Ocular Burns

The blink reflex usually causes the eye to close in response to a thermal stimulus. Thus, thermal burns tend to affect the eyelid rather than the conjunctiva or cornea. Eyelid burns should be cleansed thoroughly with sterile isotonic saline solution followed by application of an ophthalmic antimicrobial ointment (eg, bacitracin twice a day). Severe burns may require multiple surgical interventions, including skin grafting. If the thermal burns to the eyelid are severe, lid retraction, lagophthalmos (inability to close the eyelids), and corneal exposure may result. This may require temporary closure of the eyelids with a suture tarsorrhaphy and delayed reconstructive repair.

Most thermal burns affecting the conjunctiva or cornea are mild and heal without significant sequelae. They are treated with oral analgesics (acetaminophen with or without oxycodone), cycloplegic mydriatics (eg, homatropine 5% 4 times a day), and topical ophthalmic antibiotics (eg, bacitracin/polymyxin B ointment or ciprofloxacin 0.3% ointment 4 times a day for 3 to 5 days) (1).

Chemical burns of the cornea and conjunctiva represent 11 to 22% of ocular trauma and can be serious, particularly when strong acid or alkali is involved (2). Alkali burns cause liquefaction necrosis, whereas acid burns cause coagulation necrosis; alkali burns have deeper penetration and tend to be more serious than acid burns.

Ocular Burn (Chemical)

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Chemical burns should be irrigated copiously as soon as possible. The eye may be anesthetized with 1 drop of proparacaine 0.5%, but irrigation should not be delayed and should last for at least 30 minutes. Any irrigation solution (eg, saline solution or sterile water) or even tap water is adequate and should be started without delay after exposure. A hypertonic solution, such as borate buffer solution, may be more effective at correcting ocular surface pH than other commonly used irrigating solutions, while a balanced saline solution (a sterile, isotonic solution with a pH of 7.4) is better tolerated by patients allowing for longer irrigation time. Irrigation may be facilitated by using an irrigating lens placed under the lids, although this can be more irritating to some patients than irrigation without such a lens. In acid and alkali burns, some experts suggest at least a 30-minute initial irrigation with 1 to 2 L of either saline solution or sterile water; most experts recommend irrigation until the pH of the conjunctiva is in the normal range of 7.0 to 7.2 (using expanded pH paper).

How To Irrigate the Eye

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After irrigation, the conjunctival fornices should be examined for chemical embedded in the tissue and swept with a swab to remove trapped particles. The superior fornices are exposed by using double eyelid eversion (ie, first everting the eyelid and then inserting a swab under the everted eyelid and lifting it up until the fornix is visible).

Mild chemical burns are generally treated with topical ocular antibiotics (eg, erythromycin ointment 0.5%) 4 times a day and cycloplegia if needed for comfort (eg, cyclopentolate). Because topical corticosteroids can cause corneal perforation after chemical burns, they should be given only by an ophthalmologist (3). Topical anesthetics should be avoided after initial irrigation; significant pain may be treated with acetaminophen with or without oxycodone. If the patient's renal function is not impaired, oral vitamin C (2 g 4 times a day in adults) can be used to help with collagen synthesis. Oral doxycycline can also be used in appropriate patients to stabilize collagen, but both of these practices should be done in consultation with an ophthalmologist (4). Citrate eye drops, to decrease proteolytic activity, and platelet-rich plasma eye drops may also aid in healing and should be given only in consultation with an ophthalmologist (5).

Severe chemical burns require treatment by an ophthalmologist to save vision and prevent complications such as corneal and/or conjunctival scarring, perforation of the globe, and lid deformities; severe chemical burns may require surgical procedures in addition to medical treatments. Patients with severe decreased vision, avascular areas of conjunctiva, or loss of conjunctival or corneal epithelium as demonstrated by fluorescein staining should be examined by an ophthalmologist as soon as possible and no longer than 24 hours after the exposure.

Chemical iritis is suspected in patients with photophobia (deep eye pain with exposure to light) that develops hours or days after a chemical burn and is diagnosed by finding flare and white blood cells in the anterior chamber during slit-lamp examination. Chemical iritis is treated by instilling a long-acting cycloplegic (eg, a single dose of homatropine 2% or 5% or scopolamine 0.25% solution).

1. 1. Malhotra R, Sheikh I, Dheansa B: The management of eyelid burns. Surv Ophthalmol 54(3):356-371, 2009. doi: 10.1016/j.survophthal.2009.02.009

2. 2. Clare G, Suleman H, Bunce C, Dua H: Amniotic membrane transplantation for acute ocular burns. Cochrane Database Syst Rev 2012(9):CD009379, 2012. doi: 10.1002/14651858.CD009379.pub2. Update in: Cochrane Database Syst Rev 9:CD009379, 2022. doi: 10.1002/14651858.CD009379.pub3

3. 3. Dohlman CH, Cade F, Pfister R: Chemical burns to the eye: paradigm shifts in treatment. Cornea 30(6):613-614, 2011. doi: 10.1097/ICO.0b013e3182012a4f

4. 4. Smith VA, Cook SD: Doxycycline-a role in ocular surface repair. Br J Ophthalmol 88(5):619-625, 2004. doi: 10.1136/bjo.2003.025551

5. 5. Pfister RR, Haddox JL, Yuille-Barr D: The combined effect of citrate/ascorbate treatment in alkali-injured rabbit eyes. Cornea 10(2):100-104, 1991. doi: 10.1097/00003226-199103000-00002.