anterior segment trauma 1

What is the eye protected by?

Lids, eyelashes and margins of orbit

4 ways the eye can be injured

1. Chemicals

2. Heat

3. Radiation

4. Mechanical trauma

Closed globe

No full-thickness wound of eye wall but there is intraocular damage

Open globe

Full thickness injury of eye wall and intraocular structures

Contusion

Results of direct energy delivery to the eye, by a blunt object

Rupture

Full thickness wound of the eyeball, caused by a blunt caused by a blunt object

Lamellar laceration

Partial thickness wound of the eye wall

Laceration

Full thickness wound of the eye wall by a sharp object

Penetrating injury

An injury where a foreign object has been embedded in the eye.

Perforating injury

Full thickness injury, with both entry and exit wound

Haematoma (black eye)

• due to blunt trauma causing black lid or forehead

• Usually innocuous (not harmful)

Caution of:

1. Trauma to globe or orbit - associated blunt trauma injuries

2. Orbital roof fracture - black eye + SCH w/o posterior limit

3. Basal skull fracture - bilateral “ring” haematomas (panda eyes)

Eyelid lacerations

Very common can be:

1. Superficial lacerations

2. Lid margin lacerations

3. Lacerations w mild tissue loss

4. Lacerations w extensive tissue loss

5. Canalicular lacerations

Possibility of globe trauma (penetrating injury, conjunctival or scleral laceration)

Eyelid lacerations treatment:

1. Need surgical repair

2. Protective eye shield and immediate emergency

Subconjunctival haemorrhage

Often spontaneous from coughing, sneezing, vomiting + heavy lifting, or increasing intrathoracic pressure.

• Frequent SCH indicates systemic hypertensions, diabetes, anticoagulant therapy

• Dense SCH = obscure damage to globe

If spontaneous then resolves in few days or weeks, can give px lubricants.

Why do we ensure to see posterior limits of SCH

Being able to see posterior limits of the haemorrhage in all cases is a really good sign.

Otherwise may be associated to orbital fractures

How do corneal abrasions occur?

Due to epithelium abraded by foreign object which can be fingernails, paper, eye rubbing, thrown objects etc.

What are the symptoms + signs of corneal abrasions? (5)

1. Intense pain

2. Photophobia

3. Redness

4. Watering

5. Staining with fluorescein

Why do we need to measure the size of the corneal abrasion

• need to assess/measure/record size of epithelial defect as larger abrasions may be from anterior chamber reactions.

Why and how do we need to differentiate between a corneal abrasion and HSV dendrite?

Healing of epithelial defect may resemble herpes simplex virus dendrite hence to differentiate is the measure corneal sensitivity.

Normal corneal sensitivity = corneal abrasion.

Why is it important to know the history of a corneal abrasion?

1. Recurrent may be epithelial basement membrane dystrophy

2. Organic material (in farmer’s) = fungal infection risk

3. High speed FB = penetration/perforating risk

4. Track staining where retained FB is under upper lid. (Can evert lid or sweep forniches if can’t evert due to pain)

What are the treatments for corneal abrasions? (6)

1. Broad spectrum antibiotic if not FB

2. Non preserved lubricants until healed

3. Daily review

4. If there is loose epithelium then debride with a cotton bud to speed up healing

5. Do not patch eye as it doesn’t speed healing esp in CL abrasion or from organic material.

6. Manage anterior chamber reactions if present with cycloplegia drops

Ocular surface FB

• are often repeat injuries which most aren’t associated with ocular morbidity

• Check for perforating injury

• May have conjunctival or corneal FB

• Most commonly from higher risk activity w/o protective eyewear

What are the signs and symptoms of corneal FB?(10)

1. Pain and FB sensation

2. Photophobia

3. Redness and watery eyes

4. Conjunctival hyperaemia and chemo sis

5. Possible anterior chamber reaction

6. Reduced VA

7. Asymmetrical IOP

8. Shallow anterior chamber

9. Lens capsule defect, opacity

10. Assess iris for transillumination

Management of posterior corneal FB:

1. If FB in posterior stroma = perform Seidel test before and after removal

• if see waterfall effect = complete perforation hence px needs to go to hospital

Superficial corneal FB removal

• Remove with 25-bent gauge needle with flattened upturned tip and instil topical antibiotic cover after.

• 24hr review after removal

• Remind px to wear safety glasses

Corneal lacerations

Shallow lacerations = corneal abrasion

• larger lacerations need surgical repair sometimes with cyanoacrylate glue or suturing

• Optom management = eye protection and referral.

Photokeratopathy (“welder’s flash”, “Snow blindness”, “Arc eye”)

An UV burn often as welding arc is struck.

Symptoms and signs of photokeratopathy

1. Highly painful

2. Tearing, photophobia, redness, lid and conjunctival swelling

Treatment of photokeratopathy

Usually heals within 2-3 days

• non preserved lubricants, ice packs and sunglasses

• Advise on proper eye protection

• antibiotics are usually not required unless there is large epithelial sloughing

What are the types of chemical trauma?

1. Acids

2. Alkalis which penetrate the eye more and 2x more common than acids.

What do alkalis (chemical trauma) cause?

1. Significantly higher ocular morbidity

2. Saponify cell membranes

3. Denature collagen

4. Thromboses vessels

What do acids (chemical trauma) cause?

• Cause precipitation and coagulate protein

• prevent further penetration through cornea

• Binds to epithelial surface

What are examples of acids?

1. Sulfuric (car batteries)n

2. Hydrochloric (swimming pool)

3. Concrete cleaners

4. Acetic acid

5. Hydrofluoric (glass etching)

What are some examples of alkalis?

1. Ammonia, ammonia hydroxide

2. Sodium hydroxide

3. Calcium hydroxide

Others = shampoos, facial cleansers - resolve much quicker

What signs and symptoms do patients with serious chemical trauma present?

1. Necrosis of conjunctiva and cornea epithelial cells

2. Disruption and occlusion of limbal vasculature = lose of limbal cells

3. Potential for:

• conjunctivalisation and vascularisation of cornea

• Persistent epithelial defect

• Cicatricial entropion symblep

4. Cause iris and lens damage if penetrates to anterior chamber lending to glaucoma

5. Deeper penetration causes stromal opacification

What are the managements of chemical trauma?

1. Immediate first aid

2. Irrigation

3. Instil local anaesthetic

4. Sterile saline, Eyestream and tap water

5. 15 mins minimum but 30 mins better

6. For severe burns - continue irrigation til attend emergency

What are further managements for chemical trauma?

After irrigating, treatment depends on severity which is graded by the Roper-Hall classification.

Four grades.

Managment of chemical injury - grade 1 + 2

1. Prophylactic antibiotic

2. Cycloplegic for ciliary spasm if AC reaction

3. Topical steroids qid - reduces collagen synthesis and inhibit fibroblast migration, affects stromal repair

Management of more severe chemical burns

1. High dose vitamin C

2. 10% sodium ascorbate q2h topically - promotes healing by promoting collagen synthesis by fibroblasts

3. 10% sodium citrate q2h topically

4. Tetracyclines - inhibit collagen are and may reduce risk perforation.