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[OCT Observations] Screening for Refractive Surgery

Raise awareness on the importance of Epithelial Thickness Mapping (ETM) in refractive surgery screening.

Case History

Woman , 27 years old, medical history of Grass allergies.
Candidate to Refractive surgery with papillae on tarsal conjunctiva.



Clinical Findings

Corneal Topography (1A 1B) shows irregular corneal steepening in inferior location corresponding at the same location with eptihelium hyperplasia observed on ETM (3A 3B).

  • Pachymetry doesn't show any irregularities (2A 2B).
  • Epithelium Hyperplasia is correlated with a DGM stage (4B) and in this case we observe that Right eye (4A) has more pronounced Hyperplasia corresponding to DGM grade.
  • Epithelium Hyperplasia induces corneal curvature changes due to DGM and dry eye syndrome.
  • Epithelium hyperplasia may reflect a reaction to the micro lesions caused by hyperosmolar stress or micro abrasive effect induced by blinking on the ocular surface under condition of moderate dry eye .

Corneal Hyperplasia is a compensatory response to changes in the curvature such as in the case of keratoconus or radial keratotomy.

Variability of the distribution of ETM and total pachymetry are factors used to differentiate between hyperplasia induced by dry eye syndrome and ectatic corneas.


Wide ETM (10mm) offers better correlation with corneal topography.
Dry eye syndrom can cause epithelium changes  that’s why corneal topography analysis is inseparable of ETM in refractive surgery, keratoconus screening  and to ensure having the best keratometry for premium surgery.



Adil El Matouhi_2




Mr. Adil El Maftouhi
is Orthoptist and Ocular imaging specialist in Centre Ophtalmologique de Rive Geneva, Switzerland and in CHNO XV-XX Paris, France. He is the author of international books on OCT and OCT-A. He has also published several peer-reviewed articles like "OCT and dry eye syndrome" and « OCT : the intelligence of the epithelium ».

Adil El Maftouhi works on the development and operation of the various imaging systems available in Ophthalmology to exploit the potential of each system for the benefit of the clinic.

At the same time, he contributes to the development of new imaging applications and software, particularly on OCT technology. Mr. El Maftouhi also participates in clinical and pharmacological research projects in the field of medical retina, glaucoma and low vision.

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