the conjuctiva and sclera Flashcards
what are the three anatomical parts of the conjunctiva ?
the palpebral conjuctiva
the forniceal conjuctiva
the bulbar conjuctiva
what are the components of the conjunctiva ?
non keratinizing stratified squamous cell epithelium
goblet cells
substantia propria
what is the junction between the conjunctiva and the sclera called ?
the cornoscleral limbus
what are the different types of conjunctival reactions ?
hyperemia - conjunctival injection
chemosis - conjunctival oedema
subconjuctival hemorrhage
follicles
papillae
what are the features of conjuctival injection ?
hyperemia that extends away from the limbus
what are the causes of chemosis ?
acute: allergic reactions
chronic : thyroid eye disease, right sided heart failure and nephrotic syndrome
what are the causes of subconjuctival haemorrhage ?
viral conjunctivitis
valsalva or trauma
hypertension and diabetes
idiopathic
bleeding disorders
what are the causes of membrane formatiion ?
adenovirus
steven johnson syndrome
gonococcal conjuctivitis
how can you differentiate between a pseudomembrane and a true membrane ?
pseudomembrane can be peeled leaving behind an intact epithelium
A true membrane if peeled will leave behind a torn epithelium
what are follicles ?
multiple, discrete and translucent slightly elevated lesions that resemble translucent grains of rice, most prominent in the fornices
what are the causes of follicles ?
viral or chlamydiayal conjuctivitis
hypersensitivity to topical medications
what are papillae ?
can develop only in the palpebral conjunctiva and limbal bulbar conjunctiva
what are the causes of papillae ?
bacterial or allergic components
contact lens wearers
floppy eye syndrome
what are the classifications of conjunctivitis ?
infective
allergic
iatrogenic
what are the causes of bacterial conjunctivitis ?
strep pneumoniae
h influenza
what are the symptoms of bacterial conjunctivitis ?
redness
foreign body sensation
discharge which is usually bilateral but one eye may precede the other ( mucopurulent discharge)
vision is usually normal
what must be done in cases of suspected meningococcal or gonococcal infection ?
conjunctival swab
what must be done in cases of chlamydia or viral infections ?
PCR
what is the treatment for bacterial conjunctivitis if thee causative organism is not h.influenza , or gonococcal infection ?
topical antibiotics 4 times a day
either chloramphenicol, aminoglycosides, quinolone or macrolides
what is thee treatment for bacterial conjunctivitis caused by
h.influenza
gonococcal infection
meniingococcal infection ?
h.influenza :amoxicillin / clavulanic acid
gonococcal : 3rd generation cephalosporins
meningococcal : benzyl penicillin , ceftriaxone or ceftraxime IM can be used
what type of transmission or type of infection is adult chlamydial conjunctivitis ?
occulogenital infection
transmission is auto inoculation from genital secretions
what are the serological variants associated with adult chlamydia infection ?
D-K
what is the incubatioin period for adult chlamydia infection ?
app one week
what is the most common causee of non gonococcal urethritis in males ?
chlamydia
what are the symptoms associated with adult chlamydial infection ?
subacute unilateral or bilateral redness
watering and or discharge
what are the signs associated with adult chlamydial infection ?
watery or mucopurulent discharge
tender pre auricular lymphadenopathy
large follicles most prominent in the inferior fornix
superficial punctate keratitis is common
superior corneal pannus
mild conjuctival scarring
what are the investigations for a case of suspected adult chlamydia conjunctivitis ?
tarsal conjuctival scraping for geimsa stain
what would a positive giemsa stain for adult chlamydial conjunctivitis show ?
basophilic inclusion bodies in epithelial cells
lymphocytes in newborns
what is the treatment for adult chlamydial infection ?
referral to a genitourinary specialist
systemic ab- azithromycin 1g repeated after 1 week is the treatment of choice , topical antibiotics are not enough
reduce risk of transmission - no sexual activity until treatment is over
re-test in 6-12 weeks
what are the alternatives to azithromycin in ACC ?
erythromycin
amoxicillin
ciprofloxacin
what are the associated factors with trachoma ?
overcrowding
poor hygiene
flies are an important factor
what type of response is associated with a trachoma infection ?
delayed hypersensitivity type 4
what is the causative organism in Trachoma ?
also chlamydia but strains A to C
what are the stages of trachoma divided into ?
active stage ( acute)
cicatricial stage ( chronic )
what are thee features associated with the active form and stage of trachoma ?
common in pre school children
presents with both papillae and follicles
associated with mucopurulent discharge
in children under the age of 2 - papillary + pannus formation
what is pannus ?
vascular invasion that occurs on the periphery of the cornea
what are the features of cicatricial trachoma ?
common in middle aged patients
linear conjunctival scars called Arlts line
superior limbal follicles - Herbert pit
trichiasis
cicatrization - formation of scar tissue
cicatricial entropion - eyelids turn toward the globe due to fibrosis
corneal opacification
dry eyes due to destruction of goblet cells
what is the grading system for trachoma ?
TF - A few follicles in the superior tarsal plate
TI - follicles and papillae
TS - corneal scaring and Arlts lines
TT - Trichiasis
CO - reached corneal opacity
what is the management for trachoma ?
