Ophthalmology Flashcards
What are the causes of blepharitis
staph infection, meibomian gland dysfunction, seborrheic dermatitis
draw the visual defect diagram
(check online)
what is homonymous hemianopia
when the visual field defect is on the same side on each eye eg the left
what is heteronymous hemianopia
bitemporal/binasal- half a visual field is lost
what is the outer layer of the eye called
sclera
what structures influence the length of the lens
ciliary bodies, suspensory ligaments
what is the jelly like fluid infront of the pupil covered with?
cornea
what is the layer under the sclera
choroid
what is the innermost layer of the eye called
retina
what is the spot at the back of the eye called that is specialised for visual acuity
fovea
what photo receptor cells does the fovea contain? what are their function?
cones, colour vision
function and location of meibomian glands
oil production which prevents eyes from drying out– line the margin of the eye lids (where eyelashes are)
sx of blepharitis
gritty eyes burning sensation conjunctival redness ****loss of eyelashes recurrent lid lumps (chalazion, styes) *****worse in the morning
what other conditon may blepharitis be associated with? tx?
may be assoc with Rosacea (Skin condition with redness/flushing/telangiestasia/pustules on the face)- tx with metronidazole
Blepharitis Management
hygiene
1. warm massage of the eyelids
***tear substitutes
chloramphenicol ointment 1%
What is a chalazion
Meibomian Cyst, due to gland blockage
sx of chalazion
swelling on eyelid
PAINLESS
may start as a stye (painful)
often not quite on lashline and on upper eyelid
tx of chalazion
hot compress
gentle massage of the gland
safety net periorbital cellulitis- change in vision, very painful/uncomfortable, fever
if not resolved within 4w- refer
what is UL blepharitis a red flag for
tumour
sx of a stye
small lump on the lash line
angry, tender, red lump, uncomfortable
what is a stye
infection of a lash follicle- usually staph
What are the most common causative organsisms of Periorbital cellulitis
Staph aureus, H.influenzae type B- often follows URTI
sx of periorbital cellulitis
systemically unwell
often a child
fever
erythema, tenderness around the eyeball
tx periorbital cellulitis
5-7 day course of abx
adults- co-amox 500/125mg TDS for 1 week/clarithro 500mg BD for 1 week with metronidazole
children- fluclox 125mg QDS for 1 week/coamox
incision an ddrainage
referral to paeds, ENT, MDT
Complications of Periorbital cellulitis/red flags
ocular proptosis limited ocular movement decreased visual acuity loss of red/green colour vision- optic nerve is comprimised visual loss
what is conjunctivitis
inflammation of the conjuncitva- white part of the eye, covering the sclera), and inner layer of the eye
causes of conjuncitvitis
Viral- adeno (lymphadenopathy)
Allergy
Bacterial- Staph
Chemical
Sx of conjuncitvitis
generally BL red eye discharge- clear=viral, mucous=allergy, purulent- bacterial blurry vision due to discharge lids sticking together
Management of conjunctivitis
Viral- pt reassurance
Allergic- antihistammine eye drops/PO
Bacterial- Abx if severe />7days– Fusidic Acid 1% eye drops, Chloramphenicol 1% ointment
Bathing/cealning eyelids with cotton wool soaked in sterile salt water (boiled)
COOL compress
artificial tears
What is the difference between scleritis and episceritis
Scleritis
- inflammation of the full thickness of the sclera
- serious but rare
- commonly seen with other AI conditions
Episcleritis:
- inflammation of the thin vasular tissue later between conjunctiva and sclera- inflamamtory, AI
sx and tx of scleritis
- severe eye pain worse on eye movs
- red, blood shot eye in sclera
- **- photophobia
- eye watering
- polymyalgia rhuematica, RA, SLE, spndyloarthropathies, Granulomatosis, GCA
tx- refer urgently, NSAIDs, immunosupression
sx and tx of episcleritis
UL, no pain, may be a bit uncomfortable
Acute onset
localised redness eg half of the eye
tx
- very common
- reassure
- lubricating eyedrops
- if severe- topical corticosteroids/oral NSAIDs
if it’s very red and painful- redflag for scleritis
Anterior Uveitis- what is it
inflammation of the uvea- which concludes the iris anteriorly and the ciliary bodies, and choroid posteriolrly
Causes of anterior uveitis
seronegative arthritis eg ank spond, JIA; sarcoidosis
sx and signs on examination of anterior uveitis
UL acute onset intensely painful red eye reduced visual acuity photophobia ***irregular or small fixed pupil(s) with or without back pain (ank spond)
ciliary flush
may have pus in anterior chamber
what would you see on slit lamp in someone with anterior uveitis, what other things would you check?
