الفهرس | Only 14 pages are availabe for public view |
Abstract A great advancement had been accomplished in the field of LASIK since it was first practiced. The ultimate goal has always been to preserve as much as possible of the RSB to prevent post LASIK ectasia. Wherefore, the technology of Femtosecond laser has been used to achieve more safe and accurate results. The assessment of flap precision requires the appropriate tools. This was the reason behind using the high-speed non-contact Cirrus HD-OCT 5000 AS-OCT system, as it facilitates the high resolution cross-sectional imaging of the cornea and anterior segment and hence, the measurement of the corneal flap thickness. In this study, the statistical analysis of the data collected by AS-OCT showed that in each point of measurement, the FS laser scored less SD from the target flap than MMK. This marked difference makes FS laser the treatment of choice in cases of patients suffering from high refractive errors who need more stromal ablation, and patients with slightly thin corneas with moderate refractive errors. This would lead to preserve more RSB to prevent post LASIK ectasia. Additionally, both FS laser and MMK create meniscus flaps, but the asymmetry between the periphery and the center is much greater with MMK. Moreover, the meniscus flap created by FS laser is much thinner, which also helps in keeping of adequate RSB thickness. Finally, both groups of FS laser and MMK have similar visual outcomes. This indicates that the MMK makes a strong rival to FS laser only in this aspect. |