opthalmology Flashcards
types of conjunctivitis
infective (bacterial and viral) And allergic
presentation of allergic conjunctivitis vs infective
allergic is bilateral from the start, seasonal, history of atopy, swollen eyelids sometimes, itchy, — infective has more sticky discharge and other stuff
bacterial conjunctivitis presentation
purulent sticky discharge
eyes stuck together in morning
viral conjunctivitis presentation
serous discharge, pain, preauricular lymph nodes, recent URTI,
management of conjunctivitis
usually settles without treatment but topical antibiotics commonly prescribed - chloramphenicol - fusidic acid if pregnant
something to do for contact lens users with conjunctivitis
use topical fluoresceins to identify corneal stain
optic neuritis top causes
MS, diabetes, syphilis
features of optic neuritis
unilateral decrease in visual acuity– fast progression: over hours/. days
and bad colour differentiation,
central scotoma,
increased pain on movement,
and RELATIVE afferent pupillary defect
diagnostic investigations of optic neuritis
MRI of brain and orbits -
when is there a 50% 5 year predicted risk of developing MS?
when they have optic neuritis with more than 3 white matter lesions seen on MRI
scleritis pathophysiology
inflammatory condition - non infective- all layer inflammation of sclera
anatomically what is sclera and what is episclera
sclera is all outer layers of eyeball from episclera to epithelium so scleritis more erious and deep than episcleritis
scleritis associated conditions
RA and SLE
Features of scleritis
red eye, pain, photophobia + watery, gradual decrease in vision
management of scleritis
urgent same day rederral to ophthalmologist, usually oral NSAiDS first lne and glucocorticoids if severe
immunosupression if really severe
episcleritis pathophysio and causes/ associated conditions
idiopathic and inflammation of episclera - sometimes associaeted with IBS and RA
features of episcleritis
red eye, less pain, vessels can be moved with mild pressure vs not in scleritis, no decrease in visual acuity, 50% is bilateral
what eye drop canhelo distinguish episcleritis from scleritis
phenylephrine drops
management of episcleritis
conservative– maybe aritificial tears
anterior uveitis presentation
constricted pupil!! Acute onset: pain, reduced visual acuity progressively worse, red, lacrimation, ciliary flush (red from in out), hypopyon, (pyon below surface and you can tell) ,
anterior uveitis associated conditions
ankylosing spondylitis !! think anterior uveitis only eye condition starting with a so Ankylosing spond
reactive arthritis
UC, Crohn’s
sarcoid
management of anterior uveitis
urgent ophthalmology referral, cycloplegics, steroid eye drops
with what antigen on white blood cell walls is anterior uveitis associated with?
HLA-B27
conditions associated with HLA-B27
seronegative spondyloarthrites, meaning spondyloarthritic conditions that do not have rheumatoid factor: AS, reactive arthritis (RA, previously referred to as Reiter syndrome), Behçet’s disease, inflammatory bowel disease (IBD), and psoriatic arthritis (PA).
visual field defect types
1) homonymous hemianopia
2) homonymous quandrantanopia
3) bitemporal hemianopia
3 connections of nerves in visual pathway
1) optic nerve ending in eye, 2) optic tract (optic chiasm happens at that stage) 3) optic radiation
what lesions lead to a right homonymous heamianopia
left optic tract lesion,
left optic radiation lesion or occipital cortex
with macular sparring: left occipital cortex
what lesions lead to a right upper homonymous quadrantanopia
left temporal -lower tract lesion
what lesions lead to right lower homonymous quadrantanopia
left parietal- upper tract lesions
bitemporal hemianopia lesion and upper lower predominance
lesion on optic chiasm
if impairment worse in UPPER fields then LOWER lesion so pituitary vs if LOWER fields impaired UPPER problem so craniopharyngioma
thyroid eye disease pathophysiology
auto antibodies possibly to TSH receptors deposit on eye muscles at the back of the orbit
thyroid eye disease features and situation of thyroid disease at presentation
exophthalmos
dry eyes due to inability to close eyes
ophthalmoplegia (paralysis of eye muscles)
conjunctival oedema
optic disc swelling
thyroid disease situation irrelevant, may be eu- hypo or hyperthyroid
which thyroid condition is eye disease linked with (25-50% of people with this disease get the eye disease)
graves thyroiditis
main risk factor of thyroid eye disease and another one
smoking