fibrin clot in anterior chamber of cornea
kerratic precipitates
irregular pupils
check visual acuity and red reflex
management of stye
self-limiting NO NEED FOR ABX
WARM compress
if recurrent- punture and drain
ix and management of anterior uveitis?
fundoscopy slit lamp ocular pressure find the cause: bloods- autoantibodies- RF, anti-CCP, CRP, ESR, HLA-B27 - CXR (sarcoidosis)
- treat with eye dilation (cyclopentolate)
- prednisone drops
what is optic neuritis
inflammaiton of the optic nerve
causes of optic neuritis
demyelination- MS idiopathic hereditary- Leber's infectious- viral, toxoplasmosis, TB, Lyme, AIDS autoimmune- sarcoidosis, SLE tertiary syphillis
sx of optic neuritis
UL loss of vision over hours-days - ***central scotoma!!!!! - diplopia - pain (on moving eyes) - loss of/change in colour vision/haziness of vision photophobia sometimes - ***RAPD/marcus gunn- light in affected pupil only causes pupils to react mildly, and light to unaffected eye will cause normal constiction in both pupils - papilloedema
check for MS sx- twitching, uncoordinated eye movements, slurred speech, Uhtoff’s phenomenon
Management of optic neuritis
do MRI- may resolve spontaneously in MS
abx if infectious
high dose corticosteroids over 4-6 weeks
presentation of herpectic keratitis
Eye pain, redness. **Grittiness Watery discharge. Blurred vision. **Sensitivity to light. lid oedema
^^ these are sx of any microbial keratitis / corneal ulcer !
- **oral lesions- ASK ABOUT THESE
- Contact lenses- likely to be pseudomonas aeruginosa, Acanthamoeba castellanii ( also causes photophobia)
- herpetic keratitis- dendritic ulcer
what ix do you do and what do you see for ?herpectic keratitis
fluorescein staining drops- you will see dendritic corneal ulcers
management of herpectic keratitis
acyclovir eye ointment
NO STEROIDS- thats for SHINGLES
what is ophthalmic shingles
Varicella zoster virus lies dormant in the sensory ganglion of the V nerve- reactivated and travels down the 1st branch )ophthalmic N)
What is Hutchinson’s sign of ophthalmic shingles and why does it occur
due to Herpes zoster ophthalmicus- reactivation of HERPES zoster over ophthalmic division of CN V
If the shingles involves the nasociliary branch of the Ophthalmic nerve.– vesicles on the tip of the nose
Management of Ophthalmic shingles
Admit
oral acyclovir within 72 hours of rash onset
if significant eye involvement- steroid eye drops
ophthalmic shingles sx
vesicular rash and prodromal pain over area of ophthalmic branch of V
unexplained redness of the eye, changes in vision
What is Ramsay Hunt Syndrome
VARICELLA Zoster virus involving the VII nerve
sx- UL painful vesciular rash around 1 ear
UL facial pain/weakness
hearing loss, vertigo
Dry eyes, difficulty closing the eye
sx of retinal artery occlusion
sudden loss of vision (total if central artery occlusion, superior/inferior loss if branch artery occlusion)
Relative afferent pupillary defect (affected eye responds different to light stimuli when compared to the other)
ix for person with sudden loss of vision, with PMHx of hTN, DMT2, smoker. What ix would you do? What would you see if your main differential is correct
?retinal artery occlusion
- fundosocopy - cherry red spot on a pale retina
- could do a carotid doppler if ?cause
Management of retinal artery occlusion
vision cannot be saved once ischaemia has occurred
prevention of further events:
- aspirin
- Bp meds
- statins
sx and signs of retinal vein occlusion
blurring of vision, visual field defect
Central vein: sudden UL visual loss, cheesy pizza on fundoscopy
painless
may have afferent pupillary defect
what would you see on fundoscopy and testing in someone with retinal vein occlusion
- ***optic disc swelling
