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%.

To explore the offset distribution of pupillary centres, the offset between the pupil centre and the coaxially sighted corneal light reflex (P-Dist) and their correlation in femtosecond laser combined with excimer laser in situ keratomileusis.Methods: Randomly selected 194 patients (398 eyes) who underwent femtosecond-assisted laser in situ keratomileusis with preoperative use of WaveLight Allegro Topolyzer Corneal Topography (WaveLight Laser Technologies AG, Erlangen, Germany) to measure the pupil size and centre position. 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.Results: The P-Dist was 0.214 ± 0.092 mm in the right eyes and 0.228 ± 0.105 mm in the left eyes (P = .041). Under scotopic conditions, the pupil centre of left eye X-axis was À0.046 ± 0.091 mm, the right eye was À0.152 ± 0.084 mm, with significant differences (P = .015), and the Y-axis direction showed no significant changes (P = .062). The white to white was positively correlated with changes of pupil diameter (scotopic pupil diameter-photopic pupil diameter) (r = 0.270, P < .001). The equivalent spherical mirror and measured centroid shift were negatively correlated (r = À0.214, P = .002). Conclusion:The angle kappa of the right eye is smaller than that of the left eye and from scotopic to photopic condition, the pupil centroid shift of both eyes to the nasal inferior side. If the cornea is too large, the low illumination environment should be maintained during the operation to improve the efficiency of pupil matching.Abbreviations: ACD = anterior chamber depth, P-Dist = the pupil centre and the coaxially sighted corneal light reflex, SE = equivalent spherical mirror, WTW = white to white.

Background To explore the dynamic distribution of pupil size and center,the eccentricity distribution of angle kappa, and its correlation with other biomechanics about suitable for excimer laser refractive surgery. Methods Randomly selected 225 patients (407 eyes) who underwent femtosecond laser combined with excimer laser in situkeratomileusis,preoperative use of Wavelight Allegro Topolyzer Corneal Topography ( Wavelight Laser Technologies AG, Erlangen, Germany ) 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 of P-Dist (the eccentricity between the pupil center and the coaxially sighted corneal light reflex point) is 0.225 ± 0.102 mm, and 80% of the eyes are ≤ 0.30 mm.The coaxially sighted corneal light reflex point is mainly deviated to the superior temporal side of the corneal center (34%).Under the dark light condition, the x-axis of the left eye was: -0.046 ± 0.091 mm, the x-axis of the right eye was: -0.152 ± 0.084 mm, with statistical difference ( P = 0.015) (the right eye shifted to the temporal side), the y-axis direction had no statistical change ( P = 0.062). The WTW was positively correlated with changes of pupil diameter (dark pupil diameter-bright pupil diameter) ( r = 0.270, P <0.001).The SE and measured centroid shift was negative correlated ( r = - 0.214, P = 0.002). Conclusion The pupil of the left eye becomes smaller, the anterior chamber becomes shallower, and the angle kappa increases relative to the right eye.In patients with large WTW, a darker light environment is maintained during the operation to improve the efficiency of pupil matching.The dynamic change of angle kappa in high myopia population is small.

Purpose: To investigate dynamic pupil changes after orbital blowout fracture repair. To compare postoperative changes in under photopic and mesopic pupil size and center position after orbital blowout fracture repair surgery. Methods: The study evaluated 19 eyes. Pupils were imaged for pupil size and center position before and 3 months after orbital blowout fracture repair surgery. Pupil size changes were measured, and the correlation between preoperative and postoperative pupil centroid shift was evaluated. Results: After repair, operative eyes exhibited a growth of 9.3% AE 8.6% in pupil size, and contralateral eyes showed a growth of 8.6% AE 8.2% (P ¼ 0.011, P ¼ 0.007). Similar findings were noted in mesopic conditions. Under mesopic conditions, the pupil of operative eyes in medial orbital wall fracture deviated 0.030 AE 0.019 mm towards the nasal side along the X-axis (P ¼ 0.031). The postoperative orbital floor fracture group demonstrated statistical significance at a spatial frequency of 5 (P ¼ 0.041). Conclusions: Orbital blowout fracture repair surgery affects pupil size and center position.

This study reveals that the environment temperature will affect the operating voltage and the image quality of ChLCD. The data demonstrate that with the decrease of temperature the operating voltage will be increased and we found that we can maintain the operating voltage by increase the addressing time.