The advantages of using the 223 nm compared with 193 nm radiation wavelength for ophthalmic applications

摘要

The results experimental investigations of an interaction of the UV laser radiation with human eye cornea are described. In experiments the ArF (193-nm), KrCl (223-nm), KrF (248-nm) excimer lasers were used. The transmission spectra in UV region, the ablation rate and traumatic effects of different wavelengths to the human eye cornea were studied in detail. The biological safety of using the short-pulsed UV radiation from the point of view of chromosome rearrangement in the cells of eye has been shown. The UV ophthalmic laser systems based on the ArF (193-nm) and the KrCl (223-nm) excimer lasers were created and comparative analysis of using ones in ophthalmology was performed. The system with the radiation wavelength of 223-nm of the KrCl excimer laser for refractive surgery was shown to have several medical and technical advantages over the system with the traditionally used radiation wavelength of 193-nm of the ArF excimer laser. In addition the use of the wavelength of 223-nm extends functional features of the system, allowing to make not only correction of refractive errors and therapeutic procedures but also to treat such ocular diseases as the herpes simplex virus. For the first time the application of UV excimer lasers (193, 223 and 248-nm) for herpetic keratitis treatment was investigated. The advantages and disadvantages of using each radiation wavelengths for healing efficiency of simplex herpes virus were demonstrated. Optimal laser radiation parameters for the treatment of the herpetic keratitis were determined. The results of clinical trials are presented.