My Patient Was Splashed With Cement in Both Eyes. He Has Red, Irritated Eyes and Blurry Vision. The Exam Shows Debris on the Conjunctiva and Under the Lids, Diffuse SPK in the Right Eye, and Central Corneal Epithelial Defect in the Left Eye. What Should I Watch for?
Bennie H.
Jeng,
MD
The spectrum of chemical burns to the eye is very broad, ranging from mild epithelial disruption to severe ocular and intraocular damage. While acid burns can cause severe destruction of the ocular surface, alkali burns can be even more destructive because saponification of cell membranes can lead to rapid penetration of the alkali through the cornea and sclera into the eye, causing destruction of intraocular contents. Although the prognosis of the injured eye depends on the extent of the injury, it also depends on the rapidity of and modalities of treatment. Thus, all chemical burns to the eye, no matter how seemingly minor, must be treated immediately as the extent of ocular surface damage can be severe depending on the chemical involved.
For this particular patient, if irrigation of the eyes had not yet been performed upon arrival in the office, immediate irrigation of both eyes must be performed, even before visual acuity is checked. Manual irrigation with saline or lactated Ringer solution with a bottle or through intravenous tubing directly into the eyes as well as upper and lower fornices should be performed. If a Morgan lens setup is available, this can be used after the initial manual irrigation; otherwise, manual irrigation should be continued. Either way, copious irrigation should be done for at least 30 minutes. Topical proparacaine drops can be useful during this process. Once this irrigation is performed, one should wait a few minutes to allow equilibration, and then the pH should be tested. During the equilibration period, visual acuities can be checked and a quick slit-lamp examination can be performed to assess the ocular surface and anterior segment structures. Irrigation should then be continued until a neutral pH of 7.0 is reached.
Once the pH has been normalized, re-examination at the slit lamp should be performed, and cotton-tipped applicators or jeweler forceps should be used to remove the cement debris from the ocular surface. Special care should be taken to check in the inferior fornices and under the upper eyelid in the superior fornices (Figure 43-1). Double eversion of the upper eyelids must be performed to ensure that there is no debris in the upper fornices. It is imperative to ensure that no debris remains as any leftover debris will continue to serve as a reservoir of alkali in the form of lime, which will continue to cause damage. Any areas of frank necrosis of the ocular surface should also be noted and necrotic material should be debrided to remove any residual caustic material and to promote better epithelialization. Once all of the debris and necrosis is removed, irrigation with a few more liters of normal saline should be performed to wash out any residual alkali. Once the pH is confirmed to be normalized, irrigation can be stopped and the eyes should be re-examined once again. The epithelial defects on both the corneas and the conjunctivae should be noted (Figure 43-2) and the intraocular pressures should be checked because alkali burns can frequently cause raised intraocular pressures. The presence of intraocular inflammation should be noted and a special assessment of the limbus should be undertaken to grade the damage based on the Roper-Hall modification of the Hughes classification.1
Figure 43-1. Cement particles lodged in the upper fornix of a gentleman who suffered an alkali burn to the eye with cement. Failure to identify and remove these particles will result in a reservoir for continued alkali release onto the ocular surface. (Photo courtesy of Richard L. Abbott, MD.).
Figure 43-2. Diffuse epithelial disruption of the inferior two-thirds of the cornea after an acute alkali burn to the eye from cement. (Photo courtesy of Richard L. Abbott, MD.).
Early Medical Management
Crucial to outcome of the injury now rests with the initial medical management. Contrary to the conservative practices that are frequently employed, the use of an intensive regimen of corticosteroid eye drops is essential to a favorable outcome, and in the fact, the benefit of corticosteroid-induced reduction in inflammation from prolonged use of corticosteroids is not associated with significant corneal stromal melting.2 Thus, in this case, I would favor the use of prednisolone acetate 1% drops every 2 hours in both eyes. Along with this, I would cover with a broad-spectrum antibiotic drop such as a fourth-generation fluoroquinolone 4 times daily, and I would add a cycloplegic agent such as scopolamine 0.25% 4 times daily or atropine 1% twice daily (not phenylephrine because of its vasoconstrictive properties). Furthermore, I would consider either oral vitamin C 1 g 4 times daily (don’t forget to remind the patient to drink a lot of water) or oral doxycycline 100 mg twice daily (or both) to prevent stromal melting.3 Sodium citrate 10% drops can also be used for this purpose, but it is difficult to obtain and, in this case, is probably not necessary. If the intraocular pressure is elevated, oral acetazolamide 250 mg 4 times daily or 500 mg twice daily can be used, or a topical beta-blocker should be given. Frequent use of preservative-free artificial tears should be encouraged on an hourly basis and, if necessary, an oral analgesic can be prescribed.
Amniotic Membrane Grafting for Severe Burns
Unless a Grade IV burn is noted, surgical intervention is typically not necessary at this time. However, in severe burns, amniotic membrane grafting has become a popular modality for treatment.4 Amniotic membrane possesses nutrients and growth factors that can help suppress inflammation and promote epithelialization. In addition, it can be useful in helping to protect the fragile, damaged ocular surface. Sometimes, the placement of an amniotic membrane is done in conjunction with the placement of a temporary tarsorrhaphy. A new sutureless temporary amniotic membrane patch is also available commercially, and this may prove to be an efficient and efficacious treatment modality during the acute phase of ocular chemical burns.4
Ongoing Medical Management
During the first week, medical therapy should be continued and the patient should be seen daily until the epithelium (cornea and conjunctiva) is healed. It is common to overlook conjunctival defects, which could end up melting and necrosing. Any new areas of necrosis should be treated with debridement, and topical collagenase inhibitors such as acetylcysteine 10% can be used 4 times daily. If perforation is a threat, then a corneal or scleral patch graft (depending on the location of the necrosis) may be warranted. During this time, the intraocular pressure should be monitored and treated, and any conjunctival adhesions in the fornices (Figure 43-3) that are seen can be lysed with a cotton-tipped applicator.
Figure 43-3. Symblepharon formation in the lower fornix several weeks after an alkali burn to the eye with cement. (Photo courtesy of Richard L. Abbott, MD.).
After the first week, the topical corticosteroid drops should be tapered to 4 times daily and, if the epithelium is not healed, consideration should be made to intervene with a bandage contact lens. Aggressive lubrication should also be continued. Alternatively, pressure patching with an antibiotic/corticosteroid combination ointment in the eye is an option. If this is unsuccessful, an amniotic membrane graft with or without a temporary tarsorrhaphy may be warranted at this time. Ultimately, chronic dry eyes and limbal stem cell deficiency can be sequelae of chemical burns that may require long-term or even lifelong care. However, that being said, aggressive and prompt initial management of such cases will give the patient the best chance for a more favorable outcome.
References
1. Roper-Hall MJ. Thermal and chemical burns. Trans Ophthalmol Soc UK. 1965;85:631-653.
2. Brodovsky SC, McCarty CA, Snibson G, et al. Management of alkali burns. An 11-year retrospective review. Ophthalmology. 2000;107(10):1829-1835.
3. Wagoner MD. Chemical injuries of the eye: current concepts in pathophysiology and therapy. Surv Ophthalmol. 1997;41(4):275-313.
4. Kheirkhah A, Johnson DA, Paranjpe DR, Raju VK, Casas V, Tseng SC. Temporary sutureless amniotic membrane patch for acute alkaline burns. Arch Ophthalmol. 2008;126(8):1059-1066.