Eye injuries, classification and treatment. Complications of penetrating wounds of the eye. Eye burns, emergency care. Rehabilitation for burns of the eye
1. Klara Amangeldievna Rayimova
2. Kalidasan Ganesh Kumar
3. Susairaj Smith Merlin
(1. Lecturer, International Medical Faculty, Osh State University, Osh, Kyrgyz Republic
2. Student, International Medical Faculty, Osh State University, Osh, Kyrgyz Republic
3. Student, International Medical Faculty, Osh State University, Osh, Kyrgyz Republic)
Abstract and Introduction
Eye injuries can cause avoidable visual loss. Correct first aid and early referral to the ophthalmologist can help avoid most injuries. This article will discuss classification of eye injuries, initial management of penetrating injuries, complications of penetrating injuries, first aid and management of chemical burns and rehabilitation.
Ocular trauma is the most common cause of unilateral blindness in the young and middle-aged population. Males, children and those in industry, agriculture and construction are more commonly affected. The eye is small with limited protective tissues and structures like the cornea, lens, retina and optic nerve have poor regenerative ability. Small injuries can cause significant visual impairment. Management depends on the type, depth, time since injury and prevention of complications such as infection, inflammation and scarring.
Keywords: Ocular trauma, Open globe injury, Penetrating injury, Chemical burn, First aid, Rehabilitation.
Classification
Eye injuries can be classified according to cause, globe rupture and severity. It is important to use standardised terms to ensure appropriate management and prognosis.
1.Cause:
Mechanical trauma (contusion, foreign body, laceration, penetrating).
Thermal (flame, hot fluids, molten metal, steam)
Chemical (Acids, alkalis, solvents)
Radiation (UV (arc Welding/Snow blindness), Infrared, Laser)
Birmingham Eye Trauma Terminology (BETT):
The internationally recognised classification for mechanical injuries to the eye. These can be classified as a closed globe injury or an open globe injury.
Closed globe injury: No full thickness wound. Contusion are caused by blunt trauma and can lead to hyphema, lens dislocation, retinal tear or choroidal rupture. Lamellar lacerations are partial thickness wounds.
Open globe injury: Full thickness wound. Ruptures are caused by blunt trauma and cause the globe to burst at its weakest point. Penetrating injury: Single full thickness wound caused by sharp object. Perforating injury: Two full thickness wounds caused by the same object. IOFB: Foreign body within the eye. This can be classed as a penetrating injury.
2.Location:
Zone I: Cornea/Limbus. Zone II: 5mm or less behind limbus. Zone III: Beyond limbus. Wounds posteriorly will have a worse prognosis.
Severity: Ocular Trauma Score. This considers initial visual acuity, and signs including globe rupture, endophthalmitis, perforation, retinal detachment and afferent pupillary defect to predict final visual outcome.
Eyelid and Orbital injuries: Injury to eyelid/canalliculi (laceration) and orbital wall fractures (blow out fractures) are classified separately and require plastic/maxillofacial involvement.
General Principles
All eye injuries will be assessed the same way. Life threatening injuries should be addressed first. Patient history, visual acuity and eye examination should be performed. Visual acuity will be assessed first but if chemical injury is suspected irrigation should be performed.
History:
Time of injury, cause (metal on metal, wood, glass, chemical), were there any protective measures, tetanus status.
Examination:
Visual acuity, pupil shape and response, eye motility, eyelids, conjunctiva, cornea (fluorescein), anterior chamber, lens and fundus if possible. Slit lamp if available. Imaging should be CT scan of orbit. Avoid MRI if there is a chance of a metal foreign body.
General First Aid:
Do not apply pressure, rubbing or attempt to remove foreign body.
Do not irrigate penetrating injuries.
Cover with protective hard shield. Paper cup can be used in an emergency.
Ensure patient is laid down with head elevated. Do not eat or drink in case of surgery.
Avoid vomiting, straining. Give anti-emetics if possible. Analgesia.
Urgent referral to ophthalmology.
Penetrating injuries and complications
Penetrating injuries are full thickness wounds to the cornea or sclera. This is an ophthalmological emergency as the globe is at risk of infection and intraocular contents may prolapse.
Signs:
Shallow anterior chamber, irregular pupil, intraocular contents prolapsing, positive Seidel’s test (leakage of aqueous humour when using fluorescein), low intraocular pressure (hypotony), hyphema. Some injuries can be small with subtle findings. If there is any history of high velocity trauma (hammering, grinding, explosion) thorough search for foreign body should be performed.
