Eye patho 1 Flashcards
Blindeness of the inner eye
Chalazion patho
An acute or chronic inflammation of the eye lid secondary to blockage of one of the Meibomian or Zeis glands in the tarsal plate.
This blockage causes the stagnation of sebaceous which leads to the formation of a lesion.
Most lesions will point in the direction of the conjunctival surface causing redness and swelling.
More common in people with Blepharitis, Acne Rosacea, and Seborrheic Dermatitis.
Chalazion clinical presentation
Usually presents with a painless lump that develops in the lid or the lid margin, occasionally with mild erythema.
Presents very similar to a Hordeolum and may be difficult to differentiate between the two.
Chalazion management
Warm compress several times/day followed by massaging eyelid towards lid margin
Refer to an MO or SMA for referral to ophthalmologist if not resolved in a few days.
Hordulem stye patho
A Stye refers to an external hordeolum. It is an acute bacterial (usually Staph) infection of the follicle of an eyelash and adjacent sebaceous glands (Zeis) or sweat glands (Moll). It is commonly located at the eyelash line and has the appearance of a small pustule.
An internal hordeolum affects the meibomiam glands associated with eyelashes. The definitive difference is that it is located to the inner surface of the tarsal plate.
Hordulum clinical presentation
Other signs and symptoms besides the pustule include pain, edema, and erythema of the eyelid
Hordulum management
IAW ref (C51) warm compress with erythromycin ophthalmic ointment twice daily for 7 to 10 days.
Also Ref to Restricted acts Pharmaceuticals: table 2.
Systemic antibiotics may be required for significant surrounding cellulitis.
Refer to an MO or SMA for referral to ophthalmologist.
Learning support
Ensure to always educate your patients on infections and there implications if not treated appropriately.
Do not be shy to also educate patients on proper hand washing techniques as well as informing them to refrain from picking or attempting to ‘pop’ the pustule, this may cause further complications.
Conjuctivitis def
An inflammatory condition of the conjunctiva and is a common cause of the “red eye”.
There are many different causes but what are the 3 main causes?
Allergic, viral, bacterial
Allergic conjuctivitis
The allergen causes cross-linkage of membrane-bound IgE that causes mast cells to degranulate.
This causes a release and cascade of allergic and inflammatory mediators, such as histamine.
The most common allergen in nature to cause ocular symptoms is grass pollen.
Immunoglobulin E (Antibody) Causes Allergic Reaction
Mast Cell – A cell filled with Basophil Granules (Releases histamine during inflammatory or allergic response)
Basophil – Type of White Blood Cell
Allergic conjuctivitis symptoms
Common signs and symptoms include: watery discharge, redness, and itching.
Red and swollen eyelids.
Injected and swollen conjunctiva with papillae on the inferior conjunctival fornix .
Allergic conjuctivitis management
Remove known allergen.
Cool compress 4 times/day.
Artificial tears, topical or systemic antihistamines.
Viral conjuctivits patho
Most common cause is adenovirus however can appear as part of systemic viral infections like Mumps, Measles, and Influenza.
Must rule out Herpes Zoster and Herpes Simplex which if left untreated could cause corneal scarring and vision loss.
Often preceded by an upper respiratory tract infection.
Very contagious, good aseptic techniques and Patient education.
Most common etiology of viral conjunctivitis is adenovirus
Typical viral conjunctivitis is often preceded by an upper respiratory tract infection
Mumps: Is a viral infection that primarily affects saliva-producing (salivary) glands that are located near your ears. Mumps can cause swelling in one or both of these glands.
Measles: A highly contagious illness caused by a virus that replicates in the nose and throat of an infected child or adult. Then, when someone with measles coughs, sneezes or talks, infected droplets spray into the air, where other people can inhale them.
Incubation period of 2-14 days, can last 2-4 weeks, contagious for 2 weeks after the second eye becomes infected.
Viral conjuctivitis clinical presentation
Red eye with mild to moderate watery discharge.
There may also be Conjunctival swelling, soreness, pain, foreign body sensation, and mild photophobia.
There may also be tenderness around the preauricular node and occasionally subconjunctival hemorrhage.
Generally, one eye will be involved initially, with the other eye becoming involved within days.
Viral conjuctivitis management
Generally resolves spontaneously with only symptomatic treatment.
Cool compress, ocular decongestants, artificial tears.
Eye must be stained to rule out Herpes infection and examined with a Slit Lamp if available.
Must be referred to the MO/PA.
Bacterial Conjuctivitis patho
Typical pathogens are Staphylococcus and Streptococcus species.
Bacterial Conjuctivitis clinical presentation
Symptoms are usually painless and can affect one or both eyes.
Mucopurulent discharge which can cause adherence of the eyelids upon awakening.
Chemosis (Conjunctival edema) is common and the cornea is clear without staining.
Tenderness of the preauricular nodes is usually absent, except in Gonococcal (GC) infections.
Chemosis: Swelling (or edema) of the conjunctiva due to the oozing of exudate from abnormally permeable capillaries. It is a nonspecific sign of eye irritation. The outer surface covering appears to have fluid in it. The conjunctiva becomes swollen and gelatinous in appearance.
Gonococcal: Gonorrhea
Bacterial Conjuctivitis management
Warm compress in the morning if eyelids are stuck together.
Consider C+S (upon MO/PA request).
Antibiotic drops/ointments four times daily for 5 to 7 days.
Fluorescein stain to rule out Corneal involvement or herpes.
Aseptic technique and patient education (hand hygiene).
Avoid using contact lenses until resolved.
Refer to MO/PA.
Keratoconjunctivitis Sicca
Keratoconjunctivitis Sicca, better known as dry eyes.
The lacrimal function unit is composed of the lacrimal glands, the ocular surface (Cornea & Conjunctiva), meibomian glands, eye lids and sensory motor nerves that connect them.
This unit controls the production of the tear film and responds to environmental, endocrine, and cortical influences.
Tear film is composed of 3 layers;
1. The mucous layer: Closest to the eye, stabilizes tear film, and removes waste materials. 2. The aqueous layer: Thickest part of the tear film, hydrates the mucous layer, supplies oxygen and electrolytes to the ocular surface, and provides antibacterial defense and wound healing. 3. The lipid layer: Secreted by the meibomian glands, is the outermost layer of the tear film, slows tear evaporation, enhances tear film spreading, and provides a smooth optical surface.
Dry eyes have two classifications: Aqueous tear-deficient and evaporative.
What are some of the Occupational risk factors for ‘dry eyes’?
Answer: Prolonged visual attention to a task
Tasks that require upward gaze
Because they do not blink and or the eye surface area is more exposed
Environmental factors (such as heat, low humidity, wind, high air velocity and pollution),
Diet deficiency with low vitamin A or omega-3 fatty acid.
Medication (anticholinergic) Blocks the neurotransmitter acetylcholine in the central and the peripheral nervous system. These agents inhibit parasympathetic nerve impulses by selectively blocking the binding of the neurotransmitter acetylcholine to its receptor in nerve cells
Contact lens
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