OCULAR CONDITIONS Flashcards
AMD RISK FACTORS
age (>50)
smoking
female
caucasians
UV exposure
family history
poor diet
WHERE DOES DRY AMD BEGIN?
Bruch’s membrane
BRUCH’S MEMBRANE ROLE
it is located between RPE and vascular choroid
RPE layer allows waste products from photoreceptors to move through Bruch’s membrane where they are cleared away by choroidal BVs
BLEPHARITIS TYPES
staphylococcal - crusting at anterior lid margin
seborrhoeic - oily/ greasy deposits on lid margin
demodex - cylindrical dandruff (collarettes), type of mite
meibomian gland dysfunction - blocked oil glands
AC cells convection current
cells move upwards at back of eye and downwards at front of eye
warmer at back of eye
keratic precipitates
inflammatory deposits
large mutton fat - more suspicious px has granulomatous uveitis and has underlying systemic cause
small fine KPs - more likely idiopathic
ANTERIOR CHAMBER CELLS GRADING
grade 0 = no cells
grade 0.5+ = 1-5 cells
grade 1+ = 6-15 cells
grade 2+ = 16-25 cells
grade 3+ = 26-50 cells
grade 4+ = >50 cells
ANTERIOR CHAMBER FLARE GRADING
grade 0 = no flare
grade 1 = faint flare
grade 2 = mod flare (iris + lens clear)
grade 3 = marked flare (iris + lens hazy)
grade 4 = intense flare (fibrin or plastic aqueous)
recurrent vs chronic anterior uveitis
recurrent = repeated episodes separated by periods of inactivity without treatment or 3+ months
chronic = persistent uveitis characterised by prompt relapse (<3/12) after discontinuation of therapy
ANTERIOR UVEITIS AETIOLOGY
- autoimmune (systemic disease)
- prior infections (HS, HZ)
- idiopathic
- external injury/ infection
- intraocular surgery
SYSTEMIC CONDITIONS ASSOCIATED WITH ANTERIOR UVEITIS
ankylosing spondylitis
juvenile idiopathic arthritis
inflammatory bowel disease
sarcoidosis
non-granulomatous vs granulomatous anterior uveitis
non-granulomatous = acute onset, fine KPs, more likely idiopathic
granulomatous = chronic condition, large ‘mutton fat’ KP + iris nodules, more likely associated with systemic conditions
IRIS NODULES
iris nodules represent accumulations of inflammatory cells
Koeppe - found at pupillary border
Busacca - further from pupil, systemic causes
ANTERIOR UVEITIS MANAGEMENT
instil cyclopentolate 1% drops to relieve pain + prevent posterior synechiae
emergency referral for topical steroids - prednisolone 1% every hour + cyclo 3x daily; px reviewed in 24 hours
KERATOCONUS
non inflammatory progressive ectasia of cornea causing an irregular thinned corneal shape
keratoconus risk factors
asian ethnicity, family history, collagen/ connective tissue disorders, atopy, eye rubbing
dry AMD management
no treatment - aim is to slow down progression
advise on nutritional supplements
stop smoking
leafy green veg
amsler - self monitoring
wet AMD treatment
urgent referral for intravitreal anti VEGF injections if VA better than 6/60
laser photocoagulation
photodynamic therapy
ANTI VEGF injections
these inhibit activation of VEGF receptors to inhibit new vessel growth
Ranibizumab (Lucentis), Aflibercept (Eylea)
3 doses injected every 4 weeks
AMAUROSIS FUGAX
temporary loss of vision in one or both eyes due to lack of blood flow to retina
OXIDATIVE STRESS
imbalance of free radicals and antioxidants in the body
DR PATHOGENESIS
high blood sugar -> oxidative stress, inflammation, hypoxia -> VEGF production -> promotes growth of new leaky BVs
why is VEGF stimulated?
oxygen deprivation
