- Journal of Refractive Surgery
- May 2011 - Volume 27 · Issue 5: 356-363
To illustrate the hypothesis that epithelial thickness profile maps could be a useful adjunct to topography in monitoring patients after corneal collagen cross-linking (CXL) treatment.
Epithelial thickness profile in vivo was measured by Artemis very high-frequency (VHF) digital ultrasound scanning (ArcScan Inc) across the central 10-mm corneal diameter of a patient before collagen CXL for corneal ectasia after LASIK and at intervals up to 2 years later. Manifest refraction, corneal topography, and corneal front-surface aberrations were also monitored. Epithelial thickness changes were cross-correlated with corneal topography changes and corneal front-surface aberration changes.
Corneal collagen CXL appeared effective in halting the progression of corneal ectasia. Manifest refraction showed a reduction in spherical equivalent over time after CXL in both eyes. Corneal topography demonstrated stable central keratometry in both eyes. Corneal wavefront aberrations demonstrated a reduction of higher order root-mean-square coma and spherical aberration in both eyes. The epithelial thickness profile was altered, with a slight reduction of the area of epithelial thinning and decreased peripheral thickening. This resulted in minimizing the difference between the thinnest and thickest epithelium and might indicate an improvement of the condition. There were no significant changes in minimum stromal and minimum corneal thicknesses.
Epithelial thickness maps provide useful information for monitoring the progression of corneal ectasia after corneal collagen CXL, showing in this case, at least no further progression of the ectasia.
From London Vision Clinic (Reinstein, Gobbe, Archer, Couch); Department of Ophthalmology, St Thomas’ Hospital - Kings College (Reinstein), London, United Kingdom; Department of Ophthalmology, Weill Medical College of Cornell University, New York, New York (Reinstein); and Centre Hospitalier National d’Ophtalmologie, Paris, France (Reinstein).
Dr Reinstein has a proprietary interest in the Artemis technology (ArcScan Inc, Morrison, Colorado) and is the author of patents related to very high-frequency digital ultrasound administered by the Cornell Center for Technology Enterprise and Commercialization (CCTEC), Ithaca, New York. The remaining authors have no proprietary or financial interest in the materials presented herein.
Preparation in part fulfillment of the requirements for the doctoral thesis, University of Cambridge, for Dr Reinstein.
Correspondence: Dan Z. Reinstein, MD, MA(Cantab), FRCSC, FRCOphth, London Vision Clinic, 138 Harley St, London W1G 7LA, United Kingdom. Tel: 44 207 224 1005; Fax: 44 207 224 1055; E-mail: email@example.com