- **RAPD
- severe flame haemorrhages (arery occlusion would be cherry red spots)
- cotton wool spots
what other ix would you need other than fundoscopy for ?retinal vein occlusion
fundus fluorescein angiogram
tx retinal vein occlusion
pan-retinal photocoagulation
dexamethasone and anti-vEGF implants if neovascularisation occurs (risk of vitreous haemorrhage)– ((((Anti–vascular endothelial growth factor therapy,)))
what is your main differential in someone with floaters/dark spots, a red hue, followed by obscured/loss of vision
vitreous haemorrhage– secondary to retinal vein occlusion, leading to neovascularisaiton, retinal detachment/tears
Vitreous haemorrhage sx
- sudden appearance of spots, floaters, shadows
- sudden blurring of vision, red tint
- sudden blindness
- eyesight worse in morning (blood pooling)
Management of vitreous haemorrhage
- generally get better on their own
- virectomy
A man with COPD and HTN comes to your GP practice with a sudden onset, UL, painless bright red area on his eye- main differential and management
Subconjunctival haemorrhage
- check for other injuries if due to trauma
- check for coagulopathies if spontaneous
- avoid aspirin/nsaids
resolves on it’s own
Mechanism of diabetic retinopathy
microangiopathy in capillaries- occlusion and ischaemia
new blood vessel formation on the iris
bleeding of the new blood vessels- increased risk of reintal detachments
Pattern of blindness in diabetic retinopathy
cotton woll spots, all visual fields
what do you see on fundoscopy in diabetic retinopathy
- haemorrhages
- microaneurysms
- cotton wool patches (retinal infarction due to capillary occlusion)
- oedema
Management of diabetic retinopathy
ctonrol BP, glucose
laser photocoagulation and anti-vEGF
what is the macula
part of the retina, found lateral to optic disc, site of highest visual acuity. At the centre of the macula you have the fovea
Different types of macular degeneration
dry- retina atrophy
wet- new vessel growth under the retina
presentation of macular degen
dry- Macular-Middle!
- CENTRAL SCOTOMA (blind spot/vision loss) with ok peripheral vision
- loss of colour differentiation
- may be worse at night and fluctuate daily
wet-
- more rapid changes in vision, (MONTHS) , with a sudden deterioration recently.
- central scotoma
- flashing, glares off lights at night
- floaters
- Objects become smaller
- lines not appearing as straight
- can still have central scotoma
ix of ?macular degen
slit lamps
colour fundus photography
ocular coherence tomography
management of macular degen
dry- vit A, C, E, zinc, stop smoking
wet- photocoagulation, anti-VEGF (eg ranibizumab), Intravitreal injections of anti-TNF beta
where is the aq humour made and drained
made- ciliary bodies
travels through pupil into the anterior chamber
drains- through trabecular meshwork, flows into the canal of Schelmn (angle)
what is glaucoma and why does it happen
build up of fluid and increase in intra-ocular pressure
open angle:
- Aq outflow is reduced despite ant chamber angle being open
- More common in older patients obstruction of the angle
eye is producing too much fluid
closed angle
- ant chamber drainage (angle) is closed
what is intraocular pressure in glaucoma
> 21mmHg
sx and signs of chronic open angle glaucoma
often asymptomatic
optic nerve compression- loss of sight /visual field defects
TUNELLING of vision as PERIPHERAL vision is lost
NB: no haloing around lights (this is acute close angle glaucoma)
optic disc cupping on fundoscopy
What type of glaucoma is often asymptomatic
chronic open-angle glaucoma- picked up on screening
management of chronic open angle glaucoma
- prostaglandin analogue- latanoprost - improve flow
- BB timolol- reduce Aq prod.
