24 - visual disturbance and impairment / 26 - red eye Flashcards
Muscles of eye and movements?
Superior rectus: up
Lateral rectus: out
Medial rectus: in
Inferior rectus: down
Superior oblique: internal rotation
Inferior oblique: external rotation
Cranial nerve innervation of eye muscles
3rd Oculomotor: everything else.
4th Trochlear: Superior oblique
6th Abducens: lateral rectus (ABDUCTS
Most common cause of strabismus?
Ix?
Cure/
Idiopathic is most common, can be secondary to loss of vision or neurological defects.
Detect with corneal reflections
Cure is surgical.
Other name for amblyopia?
What happens?
Lazy eye.
Decreased vision in an eye which otherwise appears normal, can occur because of strabismus.
Brain either does not receive visual signals or ‘switches them off’ to avoid diplopia.
Sx of amblyopia ? Mx?
Causes poor visual acuity and depth perception.
Treat with eyepatch or atropine.
What causes optic neuritis? Key association? sx?
Demyelination of optic nerve. Leads to visual loss. Usually unilateral.
Associated with MS.
Foggy vision and pain on movement of eye. Typically presents with loss of red vision.
What happens / sx in macular degeneration?
Blurred or absent vision in central field (macula).
Peripheral field unaffected.
Rfs of macular degeneration?
Risks: aging, hypertension, cholesterol disease, obesity and smoking.
Dry or wet.
Mx of macular degeneration?
Wet treatment with anti-VEGF medication (ranibizumab, Avastin) or LASER coag.
No treatment for dry.
What should you tell people who have macular degeneration
Charles-Bonnet syndrome and assured that it is not a feature of mental illness.
What is charles bonnet?
visual hallucinations in those who have lost sight
Sx of retinal detachment?
floaters, flashers. If both of these are present do fundoscopy for visual field loss and refer to ophthalmology
Rfs of retinal detachmnet?
Amblyopia, previous eye surgery, malignancy
Mx of retinal detachment
Surgical - vitrectomy
What form of conversion disorder can you get with eye?
What still happens?
hysterical visual loss
Tracking saccade still occurs.
Diagnosis of exclusion
What is pailloedema? cause?
Optic disc swelling caused by raised ICP.
Features of papilloedema
Loss of venous pulsation, enlarged blind spot.
What should you not do with papilloedema ?
LP
Mx of papilloedema ?
Many causes that -> raised ICP - Mx those
acetazolamide for IIH
Features of cranial nerve palsys oculomotor? trochlear? abducens? Damage to sympathetic trunk?
Oculomotor: down and out with ptosis and mydriasis
Trochlear: verticle double vision
Abducens: esotropion with associated diplopia.
Horner’s: damage to sympathetic trunk. Miosis, prosis, anhydrosis, ptosis.
Types of glaucoma?
Closed flow - blockage at iris
Open - further inside
Sx of glaucoma?
Painless red eye. Increased cup to disc ratio. Visual field loss. Optic nerve changes.
Mx of glaucoma
B blocker
topical prostamide
What is uveitis? Sx?
Inflammation of uvea.
Ophthalmic emergency
Redness, photophobia, pain, blurred vision,
Cause of uveitis?
infective
commonly associated with autoimmune cause
Mx of uveitis?
pred eye drops if non infective
infective - ask micro
Sx of conjunctivitis?
Mx?
When to seek help? WHat to do?
Pain, red eye, itchiness
Largely self-limiting, expect remission within 2 weeks.
OTC eyedrops.
If photophobia or decrease in visual acuity develop then seek help
Chloroamphenicol is Abx are required.