radioiodine treatment of graves
management of thyroid eye disease
smoking cessation
steroids
topical lubricants may be needed to help prevent corneal inflammation caused by exposure
surgery
radiotherapy
complications of thyroid eye disease
exposure keratopathy
optic neuropathy
strabismus and diplopia
Monitoring patients with established thyroid eye disease - red flags to safety net for and look out
unexplained deterioration in vision
awareness of change in intensity or quality of colour vision in one or both eyes
history of eye suddenly ‘popping out’ (globe subluxation)
obvious corneal opacity
cornea still visible when the eyelids are closed
disc swelling
most common form of diabetic eye disease and second and third commonest
diabetic retinopathy
diabetic maculopathy
diabetic cataract
pathophysiology of diabetic retinopathy
a) hyperglycaemia leads to endothelial and pericyte damage
1) ENDOthelial damage means more permeable endothelium hence exudates
2) pericytes are cells around cappilaries in eye so damage leads to aneurisms
b) neovascularisation due to growth factor release because of ischaemia
non proliferative diabetic retinopathy classifications and features
Mild NPDR
1 or more microaneurysm
Moderate NPDR
microaneurysms
blot haemorrhages
hard exudates
cotton wool spots (‘soft exudates’ - represent areas of retinal infarction), venous beading/looping and intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR
Severe NPDR
blot haemorrhages and microaneurysms in 4 quadrants
venous beading in at least 2 quadrants
IRMA in at least 1 quadrant
proliferative diabetic retinopathy
retinal neovascularisation - may lead to vitrous haemorrhage
fibrous tissue forming anterior to retinal disc
more common in Type I DM, 50% blind in 5 years
maculopathy features
Key features
based on location rather than severity, anything is potentially serious
hard exudates and other ‘background’ changes on macula
check visual acuity
more common in Type II DM
management of diabetic eye disease
All patients
optimise glycaemic control, blood pressure and hyperlipidemia
regular review by ophthalmology
maculopathy management in case of change in case of change in visual acuity?
ntravitreal vascular endothelial growth factor (VEGF) inhibitors
Non-proliferative retinopathy managemnt
regular observation
if severe/very severe consider panretinal laser photocoagulation
Proliferative retinopathy management
1) panretinal laser photocoagulation
following treatment around 50% of patients develop a noticeable reduction in their visual fields due to the scarring of peripheral retinal tissue
a decrease in night vision
2) intravitreal VEGF inhibitors
often now used in combination with panretinal laser photocoagulation
examples include ranibizumab
3) if severe or vitreous haemorrhage: vitreoretinal surgery
orbital cellulitis pathology
infection affecting the fat and muscles posterior to the orbital septum, within the orbit but not involving the globe.
orbital cellulitis common cause / history
previous URTI
PRE ORBITAL cellulitis pathology and relation to orbital
Periorbital (preseptal) cellulitis is a less serious superficial infection anterior to the orbital septum, resulting from a superficial tissue injury (chalazion, insect bite etc…). Periorbital cellulitis can progress to orbital cellulitis.
orbital cellulitis risk factors
Childhood
Mean age of hospitalisation 7-12 years
Previous sinus infection
Lack of Haemophilus influenzae type b (Hib) vaccination
Recent eyelid infection/ insect bite on eyelid (periorbital cellulitis)
Ear or facial infection
features orbital cellulitis
Redness and swelling around the eye
Severe ocular pain
Visual disturbance
Proptosis
Ophthalmoplegia/pain with eye movements
Eyelid oedema and ptosis
Drowsiness +/- Nausea/vomiting in meningeal involvement (Rare)
differences bwtween orbital and periorbital
reduced visual acuity, proptosis, ophthalmoplegia/pain with eye movements are NOT consistent with preseptal cellulitis
diagnostics of orbital cellulitis
Full blood count - WBC elevated, raised inflammatory markers.
Clinical examination involving complete ophthalmological assessment - Decreased vision, afferent pupillary defect, proptosis, dysmotility, oedema, erythema.
CT with contrast - Inflammation of the orbital tissues deep to the septum, sinusitis.
Blood culture and microbiological swab to determine the organism. Most common bacterial causes - Streptococcus, Staphylococcus aureus, Haemophilus influenzae B.
management of orbital cellulitis
admission to hospital for IV antibiotics
