Purchase this article with an account.
A. pennos, H. Ginis, I. Pentari, G. Kymionis, G. Kounis, I. G. Pallikaris; Differencies Between Light Scattering Properties in Corneall Flaps Created With Femtosecond Laser and a Mechanical Microkeratome. Invest. Ophthalmol. Vis. Sci. 2010;51(13):2869.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The purpose of this study was to evaluate wether possible differences in surface quality between flaps created with a femtosecond laser and a mechanical microkeratome result to significant differences in light scattering properties.
Twelve freshly enucleated porcine eyes were obtained from a local abattoir. Six flaps were created by the Intralase (AMO, Illinois, USA) femtosecond laser and another six were created by a mechanical microkeratome (Carriazo-Pendular, SCHWIND, Kleinostheim Germany). Flap thickness was estimated by comparing corneal pachymetry (Sonogage, Ohio USA) immediately prior to and after the flap creation. All flaps were removed from the eyes and immersed in a dextran solution (20% in saline), to ensure a given (physiological) hydration state. In order to measure the amount of light scatter, a setup involving a CCD camera, a custom flap cell and a computer monitor was employed. During the measurement, images of disks displayed on the computer screen were recorded through the flaps and appropriate processing allowed the calculation of forward light scatter that is induced both by the surface roughness on the flaps and bulk scattering in the corneal tissue.
The median scatter coefficients were 0.3679 for the flaps cut with the femtosecond laser, and 0.3880 for the flaps cut with the mechanical microkeratome. The distributions of the 2 groups did not differ significantly (Mann-Whittney, U = 22 n1=n2=6 P= 0.2877 > 0.05).
Although the mechanisms of flap creation are fundamentally different, there seems to be no significant difference in flap transparency. Moreover, by examining the relationship of the total light scattering properties of the flaps with their thickness it may be suggested that light scattering is mostly a result of bulk rather than surface scattering.
This PDF is available to Subscribers Only