[Scanning microscopy comparison of keratotomies using a diamond or steel knife]

We have compared on 4 cadaver eyes the aspect of keratotomies obtained with a diamond blade or a steel blade. We used the scanning electron microscope for the comparison. The incisions with diamond blade are much thinner than the incisions with steel blade. However the steel blade produced regular and smooth keratotomies. Whatever the blades, the microscopic appearance of the penetration was much better than the exit. The choice between cutting instruments for keratotomy depends upon these results and financial factors.