The results of femtolaser scleropuncture in experiments on isolated animal tissue (preliminary report)

The purpose of the study is to evaluate the results of femtolaser sclerotomy in the experiment on isolated eye of animal, as well as the prospects of applying the method of laser transscleral puncture of the sinus canal of sclera. Material and Methods. We performed a series of experiments on fresh scleral tissue of isolated pig eyes using industrial femtosecond laser PH-1SP with a wavelength of 1028 nm, pulse energy of 0.5-1.5 MJ, frequency of 1-20 kHz. Series of 10-15 pulses with duration less than 100 FS were performed. In order to assess the depth of femtosecond laser exposure to scleral tissue, as well as the quality of the obtained punctured holes, histological preparations were made, studied using routine light microscopy with multiplicity of magnifying up to ×400. Serial sagittal and frontal sections 15 µm thick and hematoxilin eosin staining were used. Results. Puncture channels of diferent confgurations with a minimum marginal coagulation of no more than 5 microns were obtained due to the efect of ablation of the scleral tissue. The maximum depth of the formed channels is 500 microns at a power of 1.5 MJ and a frequency of 10 kHz. Since the thickness of the scleral tissue of the human eye in the limbal zone is 600-800 µm, there is prospect of using a femtosecond laser for the laser transscleral puncture of the schlemm channel. Conclusion. The infuence of femtosecond laser on tissue of sclera is characterized by the almost complete absence of heat, the coagulation efect and the pronounced depth of the ablation, thus it is possible to discuss the use of femtosecond laser for the laser transscleral puncture of the sclera sinus channel.