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AIM: To explore the dynamic distribution of pupil size and center, the eccentricity distribution of corneal light reflection, and its correlation analysis about suitable for femtosecond laser combined with excimer laser in situ keratomileusis.METHODS: Randomly selected 225 patients(407 eyes)who underwent femtosecond laser combined with excimer laser in situ keratomileusis at Yanbian University Hospital in 2019 from January to May, preoperative use of Wavelight Allegro Topolyzer Corneal Topography to measure the pupil size and center position, the German Wavelight EX500 excimer Laser(500Hz)records the deviation between the pupil center and the coaxially sighted corneal light reflex when the patient is supine. RESULTS:The average displacement distribution between the center of the cornea and the center of the pupil is 0.322±0.194mm, and 64% of the eyes are ≤0.40mm. The average displacement distribution of P-Dist(the eccentricity between the pupil center and the coaxially sighted corneal light reflex point)is 0.225±0.102mm, and 80% of the eyes are ≤0.30mm. The coaxially sighted corneal light reflex point is mainly deviated to the superior temporal side of the corneal center(34%). The X-axis of the left eye in low light conditions: -0.061±0.084mm, and the X-axis of the right eye: -0.016±0.059mm(P=0.002)(the left eye shifted to the temporal side in the dark light). The corneal transverse diameter(WTW)was positively correlated with changes in pupil diameter(dark pupil diameter-bright pupil diameter)(r=0.270, PCONCLUSION: The left eye should be adjusted to a position of the machining center within 0.061mm. If the cornea is too large, try to maintain a dark light environment during the operation to improve the efficiency of pupil matching. This study further confirms the necessity of rationally positioning the cutting center under different angle kappa states.

AIM: To investigate the effect of inclination and eccentricity of intraocular lens(IOL),on optical imaging quality via wavefront aberration optical path system.METHODS: The spherical IOL Sensar AR40e, the aspherical monofocal IOL Tecnis ZA9003, and the aspheric multifocal IOL Tecnis ZM900 were measured at the center of the center using a laboratory-built Hartmann-Shack IOL wavefront aberration path system at 5.0mm simulated pupil diameter. 0, 0.2, 0.4, 0.6, 0.8mm, the effect on the optical imaging quality when tilting 5°, 10°, 15°, 20°, 25° to the nasal side and the temporal side, and quantitative imaging quality by high-order aberration and modulation transfer function.RESULTS: The Temnis ZA9003 MTF value was higher than AR40e and Tecnis ZM900 when inclinationed within 5°, while the three IOL MTF values were significantly different when inclinationed 5°, 10°, 15°, and 20°. Tecnis ZA9003 The IOL inclination angle was significantly positively correlated with the coma(r=0.842, Pr=0.229, P=0.241). The three IOL MTF values were obtained when the eccentricity was 0.6 and 0.8 mm. Significant differences(both PCONCLUSION: When the inclination of aspheric IOL(-0.27μm spherical aberration)is less than 5°and the eccentricity is less than 0.4mm, aspherical IOL has a better imaging quality than that of spherical IOL. Tecnis ZM900 IOL has a lower optical imaging quality than that of spherical and aspheric IOL when the eccentricity of IOL is more than 0.4mm.

AIM:To determine the pathological changes in ocular surfaces dry eye excessive evaporation non-obese diabetic(NOD)mice model and to preliminarily explore the feasibility of diabetic dry eye model.METHODS: In this study, 40 females NOD mice were selected. The experimental group consisted of NOD mice that were diagnosed with diabetes while the normal control group consisted of those NOD mice without spontaneous diabetes. Hypodermic injection of Scopolamine hydrobromide(0.5mg/0.2mL)was administered under 40% humidity to the experimental group and placed in a controlled drying box for 12h a day. This was to achieve a dry eye model. Testing indicators on the 1, 7, 10 and 14d after modeling, phenol red thread test was used to measure tear secretion and the eye sections were stained with periodic acid-Schiff(PAS)to examine the morphology and number of conjunctival goblet cells. On the 10d after modeling, the changes in the corneal epithelium were visualized after staining with hematoxylin. RESULTS:For the NOD mice of the experimental group, the tear secretion was gradually decreased with timing, while there were no obvious changes in the normal control group. The volume of the conjunctival goblet cells of the experimental group became larger, and on the 1d after the molding, the experimental group had decreased density of the goblet cells when compared with the normal control group(P=0.008). From the 7d after the molding, as the time was prolonged, the density of the goblet cells was gradually decreased and the differences between the two group at same time point were significant(all PCONCLUSION: Dry eye model of NOD mice was preliminary established, and the changes of ocular surface were similar to those of dry eye in the clinic.

Purpose. To analyze the distribution of the offset between the pupil center and the coaxially sighted corneal light reflex (P-Dist), the effects of 50% and 100% angle kappa adjustments on refractive and visual quality in patients with moderate myopia were investigated. Methods. A randomly selected 254 patients (254 eyes) with moderate myopia who underwent femtosecond laser-combined LASIK were examined. During the operation, the P-Dist of the patients was recorded by the x- and y-axis eyeball-tracking adjustment program of the WaveLight Eagle Vision EX500 excimer laser system. Preoperatively and 3 months postoperatively, the WaveLight® ALLEGRO Topolyzer was used to measure the pupil size and center position, and the wavefront sensor was used to measure the wavefront aberrations. The visual function tester (OPTEC 6500) measured contrast sensitivity. Results. The average P-Dist was 0.220 ± 0.102 mm. When the P-Dist >0.220 mm, the postoperative residual cylinder was 0.29 ± 0.34 D in the group with the 50% adjustment and 0.40 ± 0.32 D in the 100% group, which was significantly higher than the 50% group P=0.036. The coma was 0.21 ± 0.17 μm in the 50% adjusted group and 0.34 ± 0.25 μm in the 100% group, which was significantly higher than that in the 50% group P=0.021. At the 1.5 c/d spatial frequency, contrast sensitivity in the adjusted 100% group was significantly lower than that in the 50% group under visual glare conditions P=0.039. Conclusion. The postoperative visual acuity and spherical equivalent were not affected in the two groups. However, when P-Dist >0.220 mm, the residual astigmatism and coma were lower in the 50% group. Individualized operations for those with moderate myopia and large-angle kappa in which 100% adjustment is chosen may not result in a better visual quality effect than 50%.