Purchase this article with an account.
Andrea Petznick, Lei Zhou, Roger Beuerman, Siew Kwan Koh, Louis Tong, Jodhbir Mehta; Inflammatory and lacrimal gland proteins in the tear film after femtosecond LASIK. Invest. Ophthalmol. Vis. Sci. 2013;54(15):3116.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Dry eye is a major side effect of LASIK. It has not been clear if these complaints are caused by inflammatory changes or regenerative corneal nerve changes. A proteomics study of tears was carried out with patients who underwent femtosecond LASIK to address two questions: 1) Is LASIK-associated dry eye a result of inflammation? 2) Does the newer femtosecond platform VisuMax using smaller flap, higher repetition rate, lower laser pulse energy and different corneal suction reduce adverse ocular surface changes?
In a prospective contra-lateral paired eye study, corneal flaps of 22 patients were created by either the VisuMax or IntraLase laser. Tear samples were collected before surgery, and at 1 week and 3 months postoperatively using Schirmer’s strips. A panel of dry eye protein markers were analyzed using iTRAQ (isobaric tagging for relative and absolute quantitation) mass spectrometry. Tear protein ratios were calculated relative to preoperative protein levels at baseline.
There was little change in the inflammatory ocular surface condition, but lacrimal gland secretions were affected. The pro-inflammatory associated protein S100A9 was downregulated while α-1-acid glycoprotein 1 (ORM1) was upregulated in IntraLase at 1 week postoperatively. The lacrimal gland proteins, lipocalin-1 and lysozyme showed lower ratios in IntraLase and VisuMax, while prolactin-inducible protein (PIP) and lactoferrin were dowregulated only in IntraLase at 1 week postoperatively. Downregulation of lipocalin-1, PIP and lactoferrin was observed in IntraLase 3 months after surgery. A comparison between lasers showed that IntraLase affected protein ratios significantly more. At 1 week postoperatively, α-enolase (ENO1) ratio was greater in IntraLase as compared to VisuMax (1.324 vs. 0.940, p<0.04). At 3 months postoperatively, IntraLase displayed significantly lower ratios than VisuMax for lipocalin-1 (0.590 vs. 0.944), lactoferrin (0.605 vs. 1.069) and lysozyme (0.684 vs. 1.007) (p<0.05).
The changes in lacrimal gland proteins suggest that the Functional Unit controlling tear secretion is affected by LASIK, which certainly leads to a decrease in neural function. The sensations of corneal irritation or “dry like sensations” following surgery are likely to be related to regenerative changes in the corneal nerves. Technological advancements of VisuMax appear to be beneficial for the ocular surface.
This PDF is available to Subscribers Only