A 34-year-old female was referred to me for a second opinion on her left eye. She had undergone an uneventful LASIK procedure to correct nearsightedness in both eyes, and was prescribed the usual postoperative medications (Flarex® [Alcon Laboratories, Fort Worth, TX] and Ocuflox® [Allergan, Irvine, CA]) four times daily, in both eyes. On the second postoperative day, the surgeon noticed some interface flap inflammation in both eyes suggestive of diffuse lamellar keratitis (DLK). The patient was started on hourly PredForte® (Allergan) drops, oral prednisone 80 mg per day, and maintained on Ocuflox® four times daily, in both eyes. Her uncorrected visual acuity (UCVA) was OD 20/25 and OS 20/30.
The patient returned 5 days later, complaining of recent onset pain in her left eye and blurred vision that began suddenly on the previous day. She was immediately referred to our service, and her exam showed UCVA OD 20/20, and OS 20/400 with a pinhole to 20/80. The cornea revealed a large, white, annular opacity in her left eye extending from the interface anteriorly to the epithelium with the greatest density located nasally. The right eye showed only trace stromal opacity in the nasal periphery. In both eyes, there was no conjunctival injection, the anterior chamber was deep and quiet, and neither corneal nor anterior chamber cells were noticed in either eye. The iris was normal and the lens was intact. Corneal topography was performed with the left eye showing extensive flattening in the midperiphery with steepening centrally to a corneal power of 60 to 70 D. The right eye showed a very small area of steepening overlying the corneal opacity.
In summary, we had a patient treated with topical and oral corticosteroids for DLK with no improvement, and actual worsening of her visual acuity 5 days after LASIK with pain noted on the sixth day.PRELIMINARY DIAGNOSIS
We made the presumptive diagnosis of intrastromal infection in the left eye, and the patient underwent a flap lift with corneal scrapings that were sent for culture for bacteria, fungus, and mycobacteria. The interface was irrigated with BSS® (Alcon Surgical, Fort Worth, TX) and topical antibiotics (tobramycin and sulfa) were placed in the flap interface. Postoperative fortified antibiotics of amikacin 25 mg/mL, vancomycin 50 mg/mL, and antifungal natamycin 50 mg/mL were empirically started every 2 hours in the left eye. The patient was instructed to discontinue the oral prednisone and decrease PredForte® to twice a day in both eyes. On the right eye, where we noticed the tiny opacity in the interface, we did not relift the flap and decided to administer the same topical antibiotics and antifungal medication every 3 hours and re-evaluate 24 hours later. On the next day, the stromal opacity was slightly better in both eyes, so we decided to simply follow both eyes with topic treatment.
One week after relifting the flap in the left eye and instituting topical therapy, the patient's UCVA was 20/25 (OD) and 20/400 (OS) with a best-corrected visual acuity (BCVA) of 20/30 (OS) with -9.00 +1.25 X 180º. The density of the stromal opacity had reduced 50% in her left eye and disappeared in the right. Two weeks later, the patient's UCVA was 20/60 (OS) and BCVA was 20/30 with -6.00 +2.00 X 167º. The steepening that showed on the first topography was now reduced in magnitude. The cornea showed a slight haze in the nasal peripheral interface (cicatricial) and no inflammatory signs. The antibiotic medication was slowly tapered, and a toric soft contact lens was fit in the patient's left eye, giving her a BCVA of 20/25.
MISSED SIGNS OF INFLAMMATION
The final laboratory results were negative, but at the time the corneal scraping was made, the patient was using antibiotic drops. Our presumptive diagnosis of infection was due to the nature of the opacity and because the condition worsened with oral and topical steroid use. The infectious process was likely accelerated by the immunosuppression. The possibility of an opportunistic infection, or an infection of insidious onset such as mycobacteria, Nocardia or fungal keratitis, led, in part, to our choice of topical agents.
The fact that the patient was using high doses of steroids (immunosuppressive dosage) explains why we could not see conjunctival injection, cells or any other signs of inflammation as we expect in infectious cases. With the inhibition of white cell migration to the site of infection, the eye is predisposed to unchallenged growth of opportunistic organisms that normally are rare and unusual sources of infection.
TAKE HEED
When the surgeon makes a presumptive diagnosis of DLK and prescribes high doses of steroids, the patient should be seen more frequently with a strict follow-up so that any signs of worsening can be noticed early. Every surgeon who performs refractive surgery must always bear in mind that infection can occur in the early postoperative period. Although it is not very frequent (infection is found to occur in the literature in 1:5000 patients, 0.02%),1 this complication is very serious and, if severe, can lead to a central scar that can be corrected only with corneal transplantation. Early corneal scraping, interface irrigation and antibiotic drops are the appropriate steps of managing this condition and important to the prognosis and visual outcome. Many surgeons are reluctant in initiating these steps in the beginning when the visual acuity is still satisfactory; however, in postponing these steps, the treatment is delayed and the result can be disastrous.
Ronald R. Krueger, MD, MSE, is the Medical Director of the Department of Refractive Surgery, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio. Dr. Krueger does not hold a financial interest in any of the materials mentioned within. He may be reached at (216) 444-8158; krueger@ccf.org
1. Gimbel HV, Anderson-Penno EE: Early postoperative complications: 24 to 48 hours, in Gimbel HV, Anderson-Penno EE (eds): LASIK Complications, Prevention and Management. Thorofare, NJ, Slack Inc., 1999, pp 81-91