Management:
Emergent surgery. Suture wound. Ideally should be closed within 24 hours. Re-position or excise uveal tissue that has prolapsed depending on viability.
Foreign body removal. Often removed using magnet or forceps. Posterior foreign bodies are often removed with vitrectomy.
Broad spectrum antibiotics. Risk of endophthalmitis is high so topical and systemic antibiotics should be given. In high risk wounds (soil/organic foreign body) intraocular antibiotics will be used.
Tetanus. Anti-inflammatory.
Secondary surgery. Removal of lens, vitrectomy and retinal repair may be required. Usually done within days/weeks.
Complications:
Endophthalmitis. Infection of the eye by bacteria or fungi. This is a feared complication as the patient will suffer pain, hypopyon and rapid visual loss. Urgent intraocular antibiotics will be required. Often vitrectomy will be needed.
Traumatic cataract. Damage to lens capsule causing swelling and opacity. Traumatic uveitis and hyphema will occur as there is inflammation within the globe. This can cause raised pressures. Secondary glaucoma will occur due to obstruction from blood, inflammation, lens and scarring.
Retinal detachment and proliferative vitreoretinopathy. Scar tissue pulls on retina. Usually occurs weeks after injury. Can be a major cause of poor visual recovery. Sympathetic ophthalmia. Rare complication of penetrating trauma. Autoimmune reaction in the uninjured eye. Can occur anywhere from days to years after injury. Traditionally eye removal would be done early if it was hopelessly damaged to prevent this complication. However now the main treatment is steroid and immunosuppressant medication.
Siderosis and chalcosis. Toxic effect on retina/lens from retained iron/copper foreign bodies. Scarring will occur in cornea causing astigmatism. Phthisis bulbi can occur due to eye shrinking and losing function due to severe trauma.
Outcome will depend on initial visual acuity, size of wound, location of wound, retinal and lens damage and time since injury. Small anterior wounds often have useful vision due to early treatment. Posterior wounds with retinal damage often will not.
Chemical burns and emergency treatment
Chemical burns are the most urgent of eye injuries. Outcome depends on initial treatment in the first few minutes. Treatment should start whilst assessing. Thermal and radiation burns will usually be less severe but still should be assessed.
Types:
Chemical. Alkaline substances (lime, ammonia, caustic soda, cement) are more dangerous due to penetrating deeper into cornea and causing damage to inside of eye. Acids often form a protein coagulation layer preventing spread. Strong acids (hydrofluoric acid) can penetrate deep.
Thermal. Flame, hot metal, steam or hot liquid. Usually covered by eyelids so eyelid burns are common.
Radiation. Arc welding and strong UV light can cause photokeratitis. This can cause severe pain several hours later.
Emergency Treatment:
Irrigate immediately. Use nearest clean water/saline. Irrigate for at least 15-30 mins. Ensure eyelids are open and patient is looking in all directions. Do not wait for neutralisers or transport arrangements.
Remove contact lenses and solid material.
Continue to irrigate in theatre using saline/Ringers. Continue until pH of conjunctival sac is neutral (around 7.0-7.4). Check with litmus paper. Once irrigation has finished check again after around 5-10mins as chemical can become trapped in tissues causing changes in pH.
Evert upper lid and wipe fornices to remove material (e.g. lime).
Give analgesia. Topical antibiotic. Cycloplegic drops to relieve spasms. Reduce pressure if increased.
Perform fluorescein exam. Check pressure. Refer to ophthalmologist.
Severity:
Severity will depend on how cloudy the cornea is and how much blanching there is to the limbus (stem cells of cornea). Roper-Hall classification uses these two factors to classify 4 different severities. Dua classification splits this further depending on amount of limbus affected (in clock hours) and % of conjunctiva affected.
Mild. Damage to corneal epithelium and minimal/no ischaemia to limbus. Good prognosis. Usually heals within days. Moderate. Hazy cornea and minimal ischaemia. Fair prognosis. Can take longer to heal. Severe. Severe corneal opacification and severe ischaemia to limbus. Poor prognosis. Risk of corneal melt, perforation and scarring.
