AIM： To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol. METHODS： This is a retrospective interventional study. Fifty-four eyes of 27 patients （m...AIM： To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol. METHODS： This is a retrospective interventional study. Fifty-four eyes of 27 patients （mean age, 50.2±7.5y） who underwent presbyopia correction with an aspheric micro-monovision protocol were enrolled. The values of modulation transfer function （MTF） cutoff frequency, Strehl ratio, objective scattering index （OSI） and accommodation range were quantitatively assessed using the HD analyzer. Preoperative and postoperative contrast sensitivity （CS） at far （2.5 m） and near （40 cm） distance and higher-order aberrations （HOAs） were analyzed. Subjective visual satisfaction was evaluated by self-reported questionnaire regarding optical visual symptoms. RESULTS： One year after presbyopia correction, no significant differences were found in the MTF cutoff frequency, Strehl ratio and OSI, however, the lID analyzer accommodation range significantly differed postoperatively （P=0.004）. Postoperative CS at 12 and 18 cpd at near showed statistically significant improvement （P=0.020 and 0.008, respectively）. Visual performance by self-reported questionnaire revealed satisfactory results in terms of subjective visual quality improvement. CONCLUSION： Objective optical quality parameters show good visual outcomes. Subjective visual quality assessed by self-reported questionnaire in the presbyopia correction group show satisfactory results.展开更多
In this paper we present the recent research results in the field of vision correction and supernormal vision according to the actual measurements of the wave-front aberrations and the corneal surface topography,the c...In this paper we present the recent research results in the field of vision correction and supernormal vision according to the actual measurements of the wave-front aberrations and the corneal surface topography,the clinical detection of the visual function and the laser corneal refractive surgery,and the optimization of the optical system. These include the features of the aberrations of human eye with different pupil sizes,different fields of view and temporal accommodation,the influence of the polychromatic illumination of the visible wavelength on the supernormal vision,and the effect of the existing laser corneal refractive surgery on the wave-front ab-errations of the eye. It is shown that the wave-front aberration of human eye is of temporal variation and of synthesis with multi impact factors. To achieve super-normal vision,an optimum engineering data for the customized laser corneal sur-gery should be firstly acquired,which may involve the dynamic free-form optical surface. Although the myopia can be corrected by the laser in situ keratomileusis(LASIK) in a certain degree,it brings about negative effects under scotopic condi-tions.展开更多
AIM： To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial leng...AIM： To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial length.METHODS： An effective eye model was introduced by the ocular components of human eye including refractive indexes, surface radius（r1, r2, R1, R2） and thickness（t, T） of the cornea and lens, the anterior chamber depth（S1） and the vitreous length（S2）. Gaussian optics was used to calculate the change rate of refractive error per unit amount of ocular components of a human eye（the rate function M）. A new criterion of myopia was presented via an effective axial length.RESULTS： For typical corneal and lens power of 42 and 21.9 diopters, the rate function Mj（j=1 to 6） were calculated for a 1% change of r1, r2, R1, R2, t, T（in diopters） M1=＋0.485, M2=-0.063, M3=＋0.053, M4=＋0.091, M5=＋0.012, and M6=-0.021 diopters. For 1.0 mm increase of S1 and S2, the rate functions were M7=＋1.35, and M8=-2.67 diopter/mm, respectively. These rate functions were used to analyze the clinical outcomes in various applications including laser in situ keratomileusis surgery, corneal cross linking procedure, femtosecond laser surgery and scleral ablation for accommodation.CONCLUSION： Using Gaussian optics, analytic formulas are presented for the change of refractive power due to various ocular parameter changes. These formulas provide useful clinical guidance in refractive surgery and other related procedures.展开更多
文摘AIM： To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol. METHODS： This is a retrospective interventional study. Fifty-four eyes of 27 patients （mean age, 50.2±7.5y） who underwent presbyopia correction with an aspheric micro-monovision protocol were enrolled. The values of modulation transfer function （MTF） cutoff frequency, Strehl ratio, objective scattering index （OSI） and accommodation range were quantitatively assessed using the HD analyzer. Preoperative and postoperative contrast sensitivity （CS） at far （2.5 m） and near （40 cm） distance and higher-order aberrations （HOAs） were analyzed. Subjective visual satisfaction was evaluated by self-reported questionnaire regarding optical visual symptoms. RESULTS： One year after presbyopia correction, no significant differences were found in the MTF cutoff frequency, Strehl ratio and OSI, however, the lID analyzer accommodation range significantly differed postoperatively （P=0.004）. Postoperative CS at 12 and 18 cpd at near showed statistically significant improvement （P=0.020 and 0.008, respectively）. Visual performance by self-reported questionnaire revealed satisfactory results in terms of subjective visual quality improvement. CONCLUSION： Objective optical quality parameters show good visual outcomes. Subjective visual quality assessed by self-reported questionnaire in the presbyopia correction group show satisfactory results.
基金Supported by the National Natural Science Foundation of China (Grant No. 60438030)the Key Research Foundation of Scientific and Technical Committee of Tianjin City of China (Grant No. 033183711)
文摘In this paper we present the recent research results in the field of vision correction and supernormal vision according to the actual measurements of the wave-front aberrations and the corneal surface topography,the clinical detection of the visual function and the laser corneal refractive surgery,and the optimization of the optical system. These include the features of the aberrations of human eye with different pupil sizes,different fields of view and temporal accommodation,the influence of the polychromatic illumination of the visible wavelength on the supernormal vision,and the effect of the existing laser corneal refractive surgery on the wave-front ab-errations of the eye. It is shown that the wave-front aberration of human eye is of temporal variation and of synthesis with multi impact factors. To achieve super-normal vision,an optimum engineering data for the customized laser corneal sur-gery should be firstly acquired,which may involve the dynamic free-form optical surface. Although the myopia can be corrected by the laser in situ keratomileusis(LASIK) in a certain degree,it brings about negative effects under scotopic condi-tions.
基金Supported by an Internal Research of New Vision Inc.,Taipei,Taiwan
文摘AIM： To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial length.METHODS： An effective eye model was introduced by the ocular components of human eye including refractive indexes, surface radius（r1, r2, R1, R2） and thickness（t, T） of the cornea and lens, the anterior chamber depth（S1） and the vitreous length（S2）. Gaussian optics was used to calculate the change rate of refractive error per unit amount of ocular components of a human eye（the rate function M）. A new criterion of myopia was presented via an effective axial length.RESULTS： For typical corneal and lens power of 42 and 21.9 diopters, the rate function Mj（j=1 to 6） were calculated for a 1% change of r1, r2, R1, R2, t, T（in diopters） M1=＋0.485, M2=-0.063, M3=＋0.053, M4=＋0.091, M5=＋0.012, and M6=-0.021 diopters. For 1.0 mm increase of S1 and S2, the rate functions were M7=＋1.35, and M8=-2.67 diopter/mm, respectively. These rate functions were used to analyze the clinical outcomes in various applications including laser in situ keratomileusis surgery, corneal cross linking procedure, femtosecond laser surgery and scleral ablation for accommodation.CONCLUSION： Using Gaussian optics, analytic formulas are presented for the change of refractive power due to various ocular parameter changes. These formulas provide useful clinical guidance in refractive surgery and other related procedures.
