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Background High order aberrations and scattered light may be the main influencing factors of visual quality after phacoemulsification combined the aspherical IOL implantation.However,the study on objectively assessing the impact of them is little.Objective This study was to assess the impact of high order aberrations and scattered light on visual quality after phacoemulsification combined the aspherical IOL implantation.Methods A series cases-observational study was performed.Sixty-seven eyes of 53 patients who finished phacoemulsification and aspherical IOL implantation for at least 3 months in Tianjin Eye Hospital from February to August 2014 were enrolled.The root mean square (RMS) of total aberrations and high order aberrations was measured under the 4 mm pupil diameter with i-Trace aberrometer,including general high order aberrations,spherical aberrations,coma,and trefoil of entire eye,cornea and internal optics.The correlations between ocular aberrations and corneal or internal optic aberrations were analyzed.Objective scatter index (OSI) and objective visual quality parameters were measured,including MTF cut off frequency (MTF cut off),strehl ratio (SR) and OQAS values (100％ OV,20％ OV,9％ OV) with OQAS Ⅱ,and the correlations between the objective visual quality parameters and OSI,ocular aberrations,corneal aberrations or internal optic aberrations were analyzed.In addition,the correlations between OSI and ocular,corneal or internal optic aberrations were evaluated.Writen informed censent was obtained from each patient before entering the study.Results Ocular aberrations were significantly positively correlated with corneal or internal optic aberrations (r=0.255-0.586,all at P＜0.05;r=0.582-0.907,all at P＜0.01),and the associations between internal optic and ocular aberrations was stronger than those between corneal and ocular aberrations.The objective visual quality parameters were negatively correlated with ocular,corneal and internal optic aberrations (r=-0.247--0.675,all at P＜0.05;r =-0.245--0.497,all at P＜0.05;r =-0.246--0.513,all at P＜0.05) as well as with OSI (r =-0.620--0.781,all at P＜0.01).Most of the associations between internal optic aberrations and objective visual quality parameters were stronger than those of corneal aberrations.Furthermore,ocular,corneal and optical aberrations were all positively correlated with OSI (r =0.396-0.727,all at P＜0.01;r =0.320-0.522,all at P＜0.05;r =0.319-0.598,all at P＜0.01).Conclusions High order aberrations and scattered light seem to interact with objective visual quality in aspherical IOL implanted eyes,and the correlation between internal optic aberrations and ocular aberrations tends to be stronger than that of corneal aberrations.
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Objective To develop a measurement method for determination of optical parameters of a red blood cell ( RBC) suspension based on the measurement of spatial scattered light signals without using an integrating sphere.Methods Multiple independent photoelectric sensors and light intensity modulation were used to obtain the measured values of diffuse reflectance,diffuse transmittance and collimated transmittance.The measured data results were imported into a Monte Carlo simulation based RTE to inversely determine the absorption coefficient, scattering coefficient and anisotropy factor of the measured sample using a new perturbation method.Results The described measurement method was applied to determine the optical parameters of a polystyrene microsphere suspension with a mean diameter of 2.6μm,and the results were essen-tially consistent with the calculated optical parameters by Mie code.Then, the RBC suspension was used for testing optical parameters,and the results were basically consistent with the parameters in the literature.Conclusion The system based on the measurement of spatial scattered light signals without using an integrating sphere will provide a quick and accurate approach for quantitative analysis of free hemoglobins and RBC suspensions.
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To analyze the significance of intraocular scattered light and contrast sensitivity in cataract patient's visual quality.METHODS: Seventy-three cases of cataract patients ( 120 eyes ) in our department from January 2012 to January 2014 were selected, of which 32 cases (52 eyes) were cortical cataract, 18 cases ( 33 eyes ) were nuclear cataract, 23 cases ( 35 eyes ) were posterior subcapsular cataract, and 40 normal persons ( 40 eyes ) were as the normal group. The full-eye corneal astigmatism and total astigmatism were observed in all those enrolled. The contrast sensitivity of different perspective was checked by automatic glare contrast sensitivity tester.RESULTS: The corneal astigmatism and full eye total astigmatism in the cortical cataract group, nuclear cataract group and the posterior capsule cataract group was significantly higher than that in the normal group( P0. 05). The contrast sensitivity in the cortical cataract group, nuclear cataract group and posterior subcapsular cataract group in the whole band were significantly lower than the normal group (P<0. 05). The contrast sensitivity of posterior subcapsular cataract group in the whole band was significantly lower than cortical cataract groups and nuclear cataract group(P<0. 05).CONCLUSlON: lntraocular scatter light and contrast sensitivity joint inspection can effectively evaluate the visual quality of cataract patients, which lead to early treatment.