- mitotic agent (parasymp)- pilocarpine - flow
- topical sympathomimetic alpha 2 agonist eg brimonidine- prod
- carbonic anhydrase inhibitor (acetazolaMIDE) - prod
definitive: laser therapy
surgery
presentation of acute angle closure glaucoma
UL eye pain headache nausea, vomiting poor vision, halos around lights signs: - mild dilated pupil - eye looks 'hazy' (corneal oedema) - reduced vision
complication- permanent loss of vision
tx of acute angle closure glaucoma
AIM: decrease Aq production, constrict the pupil.
- Lie pt flat
- IV acetazolamide (diamox)- carbonic anhydrase inhib, reduce aq humour prod
Combination eye drops:
- BB- timolol drops (reduce Aq humour production)
- pilocarpine- (ciliary contrraction, opens trabecular meshwork) /
- alpha 2 agonist eg brimonidine , apraclonidine (reduce a sectretion)
- (latanoprost)
definitive- surgery (iridotomy)
signs of cataracts
white pupil
loss of red reflex
can see grey not red through slit lamp
halos around lights
RFs for retinal detachment
diabetic retinopathy retinal tear vitreous haemorrhage/retinal vein occlusion eye surgery high myopia (short sightedness)
presentation of retinal detachment
3 Fs
Floaters
Flashes
Field defects- sudden, painless. often like a dark curtain/shadow. if you get superior detachment, visual field defect will be inferior
NB: dark spots +- floaters, red hue is vitreous haemorrhage
NB2: floaters/flashes without visual defect may be vitreous detachment
management of retinal detachment
seal retina with lasers
what is myopia, management
short sightedness- eye is too long
management- concave glasses
what is hypermetropia
long sightedness , eyeball is too short
too much ciliary contraction
what are you at increased risk of with myopia
(Near sightedness)
- retinal and vitreous detachment
- cataracts
- open angle glaucome
what is astigmatism
irregular lens/corneal surface so it is not perecftly curved. Light rays do not meet perfectly as a common foucs so images are perceived in a distorted fashion
What is your main differential with someone with night blindness followed by tunnel vision and poor visual acuity
what would you see on examination
tx
Xerophthalmia- decreased tear production, causing dry eyes. Due to Vit. A deficiency
See Bilots spots (foamy plaques) on conjunctiva
tx with vit A supplements
A 23 year old male presents with a boggy, tender, swollen inner canthus (skin mdeial to eye). It sometimes expresses pus when massaged. PMHx- recurrent conjunctivitis. what is your main differential
Nasolacrimal duct obstruction- dacryostenosis/dacryocystitis
management of dacryostenosis/dacryocystitis
blocked tear flow from lacrimal gland (above eyelide) or from nasolacrimal duct (below medial eye edge)
warm compress
nasolacrmial duct massage
abx if needed (pus)
surgery to restore flow of tears into nose from the lacrimal sac
What is strabismus
misalignment of the visual axes of the two eyes- they point in different directions
What is a manifest strabismus?
