Surface roughness investigations of excimer-laser-ablated cornea

The earlier investigations showed that the corneal haze can be due to the scattering effect of the excimer laser induced surface structure. In this paper a comparative study is presented regarding the development of these. Several human corneas were irradiated by an ArF excimer laser. The applied fluence was 193 mJ/cm2. The developed surface structures after each excimer pulse were investigated by an atomic force microscope under physiological salt solution in natural environment. It was found that the structures of cells and fibers forming the cornea were observable on the ablated surface in the form of surface roughness. Scanning electron microscopic observations were also performed to compare the two surface investigation methods. It was found that this showed the same structures, but differently from the atomic force microscopic observation some distortions appeared produced by preparation processes of the samples, which were necessaries for the electron microscopic investigations.