red eye Flashcards
where is aqueous humour drained
- 85% through the conventional pathway (trebecular meshwork, IOP dependent)
- 15% through uveoscleral pathway (IOP independemt)
2 most important things hen taking a Hx of red eye
- onset (duration, location, laterality);
- associated symptoms (pain, itching, discharge, visual change)
what are the 4 “coats” that comprise the external eye
- eyelids
- conjunctiva
- episclera
- sclera
what is the most common eyelid cause of red eye
herpes simplex virus - can manifest w conjunctivitus
treatment for herpes simplex eyelid infection
topical acyclovir - quickly resolves
what is an internal hordeolum and how is it treated
an internal style, treat with hot compress
how does blepharitis present
gritty eye; increased watering of eye; red eye; discharge along root of the lashes (if anterior blepharitis)
blepharitis treatment (3)
- hygeine (johnsons baby shampoo to clean around lacrimal glands)
- oral doxycyline is severe inflammation
- steroid/abx drops
what can blepharitis develop into
marginal keratitis
what is marginal keratitis
inflammatory reaction to the staph growing in the eye lid - a cross reaction
what is a cross reaction
reactivity of an observed agent which initiates reactions outside the main reaction expected e.g. allergies
what happens to the eye in marginal keratitis
ulceration of the lateral cornea
marginal keratitis treatment (2)
- topical steroid
- topical Abx
what is entropion
rolling inward of the eyelid against the eyeball which can cause infection
what is herpes zoster ophthalmicus
unilateral painful skin rash in one or more dermatome distributions of CN V (trigeminal nerve), shared by the eye and ocular adnexa
what is hutchingson’s sign
an early indicator of ophthalmic (eye) shingles -> It refers to painful vesicles or bumps at or near the tip of your nose
what eye condition is common as a result of herpes zoster ophthalmicus (esp if hutchingson’s sign)
uveitis
herpes zoster ophthalmicus treatment
- oral acyclocir (5x a day for a week);
- topical steroids (for inflammation)
what is molluscum contagiosum (eye)
umbilicated lesions along the lid margin, common in children
treatment of molluscum contagiosum (eye)
quick curettage of the lesions to stop them spreading
what are the 2 types of conjunctivitis and which is a cause for concern
- conjunctival congestion (widespread, all around the cornea);
- perilimbal congestion (circumconeal congestion - red blood cells pointing towards the cornea)
this is a cause for concern -> corneal infection, gluacoma etc.w
what can cause conjunctivitis (4)
- bacteria (simple, gonococcal);
- viral (adenoviral, molluscum, herpes);
- chlamydial;
- allergic/vernal
simple bacterial conjunctivitis presentation (5)
- crusted eyelids
- conjunctival injection
- red eye
- discharge (mucopurulent)
- eyelashes stuck together in the morning
how can conjunctivitis be treated
topical abx + good hygeine (e.g. not sharing towels)
when should gonococcal conjunctivitis be a cause for concern
if neonatals get it- can be life threatening
gonococcal conjunctivitis treatment
systemic cephalosporins and topical Abx drops
what is follicular conjunctivitis
collection of lymphoid tissue usually due to a viral or chlamydial conjunctivitis
2 types of adenoviral keratoconjunctivitis, who they usually affect and what other symptoms
- pharyngoconjunctival fever - adenovirus types 3/7; affects children; upper resp tract infection associated;
- epidemic keratoconjunctivitis - types 8/19; very contagious; no systemic symptoms; keratitis in 80% of cases
what is keratitis
inflammation of the cornea and is characterized by corneal edema, infiltration of inflammatory cells, and ciliary congestion
what is trachoma
a disease of the eye caused by infection with the bacterium Chlamydia trachomatis (serotypes A, B, Ba, C)
what is a major vector for trachoma
flies
treatment for trachoma
systemic azithromycin
7 complications of trachoma
- acute follicular conjunctivitis;
- conjunctival scarring;
- herbert pit;
- pannus formation;
- trichiasis;
- cicatricial entropion;
- loss of vision
what is a pannus
growth of blood vessels into the peripheral cornea
what is a herbert pit
When infectious follicles heal, they are replaced by rounded, depressed, or flat scars aka herbert pitss
what causes adult chlamydial keratoconjunctivitis and what is it accompanied with
infection with chlamydia trachomatis serotypes D-K; usually alongside genital infection
treatment for adult chlamydial keratoconjunctivitis
topical tetracycline + oral tetracyclinr/macrolide + prompt sexual health referral
what is allergic rhinoconjunctivitis andw hat is it associated with
hypersensitivity reaction to specific air born antigens; may be seasonal/perennial; assoicated with nasal symptoms
what is vernal/atopic keratoconjunctivitis
a recurrent, bilateral allergic inflammation of the conjunctiva; frequently associated w atopy
treatment for vernal/atopic keratoconjunctivitis (4)
