of eye pain, paraesthesia, ataxia or weakness – suggests demyelination.
- Older – transient vision loss, diplopia, temporal pain, fatigue, weight loss and myalgia – suggests ischemic optic neuritis due to giant cell arteritis.
Dx of optic atrophy
fundoscopy - pale, disc cupping if glaucoma
- visual function tests - red colour desaturation is early sign
neuoimaging - compression, demyelination
if unexplained - full workup - bruits,genetic abn, DM, MRI brain
Mx of optic atophy
remove cause, e.g pit tumour
Tx cause
lifestyle and drug modifications - reduce progression
define diabetic retinopathy
- Blood vessels supplying retina damaged by prolonged exposure to high sugar – causes progressive deterioration of retina.
Pathophysiology of diabetic neuropathy.
hyperglycaemia -> blot haemorrhages and hard exudates
microaneurysm and venous beading
cotton wool spots
growth factors - neovascularisation
what are the 2 types of diabetic retinopathy? and how do they present?
non proliferative (NDPR) and proliferative (PDR).
NDPR:
- Mild – microaneurysm
- Moderate: microaneurysms, blot haemorrhages, hard exudates, cotton wool spots and venous beading
- Severe: blot haemorrhages plus microaneurysms in 4 quadrants, venous beading in 2 quadrates, intraretinal microvascular abnormality (IMRA) in any quadrant
PDR
* Neovascularisation in retina or optic disc.
* Vitreous haemorrhage (blood in vitreous cavity).
Dx of diabetic retinopathy
fundoscopy
o Mild disease – microaneurysms, hard exudates, blot haemorrhages.
o Severe disease and signif ischemia - tortuous veins, cotton wool spots, large blot haemorrhages
Mx of diabetic neuropathy.
- Laser photocoagulation
- anti-VEGF meds
- Vitreoretinal surgery of severe
urgent 2 wk wait in opthal
PDR, macular involvement, retinal detachment, virtuous haemorrhage, CRAO, CRVO
pathophysiology of hypertensive retinopathy.
silver/ copper wiring - increase reflection of light
arteriovenous nipping
cotton wool spots
hard exudates
retinal haemorrhage
papilloedema
Dx of HTN retinopathy
fundoscopy
classification:
o Stage 1: Mild narrowing of the arterioles
o Stage 2: Focal constriction of blood vessels and AV nicking
o Stage 3: Cotton-wool patches, exudates and haemorrhages
o Stage 4: Papilloedema
Mx of HTN retinopathy
risk factors
HTN meds
Define glaucoma.
optic nerve damage due to rise in intraocular pressure
define open angle glaucoma and RF?
increase in resistance through trabecular meshwork – therefore aq humour cannot flow through meshwork and exit eye – so pressure increases slowly.
o SLOW, CHRONIC ONSET.
RF:
- Raised IOP
- HTN
- DM
- Corticosteroids
- Myopia (near-sightedness).
- Afro-Caribbean
- Genetics
define ACUTE angle glaucoma and RF?
iris bulges forward – seals off trabecular meshwork – prevents aq humour from draining – cont build-up of pressure.
RF:
- Female
- Chines and East Asia (rare in black).
- Shallow ant chamber
- Adrenergic meds – NA
- Anticholinergic meds – oxybutynin, solifenacin
- Tricyclid anti-dep – amitriptyline.
- Long sighted
Diff in presentation of open and acute angle glaucoma?
open angle:
- Rise in IOP asymp for long period.
- Diagnosed by routine screening.
- Gradual onset of fluctuating pain.
- Central scotoma in advanced disease.
acute angle:
- Severely painful red eye.
- N+/- V
- Hazy cornea
- Fixed, dilated affected pupil.
- Reduced visual acuity.
- Firm eyeball on palpation.
Diff in Dx of open and acute angle glaucoma?
open:
- Goldmann applanation tonometry
- fundoscopy - disc cupping, bonneting, pale optic disc
- visual field tests
acute angle:
- slit lamp
- gonioscope
Diff in Mx of open and acute angle glaucoma?
open:
- Tx if IOP ≥24 mmHg and risk of vision disturbance
- 1st line = trabeculoplasty
- 2nd = meds (1st latanoprost, 2. timolol, 3rd carbonic anhydrase inhibitor).
acute:
- admit and until then pilocarpine every 15 mins, o Acetazolamide 500mg oral, Analgesia and anti-emetic
definitive Mx - laser iridotomy
Pathophysiology of retinoblastoma.
inherited.
Rb1 on ch. 13 (recessive)
how does retinoblastoma present?
onset 3rd motnh preg to 5 yrs
leukocoria
strabismus
pain, buphthalmos
- Metastases to CNS, bones, bone marrow and liver.
Mx of retinoblastoma
– urgent referral.
radiotherpay/ chemo
DEARISM Arc (welders) eye
aka SNOWBLINDESS/ PHOTOKERATITIS
DEFINITION
- Sunburn of cornea and conjunctiva by ultraviolet (UV) light – causing sup keratitis.
RISK FACTORS
- climbers/skiers, welders, and sunbed users who have not used protective goggles
PRESENTATION
- After a delay of 6 to 12 hours following exposure to arc welding, sun lamps or other sources of UV light, the eyes become red, painful, watery and unduly sensitive to light.
- Blepharospasm
DIAGNOSIS/Ix
- fluorescein staining which may reveal multiple punctate corneal lesions.
MANAGEMENT
- Resolves in 24 hrs.
- Discharge with an eye pad, oral analgesia, and advice not to drive until recovered.
curtain coming down?
AMAUROSIS FUGAX
complete recovery after sec-mins
cause - embolis in retinal, ophthalmic, or ciliary artery orginate from carotid plaque
urgent referal
presentation of thyroid eye disease
aka graves
lid retraction
exopthalamos
lid lag
diplopia
What condition cause following:
a) starbusts around lights
b) halos around eye
c) crooked/ wavy appearance of straight lines
a) catarct
b) glaucoma
c) AMD
presentation and Tx of temporal giant cell arteritis
- Rapid and profound visual loss may be preceded by headaches, jaw claudication, general malaise, and muscular pains.
temporal A tender to palpate
pale papillodema, pale disc , high ESR
Tx - hydrocortisone
