management of blepharitis and dry eye disease

Cards (36)

  • Anterior Blepharitis
    • Crusty appearance - a more streptococcal reaction
    • Sticky/oily appearance - the more seborrheic subgroup reaction
    • White circular oily caps - capped meibomian glands
  • Staphylococcal blepharitis
    • Caused by: Direct infection
    • Reaction to staphylococcal exotoxin
    • Allergic response to staphylococcal antigen
  • Seborrheic blepharitis
    Disorder of the ciliary sebaceous glands of Zies
  • Demodex
    Small mites
  • MGD/Posterior Blepharitis
    • Opaque nature to the meibomian glands and they leak
    • Should not be thick and opaque
    • The gap in the middle, the atrophy occurs when it is chronic. The meibomian gland death
  • Order of Management
    1. Hot compresses
    2. Lid massage
    3. Lid hygiene
    4. Dry eye management - if necessary
  • Hot compresses
    • Softening anterior blepharitis crusts (better if wet)
    • Liquefy or soften the contents of obstructed glands (better if dry)
    • ≥40°C is required for approximately 5 minutes
    • Mixed evidence on moist versus dry heat
  • Warm cloth
    • Wet facecloth either with warm tap water or popped in the microwave to heat up
    • Multiple cloths can be wrapped around each other to retain heat (known as bundling)
    • Caution with too high a temperature
    • >45°C can cause a thermal burn and corneal deformation on eye rubbing
    • 5 minutes up to twice a day
    • Most cost efficient
  • Commercial eye masks
    • More convenient because they are designed for the task
    • Usually go in the microwave or activated with pressure if single use
    • Beads (absorb the heat and then gradually release it over 5-10 mins)
    • Natural grains
    • Hot or cold depending on the use
    • Antibacterial coating on the mask to keep it sterile
    • Removable covers that can be washed
  • Massage
    • Not enough just to heat the meibomian glands
    • Removing the obstruction that is now hopefully softened
    • This should allow the normal oils to flow
    • Needs to be done regularly
    • Firm pressure with the fingertips below the lower eyelashes and above the upper
    • Should not be painful
  • Lid hygiene
    • Physical removal of debris from the eyelashes
    • Removes bacteria
    • Various options - water, gels, wipes
    • Mixed literature for which method is best
  • Lid hygiene is widely considered an effective mainstream therapy for MGD and blepharitis
  • Despite the fact that various professional organisations suggest ways to clean the eyelids, to date, there are no universally accepted guidelines for lid cleansing and peer-reviewed evidence for such advice is lacking
  • Water
    • Cool boiled water - don't risk burning but sterile
    • With added baby shampoo
    • With added bicarbonate of soda
    • Important to use clean cotton bud/pad dipped in the solution
  • Baby shampoo
    • Ration of 10:1, cooled boiled water to baby shampoo
    • Literature shows an improvement in symptoms, crusting and lash loss
    • But worsening in MG capping and possible reduction in goblet cell function
  • Bicarbonate of soda
    • Gentle abrasive
    • Mechanical removal of crusts
    • ¼ teaspoon mixed with cooled boiled water
  • Pre-prepared solutions
    • Saves mixing solutions at home
    • More expensive
    • Use alongside cotton pad
    • Ingredients - Blephasol (micelle solution, preservative free)
    • OcuSoft (foam cleanser, contains preservative)
  • Lid wipes
    • Most expensive option
    • Easiest option
    • Single use wipes
    • The main point with lid hygiene is the mechanical action, rather than the agent used
  • Antibiotics
    • Staphylococcal and seborrheic blepharitis can be managed with a short course of topical antibiotics
    • Lid hygiene should continue after completion of the course
  • Chloramphenicol
    • 1% chloramphenicol ointment
    • Rubbed into the eyelid margin twice a day for 1 week (dosage and duration can vary, check local guidelines)
    • Broad spectrum
    • Bacteriostatic by inhibiting protein synthesis
    • No contact lens wear during treatment, safety in pregnancy has not been established, not for use when breast-feeding
    • Can cause transient blurring and stinging
  • Dry eye disease management
    • Wide range of symptoms - lacrimation, discomfort, burning, itching
    • Signs - reduced tear production, reduce tear stability
    • Includes managing anterior blepharitis/MGD as appropriate
    • Tear substitutes - replacing the component that is lost (drops, gels, ointments)
  • Retention time
    • The longer the retention time the better as that will relieve symptoms for longer
    • But to achieve a longer retention time usually involves a higher viscosity which can have issues
  • Viscosity
    • The quality or state of being viscous (= thick and sticky and not flowing easily)
    • Corresponds to the concept of 'thickness'
    • If an eye drop has a low viscosity, it will be washed away very quickly e.g. saline
  • Viscosity-enhancers
    • Increasing tear film thickness
    • Protecting against corneal/conjunctival desiccation
    • Improving goblet cell density
    • And therefore, improving patient symptoms
  • Low viscosity
    • Easy to instil
    • Doesn't blur vision
    • Shorter retention time
    • Needs frequent use to keep symptoms at bay
  • High viscosity
    • Long retention time
    • Perfect for overnight use
    • Can be trickier to instil
    • Can blur vision
    • Debris can gather on lashes and eyelids
    • Reduced compliance and patient satisfaction
  • Viscosity enhancers in eye drops
    • Carboxymethyl cellulose (CMC)
    • Hyaluronic acid (HA)
    • HP-guar
    • Hydroxypropyl methylcellulose (HPMC) aka Hypromellose
    • Polyvinyl alcohol (PVA)
    • Polyethylene glycol
  • Lipids in eye drops for MGD
    • Castor oil
    • Mineral oil
    • Soybean oil
    • Sea buckthorn seed oil
    • Liposomal spray
  • Ingredients in gels
    • Carbomer 940
    • Carboxymethylcellulose (higher concentration)
  • Ingredients in ointments
    • Liquid paraffin
    • Wool fat (lanolin)
    • White soft paraffin
    • Mineral oil
  • There is no evidence that one eye drop is better than the other
  • Although there are scores of formulations and products available, which vary by geographic region, there does not appear to be any substantial difference in effectiveness among them
  • Preservatives
    • Prevents microbial growth in the bottle
    • Maintains the sterility of the solution once opened
    • Cheaper than single dose vials
  • Detergent preservatives
    • Benzalkonium chloride (BAK)
    • Polyquaternium-1 (Polyquad)
    • Ruptures the outer membrane of the micro-organism
    • BAK was traditionally used but has been shown to be toxic to the ocular surface
    • Polyquad is derived from BAK and is considered less toxic, as while it is attracted to bacteria it is rejected by corneal epithelial cells
  • Oxidation preservatives
    • Sodium chlorite (Purite)
    • Sodium perborate (GenAqua)
    • Alters the lipid membrane of the microbes
    • Reduced toxicity to ocular surface
    • Able to keep concentrations low to avoid toxicity
  • Complications of preservatives
    • Long term use of a preserved drop can lead to Conjunctivitis Medicamentosa
    • Symptoms - irritation, stinging, burning, photophobia, ocular redness, blurred vision, lid swelling
    • Signs - usually diffuse punctate staining of cornea/conjunctiva, tear film instability
    • Switching the patient to a preservative free drop should lead to a resolution of the problem
    • Cold compresses can also improve symptoms
    • Avoid the preservative in the future
    • Need to weigh up the benefits versus the complications