Changes in retinal nerve fiber layer thickness following mechanical microkeratome-assisted versus femtosecond laser-assisted LASIK
Received 19 July 2013
Accepted for publication 22 August 2013
Published 25 September 2013 Volume 2013:7 Pages 1919—1922
Checked for plagiarism Yes
Review by Single anonymous peer review
Peer reviewer comments 4
Mohamed Hosny,1 Rania M Zaki,1 Rania A Ahmed,1 Noha Khalil,1 Hoda M Mostafa1
1Department of Ophthalmology, Cairo University, Cairo, Egypt
Purpose: To study the influence of the transient elevation of intraocular pressure during suction in laser-assisted in situ keratomileusis (LASIK) on the retinal nerve fiber layer (RNFL) thickness both in microkeratome assisted and femotsecond (FS) LASIK.
Patients and methods: An interventional case series that included 40 eyes suffering from myopia who were candidates for LASIK. All underwent Wave Front Guided LASIK by the same surgeon using the VisX CustomVue platform. A corneal flap was created in 20 eyes using a mechanical microkeratome Moria M2 (MMK), while the IFS IntraLase™ was used in the remaining 20 eyes. Mean suction time was recorded from “Suction ON” to “Suction OFF” time. Optic cube and RNFL thickness analysis using Spectral Domain Optical Coherence Tomography (SD-OCT) Cirrus-HD was completed before, and 1 month after LASIK.
Results: The study included 40 eyes of 20 patients. All were females with mean age 33.5 ± 6.4 years. Mean preoperative spherical equivalent was −3.62 ± 2.31D. Average preoperative RNFL thickness was 94.6 ± 12.1µm in MMK group while the postoperative average thickness was 95.1 ± 11.9 um with no statistically significant difference (P-value: 0.37). Average preoperative RNFL thickness was 108.28 ± 8.4 µm in FS group compared to 108.38 ± 11.2 µm in the postoperative average with no statistically significant difference (P-value: 0.94). Mean “Suction ON” to “Suction OFF” time was 22 seconds in the MMK group compared to 41 seconds in the FS group.
Conclusion: The rise of intraocular pressure during application of suction ring in LASIK surgery does not affect the RNFL thickness as measured by SD-OCT, whether the flap is created by MMK or FS.
Keywords: intraocular pressure, laser-assisted in situ keratomileusis, retinal thickness
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Download Article [PDF] View Full Text [HTML][Machine readable]