– present at rest
What is a latent strabismus
- a squint controlled by subconsious effort and so is not always apparent. In certain conditions eg fatigue, tetsing, the squint will manifest.
what are the different types of latent strabismus
Esophoria – looks inwards
Exophoria – looks outwards
Hyperphoria – looks upwards
Hypophoria – looks downwards
What are the different types of manifest strabismus
Esotropia- looks inwards
Exotropia- looks outwards
Hypertropia- looks upwards
Hypotropia- looks downwards
what is a pseudo squint
large epicanthic folds give the appearance of a squint
Causes of strabismus
hereditary
*refractive error- needs glasses, hypermetropia, anisometropia (eyes have varying refractive powers)
idiopathic
secondary visual loss
*neuro defects eg cerebral palsy
*neuro aetiology- raised ICP, CN palsy (III, IV, VI)
*febrile illness
what is amblyopia
lazy eye
ix for strabismus
corneal reflections
cover test- manifest or latent , direction of strabismus
visual acuity
ocular movements- exludes paralytic strabismus
what is the cover test
cover one eye and see if the other moves to focus on the target
uncover the eye and see that eye moves back
the pt will use the eye with the better visual acuity preferentially and allow these worse eye to point in the direction of the strabismus
what would you find on the cover test if someone has exotropia
(Manifest strabismus) when the aligned eye is covered, the misaligned eye will then focus on the point of focus. When the good eye is uncovered, the eye will then move out again to the position of strabismus. When the bad eye is covered, the good eye doesnt move
what would you find on the cover test if someone has exophoria
(latent strabismus) when an eye is covered, the eye will move out underneath the cover. When you remove the cover, you will see that eye moving back into alignment
management of strabismus
Conservative
- glassess/contacts
- convex for hypermetropia
- concave for myopia
- prisms
- orthoptic exercises
botulinum toxin to extraocular muscles- does wear off after few months
Surgical
- esotropia- medial recession resection (weakening)/UL medial rectus recession and lateral rectus resection
- exotropia- lateral rectus recession/UL lateral rectus recession and medial recust resection
A child comes into your clinic with sudden onset strabismus- what do you do
usually not sudden onset- urgently refer
check for other neuro signs
What CNs serve the eye and how?
CN II (optic)- sees
CNIII Occulomotor- all other extraocular muscles
CN IV Trochlear- Superior oblique
CN V Trigem- sensation (ophthalmic branch)
CN VI Abducens- lateral rectus
CN VII Facial– closes the eye (orbicularis oculi)
What are you likely to see on fundoscopy for dry macular degen
Drusen- white accumulations of extracellular matter
What are the differences in onset of the different types of macula degeneration?
Wet- subacute (weeks/days/months)
Dry- chronic (year)
In a pt with optic neuritis, what is likely to be present in their csf
MS- oligoclonal bands IgG
Differentials of a red eye
- bacterial/microbial keratitis
- Trauma
- **- Acute angle-closure glaucoma
- **- Uveitis
- Scleritis
- Herpes simplex keratitis
- subconjunctival haemorrhage
- Episcleritis
- conjuncitvitis
- blepharitis
- behcet’s- eye sx (red, pain, blurring), swollen/painful/stiff joints, painful genital/mouth ulcers
How would your hx and examination narrow down cause of red eye
- *- bacterial/microbial keratitis (contact lens wearer)
- *- Hx of trauma
- Acute angle-closure glaucoma- hypermetropia (long sighted), asian, N+V, headache, blurred vision with **haloes, hazy cornea, mid dilated pupil
- Uveitis- photophobia, small irregular pupil, hx of joint/back pain?
