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2007, Number 1

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Rev Med Hosp Gen Mex 2007; 70 (1)

Changes in corneal forward shift after LASEK

Alvarado-Castillo B, Vázquez-Maya L

Language: Spanish
References: 19
Page: 12-17
PDF size: 165.55 Kb.


ABSTRACT

Purpose: To evaluate the forward shift of the posterior corneal surface after Laser-assisted Subepithelial Keratectomy (LASEK). Material and methods: Forty-four eyes (twenty two patients) that underwent LASEK were reviewed prospectively. The uncorrected visual acuity, spherical equivalent, intraocular pressure (IOP) and pachymetry were obtained prior to surgery and 3 weeks, 3 and 4 months after. The change in the elevation of the posterior corneal surface was assessed using the difference map of an Orbscan II ( B & L), considering the central measures at 3 weeks, 3 and 4 months. Stepwise regression was used to assess the changes with the pachymetry, microns of ablation, residual corneal thickness and IOP. Results: The posterior corneal surface displayed a mean forward shift of 24.86 µm at 3 weeks after LASEK, 17.97 µm at 3 months and 15.68 µm at 4 months, with a significant reduction depending on the time course (p ‹ 0.01). A statistically significant correlation was found between the residual corneal bed thickness and the forward shift of the cornea (p ‹ 0.05). Conclusions: LASEK induced a forward shift of the posterior corneal surface early postoperatively that gradually reduces.


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