Corneal tomographic features of postrefractive surgery ectasia

Pooja Khamar, Ritika Dalal, Rachana Chandapura, Mathew Francis, Rohit Shetty, Everette J. R. Nelson, Rudy M. M. A. Nuijts, Abhijit Sinha Roy*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


The purpose of this study was to evaluate the tomographic features of postrefractive surgery eyes. This was a retrospective evaluation of clinical data. Three patients with post-LASIK (laser-assisted in situ keratomileusis) and two patients with post-SMILE (small incision lenticule extraction) ectasia were imaged with Scheimpflug imaging (SI, Pentacam) and optical coherence tomography (OCT, RTVue). Curvature and wavefront aberrations of the air-epithelium interface (A-E) and epithelium-Bowman's layer interface (E-B) were derived. OCT of normal and keratoconic eyes from an earlier study were compared with the data of the ectasia eyes. Curvature and aberrometry of the A-E interfaces were statistically similar between SI and OCT. However, OCT revealed a steeper and more aberrated E-B interface than A-E though correlation between them was inferior to the correlation for keratoconic eyes. Furthermore, the magnitude of differences between the A-E and E-B interfaces was greater in the ectasia eyes than the keratoconic eyes. OCT could possibly assist better in selecting appropriate treatment plan for postrefractive surgery ectasia eyes than conventional tomographers.

Original languageEnglish
Article number201800253
Number of pages8
JournalJournal of Biophotonics
Issue number2
Publication statusPublished - Feb 2019


  • ectasia
  • cornea
  • tomography
  • OCT
  • Bowman's layer
  • RISK

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