Outer Layer: Sclera, Cornea, Pupil, and Lens Flashcards
What are features of Subconjunctival Haemorrhage?
- Completely benign
- Vessel rupture painlessly leading to red staining of cornea
- History of trauma or coughing bouts
What are features of Conjunctivitis?
- Most common eye problem
- Irritating but generally pointless
- Conjunctiva may begin to develop follicles (viral cause) or papillae (allergic or bacterial cause)
- Can be bacterial, viral, neonatal or allergic
What are the features associated with bacterial conjunctivitis?
- Purulent discharge
- Eyes get stuck together in the morning upon waking
- Conjunctiva may begin to develop papillae (allergic or bacterial cause)
What are the features associated with viral conjunctivitis?
- Serous Discharge
- There is recent Upper Respiratory Tract Infection.
- Preauricular lymph nodes are present
- Conjunctiva may begin to develop follicles (viral cause)
What are the signs and symptoms of Conjunctivitis?
- Red, itchy and inflamed eyes
- Puffy, swollen orbit and eyelids
- Discharge, especially noticeable upon waking as it builds up over night
- Photophobia indicates corneal involvement
- Conjunctival vessels will be inflamed and dilated
What are risk factors/modes of transmission for Conjunctivitis?
- Contact lenses
- Spread through contact
- Allergies (hay fever, dust allergies, fur)
What are some differential diagnosis for Conjunctivitis?
- Uveitis - more likely to be painful and will reduce visual acuity
- Glaucoma
- Early herpes zoster
- Keratitis - may follow on from conjunctivitis
- Scleritis/episcleritis
What are some investigations for Conjunctivitis?
- Swab any discharge to look for bacterial infection and culture
- If worried about other causes then do slit lamp and send for pressure testing
What are common organisms with Viral and Bacterial conjunctivitis?
- Bacterial: Staph Aureus, Strep Epidermidis, Strep Pneumoniae, H. influenzae, Chlamydia (mucopurulent discharge)
- Virus: Adenovirus, Herpes Simplex Virus
What are the features associated with allergic conjunctivitis?
- Discharge will be watery
- Does not get better with normal treatment
- Bilateral symptoms conjunctival erythema, conjunctival swelling (chemosis)
- Itch is prominent
- Eyelids may also be swollen
- History of atopy
- May be seasonal (due to pollen) or perennial (due to d
How does neonatal conjunctivitis occur?
- Passed through the birth canal
- Can be transmitted from Gonorrheal or Chlamydial infection
- Urgent samples, gram staining and swabs are needed for viral, bacterial and chlamydial infections
How is Conjucntivitis managed?
Normally a self-limiting condition that usually settles without treatment within 1-2 weeks. If it lasts further than this:
- Bacterial
- Topical antibiotic therapy such as Chloramphenicol 0.5% drops are given every 2-3 hours initially or
- Chloramphenicol ointment QDS.
- Topical fusidic acid is an alternative and should be used for pregnant women. Treatment is twice daily
- Non-bacterial
- Lubricant eye drops - ease soreness and stickiness
Contact lens should not be worn during an episode of conjunctivitis
Advice should be given not to share towels and school exclusion is not necessary
How is Allergic Conjunctivitis managed?
First-line: topical or systemic antihistamines
Second-line: topical mast-cell stabilisers, e.g. Sodium cromoglicate and nedocromil
Corticosteroids in severe allergic cases
What are causes of Corneal Abrasions?
- Damage from small objects scraping across the eye
- Foreign bodies, which may be caught under the eyelid
- Chemicals in the eye
- Infection
- Damage from UV light
What are signs of symptoms of Corneal abrasions?
- Foreign body sensation/foreign body can be seen
- Redness and watering
- Pain
- Blurred vision
- Photophobia
What are examinations for individuals with Cornal Abrasions?
- Assess depth of penetration of an injury - Refer immediately in ruptured globes
-
Full slit lamp examination
- View the cornea under blue light with fluorescein dye in the eye
- Damage will appear green under the light, ulcers may show vibrant green areas due to leukocyte build up (hypopyon). The ulcers require scraping so that gram stains and cultures can be sent
- If aqueous is seen to flow out into the laceration and is diluting the fluorescein then the globe has been ruptured (seidel’s test - ask patient not to blind after applying dye and see how fast it dilutes)
- View the cornea under blue light with fluorescein dye in the eye
- Assess visual acuity and carry out fundus examination
What are features of Recurrent Corneal Erosions?
- Erosions may continue to re-open the wounds on cornea leading to repeated episodes of burning in the eye
- During sleep, eyelid may be stuck to abrased area and upon waking may tear again as eyelid opens. Upon waking, there could be redness and photophobia with blurred vision
- Adequate lubrication is only way to reuce recurrence of symptoms
What is superficial punctate epithelial erosions?
- Small erosions which occur commonly in patients
- May be completely asymptomatic but if symptomattic then can be pain and burning sensations
- Likely to clear up once dry eyes resolve
What is the management for corneal abrasions, ulcers and erosions?
-
Chemical burns require irrigation with saline and immediate referral
- Steroids to calm the inflammation
- Debridement of necrotic tissue
- Analgesia (paracetamol and ibuprofen) for eye pain
- Remove any foreign bodies if possible
-
Prevent infection
- Prophylactic chloramphenicol eye drops
- Prophylactic levofloxacin is indicated in contact lens users as they are more likely to be infected with pseudomonas aeruginosa, which is often resistant to chloramphenicol
- Foreign bodies may require tetanus
-
Treat infected ulcers with antibiotics
- Levofloxacin and cefuroxime hourly (5 in apart so they don’t dilute each other) for 48 hours
- Give atropine as well to paralyse the ciliary body - reduces pain, improves healing and reduces risk of adhesions
What are sign and symptoms of Episcleritis?
Symptoms
- Classically not painful (in comparison to scleritis), but mild pain may be present
- Localised (sectoral or diffuse)
- Visual acuity not altered
- Watering and mild photophobia may be present
Signs
- Red Eye
- Episcleral vessels blanch with phenylephrine drops. If the eye redness improves after phenylephrine a diagnosis of episcleritis can be made
- In episcleritis, the injected vessels are mobile when gentle pressure is applied on the sclera. In scleritis, vessels are deeper, hence do not move
What are signs and symptoms of Scleritis?
Symptoms
- Watering and photophobia
- Appearance bluish-red (localised, diffuse, nodular)
- Classically painful (in comparison to episcleritis), but sometimes only mild pain/discomfort is present
Signs
- Scleral vessels appear darker and follow a radial pattern
- They are immobile and do not blanch
- Gradual decrease in vision