Ophthalomology Questions Flashcards
List 6 reasons for decreased vision in diabetes
Diabetic Refractive Errors
Cataracts
Diabetic Retinopathies (including background retinopathy, maculopathy, proliferative retinopathy)
Vitreous Haemorrhage (due to weak abnormal blood vessels)
Glaucoma
Retinal detatchment (secondary to vitreous scarring)
List three types of retinopathies in diabetes
- Background retinopathy
- Diabetic Maculopathy
- Proliferative/pre proliferative
What is retinal detachment ?
Retinal detachment occurs when there is retina peels off the inside of the eye, usually due to holes/tearing. Fluid from the vitreous enters the hole and dissects it more and more.
What are the symptoms of retinal detachment ?
flashes (pulling on retina) and floaters (blood or pigment) and shadow/curtain over eye (detachment)
What are eye pathologies in diabetes?
Microaneurysm formations
Haemorrhages
Hard exudates (white/yellow) globules of fat from leakage of vessels
Retinal oedema from transudation from disruption of tight junctions in vessels
Leakage due to disruptions in pericytes and disruption of tight junctions
Vessel and capillary closure = ischaemia
Neovascularisaiton of vessels
Causes of Cataracts
Ageing (commonest)
Diabetes
Trauma and intra-ocular bodies
Ionizing radiation (UV light and X ray)
Steroid and phenothiazine (antipsychotic ) Medications
Metabolic disorders (galactose metabolism disorder)
COngenital (Downs syndrome, Myotonic Dystrophy, Rubella)
Retinal Detachment Clinical presentation
Flashes, floaters and blurred vision (curtain/shade)
What is retinal detachment caused by ?
Risk factors include: Trauma Diabetes Central Vein Occlusion Disease of Prematurity Myopia Vitreous Scarring and contraction
What is the criteria for vision that has to be met in order to drive on the road?
6/12 with both eyes open and 140 degrees of visual field with both eyes open
What investigation is contraindicated in the presence of intraocular foreign body?
MRI (due to metal shards, which in an MRI turn into a washing machine)
What is anterior uveitis ?
Inflammation of the uvea (iris, ciliary body and choroid)
What are the three layers to the eye and what do they each contain ?
- Sclera and cornea
- Uvea: contains iris, ciliary body and choroid
- Retina
what are the three chambers of the eye?
Anterior (volume between cornea and iris) contains aqeuous humour
Posterior (between iris and lens) contains aqeous humour and maintains IOC
Vitreous chamber between lens and retina
What % of IOFB are due to hammer? what do you need to use for this ?
80% Need to Xray the globe
What are the features of acute anterior uveitis?
Acute onset painful (dull ache) photophobia, secondary watering and redness
What three diseases is anterior uveitis associated with?
Autoimmune disorders such as Rhuematoid, Ankylosing spondylitis, Crohns
Intermediate uveitis: what is this inflammation of? What are symptoms?
Inflammatory signs in the vitreous :
PAINLESS blurred vision and vitreous floaters with snowbank appearance
Intermediate uveitis: What disease is this associate with ?
sarcoidosis
Posterior uveitis: What is this inflammation or and what si the signs?
choroid/retina
painless blurred vision + vitreous floates
What two diseases is posterior uveitis assocated with ?
INfections + bechet disease
becet disease
Blood vessel inflammation throughout the body: causes blood vessel inflammation throughout your body. The disease can lead to numerous signs and symptoms that can seem unrelated at first. They can include mouth sores, eye inflammation, skin rashes
What is the condition called when the eye loses its ability to focus on near objects from age 40 and above?
Presbyopia
What is the commonest malignancy seen in the eyelid?
BCC
What investigation is contraindicated in the presence of intraocular foreign body?
MRI
Why is myopia risk factor for retinal detachment ?
Myopia have longer eyes (axial elongation), which means that the retina is more stretched and therefore prone to peripheral retinal tears.
Myopia
Nearsightedness, the ability to see close objects more clearly than distant objects.
“need medical doctors” for healthy children
What is the usual prescribed optic diopter (D) for the above condition at the age 45?
+0.75D
What is the condition called when the eye loses its ability to focus on near objects from aged 40 and above?
presbyopia
Temporal arteritis:
What are the symptoms?
transient visual loss which then becomes permanent (ischaemic then occlusion) temporal headache, jaw and tongue claudication
What is temporal arteritis?
Opthalmic emergency:
Vasculitis of medium and larged sized arteries (superficial temporal, posterior ciliary and opthalmic arteries
what condition is temporal arteritisi associated with ?
POlymyalgia Rhuematica
What are the diagnostic tests ?
ESR/CRP and temporal artert biopsy(only +ve in 50%) + clinical suspcition
treatment for temporal arteritisi?
high dose prednisone 60mg OD (taper as symptoms resolve - treatment duration at least one year)
what is glaucoma? 3 associated things
optic nerve atrophy with raised intraocular pressure
- raised IOC pressure
- Visual field loss
- Optic nerve atrophy
Normal cup to disc ratio
0.6 or less:
CUp = cavity in optic disc which is optic nerve head.
Cup contains nothing but surrounded by axons of the optic nerve.
Larger cup means less axons.
Glaucoma is associated with cup/disc ratio of 0.7 or more = cupping sign
Referral guidelines for glaucoma:
Family history
suspicious optic disc
IOP > 21mmHG on 2 occasions.
