%0 Journal Article
%T Effect of 60£¿kHz and 150£¿kHz Femtosecond Lasers on Corneal Stromal Bed Surfaces: A Comparative Study
%A Cristina Monterosso
%A Alessandro Galan
%A Elisabetta B£¿hm
%A Alfonso Zampini
%A Mohit Parekh
%A Luigi Caretti
%J ISRN Ophthalmology
%D 2013
%R 10.1155/2013/971451
%X Purpose. To compare the effect of 60£¿kHz and 150£¿kHz femtosecond (FS) laser on the corneal stromal bed surfaces (SBS). Methods. Sixteen human donor corneal tissues unsuitable for transplantation were used. Anterior and posterior lamella was obtained using 60£¿kHz and 150£¿kHz FS laser. A standard depth of 400£¿¦Ìm was set for anterior lamellar keratoplasty (ALK) and endothelial lamellar keratoplasty (ELK). The quality and smoothness of the SBS post-FS laser dissection were graded for statistics. Results. No intraoperative complications were found. The side cuts were straight, and the SBS appeared smoother in cuts obtained using 150£¿kHz. The average values of the SBS quality of the anterior lamellar cut were found to be 2.25 (¡À0.28) for 60£¿kHz and 3.125 (¡À0.25) for 150£¿kHz ( ). Whereas, 2 (¡À0.4) for 60£¿kHz and 2.75 (¡À0.28) for 150£¿kHz ( ) was the quality observed in endothelial cuts. No significant difference was found between anterior and posterior cuts performed using the same FS laser (60£¿kHz or 150£¿kHz) ( ). Conclusions. The 60£¿kHz and 150£¿kHz FS lasers are equally effective in performing lamellar dissection for ALK and ELK. 150£¿kHz FS laser allows a tighter spot and layer separation which creates a slightly smoother SBS. 1. Introduction Corneal lamellar keratoplasty (LK) is a surgical technique that allows preserving healthy portions of the cornea while selectively replacing the dysfunctional layers. The outcome of LK has also shown improvements of the procedure by decreasing surgical risk, enhancing healing process and quick rehabilitation as compared to penetrating keratoplasty (PK) [1]. Since the last decade, the femtosecond (FS) laser technology has been developed to perform laser assisted in situ keratomileusis (LASIK) refractive surgery. It reduced the complication rate due to LASIK flap creation, improved the predictability of flap dimensions, and improved the quality of the optical surface, compared to microkeratome surgery [2¨C8]. The reliability and safety have been evaluated using IntraLase FS (iFS, Abbott, Irvine, CA, USA) laser which have already been verified extensively for LASIK and more recently for endothelial lamellar keratoplasty (ELK) [9, 10]. The FS uses pulses to create corneal resection. The quality of the surfaces obtained is determined by programmable parameters like the laser spot and layer separation and the energy delivered per pulse. It was therefore evaluated that, with closer spots, the energy required for the cuts is less and with less energy surface gets smoother [2]. The early stage of this technology allowed the firing
%U http://www.hindawi.com/journals/isrn.ophthalmology/2013/971451/