prompt treatment with:
1. antihistamines (topical/opetimol);
2. cold compress;
3. lubricant to help wash out inflammation;
4. steroids if severe
vernal/atopic keratoconjunctivitis presentation (2)
- upper tarsal giant papillae - lots of small papillae join together;
- thickening and opacification of the limbal conjunctiva as well as gelatinous appearing and sometime confluent limbal papillae;
what is pterygium
a raised, wedge/wing-shaped growth of the conjunctiva that extends onto the cornea, normally on the nasal side
pterygium/pingueculum treatment
surgical removal
what is hyphema
blood pooling behind the cornea and iris
pingueculum vs pterygium
Pinguecula may contain deposits of protein, fat, or calcium;
Pterygium is a growth of fleshy tissue (has blood vessels) that may start as a pinguecula
2 causes for sub conjunctival haemorrhage
- spontaneous - poss due to increased BP (so check BP)
- trauma
what is episcleritis
swelling and reddening of the outer sclera
episcleritis presentation
gritty, uncomfortable eye
epidcleritis treatemnt
may self resolve, otherwise give topical steroids to treat; investigations may be warranted if recurring
what is sceleritis
inflammation of the sclera - deeper vessels
causes of scleritis
usually and underlying systemic cause e.g. syphillis, RA, SLE -> investigate if not resolving
scleritis presentation
severe pain in the eye and eye is tender to touch
scleritis progression (3)
- avascular patches
- scleral necrosis and visibilty of uvea
- spread and coalescence of necrosis
scleritis treatment (3)
- oral steroids
- immunosuppressive agents e.g. cyclosporin, azathioprine etc.
- combined IV steroids and cyclophosphamide (if unresponsive)
what is photophobia
discomfort in bright light - light goes through the axis and causes a glare
what condition is photophobia most commonly seen in
uveitis
when should fluoroscein be used
as a tracer in cornea/kerat- abrasions/abnormalities
what is a corneal abrasion
scratched cornea
corneal abrasion treatment
promt treatment needed -> topical abx, should resolve without complications
what is photokeratitis (arc eye/snow blindness)
painful condition arising from the exposure of the eye to UV light -> extreme photophobia is present and it is often self resolving
4 types/causes of keratitis
- bacterial
- viral
- acanthamoeba
- fungal
what is a risk factor for keratitis
contact lens wearing (esp w poor hygeine)
bacterial keratitis presentation
severe, painful, photophobic eye
bacterial keratitis investigations
scrapings to find pathogen
pathology of bacterial keratitis (advanced)
inflammatory cells within the eye come together to forma hypopyon (accumulation of white blood cells that form a whitish layer of fluid in the lower portion of the eye’s anterior chamber)
viral keratitis presentation
multiple white disc shaped lesions; can last for months-years
viral keratitis treatment (2)
- topical steroids - UNLESS HSV causing (but usually recurs one stopped)
- topical lubricants
herpes simplex keratitis presentation
dendritic ulcer (branching pattern on the corneal epithelium); eye pain; swollen epithelial boarders;
herpes simplex keratitis managment
occasionally self limiting -> otherwise acylovir
avoid steroids
3 behaviours contact lens wearers do which may result in acanthamoebe karatitis
- poor hygeine with extended wear lenses;
- washing lens in tap water;
- wearing lenses for swimming
acanthamoebe karatitis presentation
very painful eye; grey-dirty epithelium; multifocal stromal infiltrates; ring infiltrates; scleritis + iris atrophy (late stage)
acanthamoebe karatitis treatment
topical cationic antiseptic - very resistant to treatment though
what workforce is fungal keratitis common in
farmers (aspergillous)
fungal keratitis presentation
elevated edges, branching ulcers, feathery margins, rough texture, and satellite lesion
fungal keratitis Mgx
Topical antifungals; Subconjunctival injections of antifungal agents e.g. miconazole if not compliant; systemic antifungal if resistant;
slow to heal and needs long term management
what is irisitis/anterior uveitis and how does it present
swelling/inflammation of the iris; presents with eye pain, blurry vision and possibly abnormally shaped pupils
iristitis managment
- topical steroids;
- cycloplegic drops (temporarily paralyzes the ciliary body)
does not tolerate eye drops
what is endophthalmitis
inflammatory condition of the intraocular cavities (ie, the aqueous and/or vitreous humor)
what is pupillary block and what can it lead to
the flow of aqueous humor from the posterior chamber to the anterior chamber is obstructed by a functional block between the pupillary portion of the iris and the lens -> increased pressure from the posterior chamber causes iris bombe (pressure in the posterior chamber rises, resulting in anterior bowing of the peripheral iris and obstruction of the trabecular meshwork) -> IOP is raised -> leads to acute angle-closure glaucoma
