Thereinto, the optical quality is believed to be the most important indicator. In order to effectively evaluate the effect after the refractive surgery, different kinds of examination methods and evaluating indicators were used in previous work. As a comparison, femtosecond laser is utilized in the FS-LASIK surgery to generate the corneal flap, and excimer laser is applied to ablate the corneal stroma subsequently.
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When performing the SMILE surgery, a corneal stromal lenticule is firstly made with the femtosecond laser and then extracted from a small side incision. In the field of corneal refractive surgery, both small-incision lenticule extraction (SMILE) and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) have been extensively applied. Meanwhile, the refractive surgery develops quite quickly in recent years and increasing numbers of patients with high myopia choose the surgery to correct the refractive errors. This research was approved by the ethics committee of Xiangya Hospital and the IRB approval number is 201612074.īeing a common eye ametropia disease, high myopia has now widely existed in the general population and its incidence rate still keeps increasing so far. The combination of OQAS and iTrace analyzer is a valuable complementary measurement in evaluating the optical quality after the refractive surgery. SMILE was superior to FS-LASIK at the correction effect and optical quality for high myopia. The optical quality descended after SMILE and FS-LASIK. The total high-order wavefront aberration and coma aberration at 1 month were higher after FS-LASIK than SMILE.
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The spherical and coma aberration increased significantly in both groups. The total high-order wavefront aberration increased significantly after FS-LASIK. (3) The total wavefront aberration, total low-order wavefront aberration, defocus and astigmatism aberration as well as trefoil aberration reduced significantly in both groups. OSI was significantly lower after SMILE than FS-LASIK. SR and MTF cutoff were significantly higher after SMILE than FS-LASIK. (2) SR and MTF cutoff reduced and OSI increased significantly after SMILE and FS-LASIK. ResultsĪfter the operation: (1) SE and astigmatism declined and UDVA increased significantly in both groups, and UDVA was better after SMILE than FS-LASIK. Between the two groups the spherical equivalent (SE), astigmatism, uncorrected distant visual acuity (UDVA), strehl ratio (SR), modulation transfer function cutoff frequency (MTF cutoff), objective scatter index (OSI) and wavefront aberrations were analyzed and compared before surgery and at 1, 6 and 12 months after surgery. The OQAS and iTrace analyzer were used for optical quality inspection. Methodsĥ1 high myopia eyes after SMILE and 49 high myopia eyes after FS-LASIK were enrolled and divided into two groups retrospectively. To compare the correction effect and optical quality after small-incision lenticule extraction (SMILE) and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia.