A corneal surface study in patients after laser keratomilesis

The cornea of the human eye is not only refracts the light, but also acts as a convex mirror, which reflects the surroundings. In ophthalmology, an image reflected by its anterior surface is known as the 1st Purkinje image. Characteristics of this image are determined by the properties of the light source and the state of corneal surface. At the present time, there are many methods in ophthalmology to study various properties of the cornea, but most of them either require expensive equipment or are qualitative and not informative. Meanwhile, a “shining” characteristic of the cornea in general is assessed subjectively and is not properly addressed in the ophthalmic literature. Our work was conducted to study the possibility of applying the method of measuring the reflective ability of the cornea to measure the state of its anterior surface. Our study involved men and women aged 18–45 years after laser-assisted in situ keratomilesis (LASIK). With our new method of measuring the corneal reflectance, we investigated patients before surgery, day 1 post-op and after 1 week. Each study case included a measurement of the reflectivity of the cornea after blinking, and after 15 sec. We found that on the day 1 after surgery corneal reflectivity increases, at the same time, 15 sec after blinking it is reduced to normal. This suggests a reduction of the tear film stability and that the patients had some symptoms of corneal syndrome, and as a consequence, increased tear production. One week after surgery, we observed a different picture: the reflective power of the cornea decreased. We consider this to be a sign of corneal nerves damage and decreased tear production.

LASIK, cornea, reflective, contrast, LASIK, patch of light, tear film, corneal flap