SAFE
Surgery to relieve entropion and trichiasis for complete lid closure
Antibiotics for thosee affected and family members - azithromycin
Facial cleanliness
Environmental improvement
what is the most frequent causative agent for viral conjunctiivitis ?
adenovirus
how is adenoviral conjunctivitis transmitted ?
transmission generally by contact with respiratory or ocular secretions
what is the most common clinical form of viral conjunctivitis ?
non-specific acute follicular conjunctivitis which is usually due to adenovirus
history of URTI and then presents with viral conjunctivitis ?
pharyngoconjunctival fever
most severe adenoviral conjunctivitis ?
epidemic keratoconjunctivitis
what is the causative organism in acute haemorrhagic conjunctivitis ?
tropical areas
enterovirus
coxsackievirus
what are the signs of viral conjunctiivitis ?
watery eye discharge
eyelid oedema
lymphadenopathy
conjunctival hyperemia
conjunctival follicles
what sign is specific to adenoviral conjunctivitis ?
keratitis
what signs are seen in molluscum contagiosum ?
pale waxy nodule on the lid of the margin
follicular conjunctivitis
what is the treatment for viral conjunctivitisi ?
adenoviral is self limiting within 2-3 weeks
reduce transmission risk , hawi 3al 3ayan
discontinuation of CL
what are the types of allergic conjunctivitis ?
acute allergic conjunctivitis
seasonal allergic conjunctivitis
perennial allergic conjunctivitis
what is the hallmark of allergic conjunctivitis ?
chemosis
what are the seasonal associations with allergic conjunctivitis ?
acute allergic - spring and summer
seasonal allergic - hay feever eyes - spring and summer - pollen
perinneal allergic conjunctivitis - autumn - but less severe - pets in the house
what is the immune response associated with vernal keeratoconjunctivitis ?
IgE and cell mediated immunity
what is the treatment for allergic conjunctivitis ?
avoidance of allergen first
if mildd - artificial tears
moderate - mast cell stabilizers or antihistamine
severe - topical steroids
what are the classifications of VKC ?
palpebral VKC - upper tarsal conjunctiva with papillae
LImbal VKC - limbal conjunctival papillae
Mixed VKC
what age group is associated with AKC ?
30-50 yr olds unlike VKCC 5 year old boys
what are thee seasonal association with AKC vs VKC ?
VKC is seasonal and is worse in thee spring
AKC is perineeal and worse in the winter
what other diseases are associatedd with AKC ?
history of atopic dermatitis
asthma
what are the sympttoms of AKC and VKC ?
eyelid erythema and scaling
conjunctival discharge
hyperemia and papillae
cicatrization which may lead to symblepharon
corneal keratopathy , keratoconus
what complications are more likely to happen to AKC and VKC patients ?
retinal detachement
presenile subcapsular cataract
what are the general measures for VKC and AKC ?
ABC approach
Avoid allergen
Bandage contact lens
Cool compresses
what is the medical management for VKC and AKC ?
mast cell stabilizers
topical antihistaminic
Topical NSAIDS
topical steroids
oral histamines
what is the management for unresponsive cases of AKC and VKC ?
ciclosporin
tacrolimus ointment
what surgeries can be performed for AKC and VKC ?
superficial keratectomy
surface restoration surgeries
what iss the etiology of giant papillary conjunctivitis ?
mechanically induced papillary conjunctivitis
what are thee causes of giant papillary conjunctivitis ?
contact lens wear
exposed sutures and scleral buckles
ocular prosthesis
what are the symptoms of giant papillary conjunctivitis ?
foreign body sensation
itching
redness
increased mucus production
blurring and loss of CL tolerance
symptoms may worsen after lens removal
what are the signs associated with giant papillary conjunctivitis ?
CL protein deposits may be present
mucous discharge
superior tarsal hyperemia
ptosis and tissue laxity may occur due to chronic irritation
variable size papillae up to giant
what is the treatment for Giant papillary conjunctivitis ?
removal of the stimulus
ensure effective cleaning of CL
topical drops as antihistamines , NSAID, mast cell stabilizers
what is pinguecula ?
asymptomatic elastotoic degeneration of the stroma
yellow mound found on the bulbar conjunctiva
found more on the nasal limbus rather than the temporal limbus
doesn’t grow over the cornea
what is the treatment for pinguecula ?
no treatment required
what is pterygium ?
triangular fibrovascular subepithelial growth
point of the triangle points towards the cornea
grows over the cornea
what are the differential diagnosis of pterygium ?
pseudo-pterygium
what are the parts of a pterygium ?
cap
head
body
how can you tell the difference between episcleritis and scleritis ?
episcleritis - painless, foreign body sensation ,
vessels blanch with 10% phenylpherine drops
self limiting but recurring
scleritis - very painful , exaceerbbated by eye movements andd can wake the patient up from their sleep
conjuctival vessels do not blanch on 10% phenylpherine
what is the management of episcleritis vs scleritis ?
episcleritis - avoid steroid drops, oral NSAIDs
scleritis - investigate for a systemic disease, oral NSAIDs
