Outbreak of diffuse lamellar keratitis caused by marking-pen toxicity.
OBJECTIVE
To examine the evidence that a series of cases of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) was caused by a type of marker pen.


METHODS
Eye Institute, Auckland, New Zealand.


METHODS
During a 10-week period, 522 consecutive LASIK procedures were performed using a 60 Hz IntraLase femtosecond laser (IntraLase Corp.) to create the LASIK flap and a 217Z 100 Hz excimer laser (Bausch & Lomb) to perform the refractive ablation. As standard practice, a marking pen was used to enable accurate flap realignment. Three weeks after a sudden increase in the incidence of DLK was identified, one of the 5 surgeons performed 5 consecutive bilateral cases using the marking pen in the right eyes but not in the left eyes.


RESULTS
Of the 522 LASIK cases (119 without marking pen, 403 with marking pen), DLK developed in 49 (9.4%). No eye treated without the marking pen developed DLK; of those in which the marking pen was used, 49 (12.2%) developed DLK (P<0.0001, Fischer exact test; odds ratio, 27). In the 5 consecutive bilateral cases in which the marking pen was used in the right eye but not the left eye, 4 right eyes and no left eye developed DLK (P=0.03). Forty-five of the 49 eyes with DLK quickly recovered. The other 4 developed central toxic keratopathy.


CONCLUSIONS
There is strong statistical evidence that the marking pen was a factor in the occurrence of DLK.
Eye Institute, Auckland, New Zealand. bruce@hadden.co.nz
Osmond Bruce
OB
Hadden
Charles N J
CN
McGhee
Antony Trevor
AT
Morris
Trevor Buchanan
TB
Gray
Charles Peter
CP
Ring
Adam Stewart John
AS
Watson
D004196:Disease Outbreaks; D006801:Humans; D007281:Ink; D007634:Keratitis / Q000139:chemically induced* / Q000453:epidemiology*; D020731:Keratomileusis, Laser In Situ / Q000295:instrumentation*; D054018:Lasers, Excimer / Q000627:therapeutic use; D009216:Myopia / Q000601:surgery; D009520:New Zealand / Q000453:epidemiology; D016017:Odds Ratio; D011183:Postoperative Complications; D011446:Prospective Studies; D012307:Risk Factors; D013523:Surgical Equipment / Q000009:adverse effects*; D013524:Surgical Flaps; D014792:Visual Acuity