IOP > 26mmHG on one occasion
COAG ( Chronic open angle Glaucoma)
Open angle means the trabecular meshwork through the optic disc becomes clogged drainage is clogged, which increased IOP, which leaves wide open angle between the iris and cornea = symptoms and damage not noticeable
COAG clinical presentaiton
gradual vision loss (need screening)
COAG diagnosis
visual field test (loss peripheral vision)
Tonometry measurment of IOP
Fundoscopy (cupping of optic disc above 0.7
COAG treatment
Topical B Blocker (decreases aqeous humour production - block sympathetic nerve in ciliary body) Topical Pilocarpine (parasympathetic to increased outflow and reduce muscles) Oral Acetazolamide (carbonic anhydrase inhibitor dec fluid)
COAG: What is the clinical signs? What are risk factors?
Clinical Signs: Gradual loss of peripheral vision
Diabetes and Myopia
COAG: Diagnosing 3 things
Visual field test (loss of peripheral vision) Tonometry (measurement of IOP)
Fundoscopy (cupping of optic disk)
COAG pathophysiology?
Disease trabecular meshwork leads to poor draining, build up of fluid and therefore increased IOP
Closed angle glaucoma pathophysiology
Decreased flow of aqueous humour in the anterior chamber ( between iris and cornea) ldue to the iris being pressed against cornea, leading to build up pressure in posterior chamber ( between iris and lens) leading to angle closure that increases IOP
What are risk factors for closed angle glaucoma
asian ethnicity and prolonged pupillary dilatation (anticholinergic dugs - e.g. atropine and some anti-depressants
Clinical symptoms for closed angle glaucoma
sudden onset eye pain and blurred vision
associated headache nausea and vomiting
diagnosis for closed angle glaucoma
clinical + fixed pupil and hard red eye
What is treatment for closed angle glaucoma?
Topical β-blocker ( aqueous humour production) Topical pilocarpine ( aqueous humour outflow) IV acetazolamide (carbonic anhydrase inhibitor)
Laser peripheral iridotomy (definitive)
Age related macular degeneration :
Atrophic Dry type
Clinical Atrophic presentation
gradual painless loss of central vision
Atrophic Dry macular degeneration fundoscopy
drusen (accumulation of yellow deposits)
pigmentary changes
pain of the red eye that is resolved with topical anaesthetics is due to ?
superficial disease (e.g. corneal or conjunctival rather than glaucoma or uveitis)
Two features of the acute red eye that prompt immediate referral to opthamalogist
Marked pain
reduced visual acuity
ACUTE RED EYE:
4 main types
Trauma
Infections (conjunctivitis, contact lens keratitis)
Inflammation (anterior uveitis)
Glaucoma
What do you NOT use for acute red eye
topical steroid
What should you not prescribe for local pain reflief acute red eye?
never prescribe local anaesthetics for pain relief
if there is possibility of the foreign body: What exam MUST you do
evert the eyelid - PR of ophthmalogy
treatment for atrophic macular degeneration?
No treatment Can give vitamins which will SLOW it down, however cannot treat this
Exudative wet macular degeneration: Clinical presentation
Rapid painless loss of central vision
What is seen on fundoscopy for exudative (wet) age related macular degeneration ?
Haemorrhage and subretinal fluid (due to growth of abnormal blood vessels in the choroid that lead to leakage)
what is treatment for exudative wet age related macular degeneration ?
VEGF inhibitors (avastin)
Phototherapy (Photodynamic therapy is a form of
laser treatment. It uses a lightsensitive chemical to destroy the
abnormal blood vessels under the
macula)
iritis is the same as ?
anterior uveitis
Viral vs bacterial conjuncitivitis
Viral: Self limiting, very contagious, no discharge (watery)
Bacterial: Bilateral thick discharge needs treatment of cholamphenicol drops
Ptsosis 3 causes
Above tentorium = drugs of any kind
Third Nerve Causes: any causes aneurysm/brain tumour etc
Neuromuscular Junction : Myasthenia Gravis
Muscle disorders: Muscular Dystrophy/Multiple Sclerosis
Senile Ptosis (Levator dehiscence ptosis, the tendon of the muscle that lifts the eyelid (the levator palpebrae) may loosen or detach from its point of insertion.)
Heavy lid (stye/oedema)
Horners Syndrome (acute neck trauma to carotid body or chronic pancoast tumour )
2 Principles of management for penetrating eye injury
eye is sutured closed + explored under general anaesthetic
anti-emtics for pain relief as vomiting is BAD + evert eyelid
Which patient group is bacterial conjunctivitis very BAD for ?
neonates can get organisms from the birth canal (herpes, chlamydia, gonococcus).
These require urgent referral and must be seen by an ophthalmologist that day
(the eye may perforate in 24 hours…).
treatment for amblyopia
occlusion therapy (covering of one eye and forcing "bad" eye to work harder) glasses (to fix esotropic strabmismus - from accomadation error)
what is two important mechanisms that are important in amblyopia treatment
Treatment before 8 years = IMPORTANT
important to trial at any age however as risk of permanent visual loss
what is ambylopia
neurodevelopmental disorder with unilateral (less commonly bilateral) reduction in visual acuity - not structural cannot be treated by glasses alone.
Complications of Cataract surgery
Detachment of the retina
Haemorrhage
Damage to or dislocation of the IOL
Rarely, inflammation of the unoperated eye, which is called sympathetic ophthalmia