- Scleritis- **autoimmune diseases, severe eye pain, photophobia, eye watering
- Herpes simples keraitis- pain, photophobia, ***profuse watery discharge, dendritic ulcer
- Subconjunctival haemorrhage-bright red, no pain
- Episcleritis- uncomfortable, not very painful
- Conjunctivitis- discharge
Examination findings of hypertensive retinopathy
Bilateral:
1) Arteriolar constriction, tortuous vessels
2) Arteriolar nipping- due to atherosclerosis
3) microaneurysms, cotton wool spots, flame-haemorrhages
4) Papilloedema
sx of hypertensive retinopathy
usually asymptomatic
sometimes reduced vision due to disc swelling
tx hypertensive retinopathy
tx HTN
differentials of optic disc swelling
Papilloedema (swelling with raised ICP):
- space occupying lesions
- infection
- subdural/SAH
- hydrocephalus
- Idiopathic intracranial hypertension
- Dural venous sinus hypertension
Optic Disc swelling
- UL- optic neuritis
- retinal vein occlusion
- diabetic retinopathy
- hypertensive retinopathy
- non-arteritic anterior iscaemia optic neuropathy
ix for optic disc swelling
CT head/MRI to rule out intracranila processes
BP- HTN
LP
optic disc swelling sx and signs
asymptomatic visual acuity reduced colour vision affected headache, N+V sometimes enlarged blind spot
most common cause of sudden painless loss of visions
- ischaemic/vascular- retinal vein/artery occ
- Vitreous haemorrhage- vision of spots that are suspended in vision (floaters), blurred vision or complete and sudden loss of vision, red hue
- retinal detachment- flashes, floater, visual loss
- *- retinal migraine
- *- GCA
- *- TIA/stroke
NB: vitreous detachment doesnt cause loss of vision (only floaters/dark spots) unless then involves retina
RF for vitreous haemorrhage
diabetes
bleeding disorders
anticoags
contact lens wearer with a red, painful, gritty feeling eye. Watery discharge, systemically well- what do you do?
refer for same day ophthalmology assessment – could be conjunctivitis BUT contact lens wearer means bacterial keratitis must be ruled out
RFs to cataracts
hypocalcamia downs DM LT steroid use-- strongest RF for subcapsular cataracts uveitis age trauma
presentation of endophthalmitis
red eye
reduced vision
very painful
following intraocular surgery
what is endophthalmitis
inflammation to inraocular fluid due to infection
differences on fundoscopy wet vs dry
wet- - red patches on retina/subretinal haemorrhage (leakage of serous fluid/blood) - neovasculariation dry- - drusen are more common - Retinal pigment epithelium atrophy
when should you urgently refer a child with strabismus
red flags: nystagmus/oscillations double vision headaches limited abduction
what would you do as a GP for a child with strabismus
refer to ophthal . they will then have eye exercises, glasses, patches and maybe surgery
Amsler chart- what is it used for
macular degen
what does rhegmatogenous mean
a retinal detatchment with a clear retinal break on fundoscopy
Risk of steroid eye drops
can lead to fungal infections- which can lead to corneal ulcers/microbial keratitis
LT -cataracts
how does the hx and exmination of an acute glaucoma and anterior uveitis differ
Acute glaucoma- UL eye pain, haloing of light, fixed mild dilated pupil, hazy cornea!!!
ant uveitis- BL eye pain with photophbia, constricted pupils, may have hypopyon (pus in ant chamber)
UL miosis with lagging eyelid and shoulder/arm pain- main differential?
pancoast syndrome
hx- smoker
difference in presentation between vitreous haemorrhage and vitreous detachment
Haemorrhage- dark spots (loss of vision)/floaters with red hue to vision, painless, RF- diabetic
detachment- NO visual loss, flashes/floaters in peripheries. NO red hue
O/E, as the light is moved from a pt’s left eye to right eye, both pupils dilate. Reaction to accomodation is normal, fundocsopy is normal- What is the name of this sign, waht does it mean?
Marcus-Gunn Pupil/relative afferent pupillary defect.
Means damage to the afferent pathway (reinta or optic nerve)
What is an Adie pupil, whats is it caused by
- Tonically dilated pupil (BL or UL)
- slowly reactive to light
- often with absent knee/ankle reflexes
Causes: damage to parasympathetic due to viral or bacterial infection.
What is the name of the syndrome with UL miosis, ptosis, enophthalmos, anihidrosis. Cause?