Treat with lubricant, preservative free artificial tears, topical antibiotics and steroids (only in early stages. Should be carefully tapered after around 7-10 days as can cause corneal melt with prolonged use). Give ascorbate and citrate to help healing. Pressure reducing drops. Surgery required for severe burns. Amniotic membrane transplant, symblepharon rings or lysis. Limbal stem cell transplant. Later keratoplasty (cornea graft) or keratoprosthesis.
Complications:
Epithelial defects, corneal ulceration/perforation, symblepharon, dry eye, limbal stem cell deficiency (conjunctivalisation), corneal vascularisation, cataract, secondary glaucoma and permanent corneal opacification.
Thermal and Radiation:
Cool with clean water. Do not apply ointment or force open swollen eyelids. Cover loosely with non-adherent dressing. Refer. Photokeratitis: Cold compresses, lubricant, cycloplegic and oral analgesia. Usually resolves in 1-2 days.
Rehabilitation begins in the acute phase and can continue for months/years as burns take time to heal and scarring can occur. Aim to protect surface, improve vision as much as possible, prevent complications and get patient back to work.
Medical/Surgical:
Early (1st week): Control pain and inflammation. Epithelium healed. Prevent infection. Regular pressure monitoring.
Reconstructive (Weeks 1-3): Lubricate eye. Prevent eyelid adhesion. Regular follow up of cornea.
Late (Approx. 3 weeks onwards): Scarring, dry eye and limbal stem cell failure. Reconstructive surgery will usually be planned once eye has settled and no inflammation for several months.
Visual/Optical:
Spectacles. Rigid gas permeable/scleral contact lenses to flatten irregular scarred cornea. Cornea graft or keratoprosthesis for severe scarring. Later procedures such as cataract surgery. Low vision aids (magnifiers, high contrast, screen readers, good light).
Orientation/mobility. Monocular patients will need to use their better eye.
Surface/eyelid:
Preservative free lubricants long term. Punctual plugs for severe dry eye. Serum drops if available. Surgery for eyelid abnormalities (ectropion/symblepharon). Educate patient not to rub eye. Protective glasses. Educate patient on symptoms that need prompt review (redness, pain, discharge, sudden vision loss).
Psychological/Social:
Losing vision and having facial scarring can cause anxiety, depression and social withdrawal. Counselling, peer support and cosmetic treatments (prosthetic/scleral shell for blind disfigured eye). Vocational advice. Adapt to work. Children will need support with school and visual development especially if injured at an age where amblyopia could occur.
Follow Up:
Regular follow up is very important. Pressure, cornea and fellow eye should be assessed. Plan further surgery. Usually a team will be involved including an ophthalmologist, nurse, optometrist, low vision therapist and psychologist/social worker if required.
Prevention:
Most serious eye injuries can be prevented. Safety goggles/glasses should be worn when grinding/hammering/welding and using chemicals. Face shield if splashing likely. Eye washing stations should be available in workplaces using chemicals. Supervise children when playing with toys/fireworks/sharp objects. Avoid exposing eyes without protection during sports. Label and store household chemicals safely (especially cleaning products/lime based) to reduce injuries.
Conclusion:
Eye injuries can range from mild surface abrasions to severe open globe injuries and chemical burns. Accurate classification is important. Penetrating injuries require protection using a shield, no pressure and urgent surgery to close wound with antibiotic cover. Chemical burns require immediate prolonged irrigation. Threats after injury are infection, scarring, increased pressure and retinal detachment. Rehabilitation should focus on the eye, vision and overall well-being. Most efficient way to preserve vision is prompt first aid and early referral.
References:
1. Standard references for this topic. References listed from memory please check in library/database. Please follow referencing style for your course.
2. Kuhn F, Morris R, Witherspoon CD, Mester V (2004) The Birmingham Eye Trauma Terminology system (BETT). Journal Francais d'Ophtalmologie.
3. Kuhn F, Maisiak R, Mann L et al (2002) The Ocular Trauma Score (OTS). Ophthalmology Clinics of North America.
4. Roper-Hall MJ (1965) Thermal and chemical burns of the eye. Transactions of the Ophthalmological Societies of the United Kingdom.
5. Dua HS, King AJ, Joseph A (2001) A new classification of ocular surface burns. British Journal of Ophthalmology.
6. American Academy of Ophthalmology (2015) Basic and Clinical Science Course. Section 8: External Disease and Cornea. Section 12: Retina and Vitreous.
7. Kanski JJ, Bowling B (2011) Clinical Ophthalmology: A Systematic Approach. Elsevier.