Beware of acute corneal oedema after SLT in selected patients

The Science behind the Tip

The increase in the practice of selective laser trabeculoplasty (SLT) has brought attention to rare side effects such as acute corneal oedema without associated intraocular pressure (IOP) spike. Very few cases have been documented, therefore it is difficult to establish potential associations. Most of the reported cases present as a complication within the first day to a week post-SLT (1- 5). The cases documented so far involved caucasian woman of medium age with myopic eyes. (1,4,5). Long-term steroid therapy usually resolves most cases, but residual subepithelial scarring may persist as well as corneal thinning evidenced by pachymetry (4,5). This corneal thinning seems to coexist with a flattening that results in an early hyperopic shift (1,4,5). It tends to revert to pre-laser values over subsequent months, even though central haze might remain (1). The mechanism behind this phenomenon remains unknown. The proposed hypotheses include suspected HSV reactivation (4), pre-existing corneal ectasia (1), abnormal corneal tissue response to inflammatory mediators released after SLT (1,3,4) or direct laser impact on the cornea (1).

References

1. Loyola Arancibia AE, Corrêa Gontijo VA, Bassoli Scoralick AL, Kanadani FN, Prata TS. Partial corneal recovery following selective trabeculoplasty-induced keratopathy: Longitudinal analysis through scheimpflug imaging. Am J Ophthalmol Case Rep. 2021;22:101062. Published 2021 Feb 26. doi:10.1016/j.ajoc.2021.101062
2. Ozkok A, Tamcelik N, Ucar Comlekoglu D, Iskeleli G. Corneal decompensa-on aOer selective laser trabeculoplasty. Case Rep Ophthalmol Med. 2014;2014:851971. doi:10.1155/2014/851971
3. Knickelbein JE, Singh A, Flowers BE, et al. Acute corneal edema with subsequent thinning and hyperopic shiO following selective laser trabeculoplasty. J Cataract Refract Surg. 2014;40(10):1731-1735. doi:10.1016/j.jcrs.2014.08.002
4. M. Regina, V. Y. Bunya, S. E. Orlin, and H. Ansari, “Corneal edema and haze after selective laser trabeculoplasty,” Journal of Glaucoma, vol. 20, no. 5, pp. 327–329, 2011.
5. Song J, Yu D, Song A, et al. Corneal thinning and opacity following selective laser trabeculoplasty: a case report. Br J Med Med Res. 2014;4:279–287

Contributors: *Luisa Castro-Roger MD MSc, Liverpool, United Kingdom

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