Horner’s syndrome
Damage to ipsilateral sympathetic branch (trauma, compression, infection, ischaemia)
Central
- hypothal, brainstem, spinal cord
- stroke, glioma, syringomyelia
Preganglionic- (CANCERS plus TOS, T spine)
- *- thoracic outlet (cervical rib, subclav aneurysm
- mediastinal tumours
- pancoast tumour
- thyroid malignancies
- trauma to thoracic spinal cord
- surgery
post ganglionic- (SKULL/SINUS plus endart, cluster)
- trauma to cervical ganglion
- *- lesions of ICA in cavernous sinus- thrombosis, aneurysm, inflam, tumours
- skull base issues- dissection, thromosis, tumours
- endarterectomy
- cluster headaches
Anihidrosis is more pronounced in central and preganglionic causes
What is Hutchinson’s pupil, cause
UL dilated pupil unreactive to light
compression of occulomotor nerve ipsilaterally by intracranial mass (tunour, haematoma)
What is Argyll-Robertson pupil, causes?
BL small pupils that accommodate but dont react to light
cause- syphillis, DM
management of man with vesicular rash on tip of his nose and eye pain
same day ophthalmology assessment- Hutchinson’s sign suggests pending eye inflammation, permanent corneal denervation and anterior uveitis !
what would be found in R esotropia on cover test?
on covering the L eye, the R eye moves laterally to take up fixation
what do you see on fundoscopy with ?raised ICP
papilloedema-
- venous engorgement
- optic disc margin blurring
- loss of optic cup
- loss of venous pulsation
- elevation of disc
- Paton’s lines (circumferential retinal folds around the optic disc)
RF for retintal vein occlusion
diabetes
a pt comes in following being hit in the face with a baseball bat- o/e, the r eye has blood in the anterior chamber- this puts him at increased risk of what?
Glaucoma
Blunt ocular trauma with hyphema is high risk scenario for raised intraocular pressure
what complications are there following blunt trauma to the eye
Glaucoma (esp if hyphema)
cataract
ectopia lentis (dislocation of lens)
what to cycloplegic drugs do
dilate the pupil (mydriatic)
presentation and signs of subcapsular cataract
fast progression
glare from bright lights
central granular lens opacity O/E
?orbital cellulitis- what imaging should be done to confirm the dx and evaluate further complicaitons
contrast enhanced CT scan of the orbits, sinuses and brain- to assess the posterior spread of the infection
symptoms of retinitis pigmentosa
night blindness
tunnel vision
which has the worst prognosis- wet or dry mac degen?
wet
explain snellens visual acuity scoring
visual acuity = test distance (meters)/letter size (M)
letter sizes go from 0.5 (smallest) to 6 (largest)
eg 6/6 means 6 metres from chart, pt could see 6M sized letter
4/6 means from 4 metres from chart, pt could see 6M letter (reduced vision as pt needed to be closer to the chart
6/6 is equivalent to 20/20 vision
vitreous vs retinal detatchment
vitreous- flashes, floaters, no visual loss
retinal- flashes, floater and visual loss
how does timolol work
reduces aq production
TOP
what class is acetazolamide and how does it work
MIDE- Carbonic anhydrase
reduces aq production
IV
what class is latanoprost and how does it work
prostaglandin
increases uveosceral outflow
TOP
what class is brimonidine and how does it work
DINE- alpha2 adrenoreceptor agonist
increases uveoscleral outflow
TOP
screening for those with fam hx or of black african heritage for glaucoma
annually from 40yo
eye conditions of tertiary syphillis
uveitis
optic neuritis
what is an ectropion of the eye
- eyelid droops away from eye and turns out
- usually not serious
- can be uncomfortable
- eye watering
- dry, grittiness
- can increase risk to bacterial infections
tx
- lubrication
- tape at night
- surgery
difference between horners and CNIII palsy
horners- ptosis and constriction
CNIII- ptosis and dilation!!!!, out and down
management of meningitis in hospital
ceftriaxone, cefotaxime or chloramphenicol
if less than 3-months old />50y
- you would use cefotaxime instead of ceftriaxone.
- +amoxicillin
dexamethasone
