| Objective:To analysis the feasibility of selectively targeting zero total postoperative spherical aberration by selecting the best fit aspheric intraocular lens (IOL) based on preoperative corneal spherical aberration of patients and to compare the vision quality after implantation of the Tecnis ZA9003 aspherical intraocular lens (IOL) between patients with a preoperative corneal spherical aberration of at least 0.33μm and patients with a preoperative corneal spherical aberration less than 0.33pm.Methods:It was a prospective case series study. The corneal spherical aberration(Z4°) with 6 mm aperture of 57 eyes (46 patients) was measured with a iTrace Visual Function Analyzer 1 day before surgery, the target postoperative total spherical aberration was set at zero. Thus, for corneal spherical aberration< +0.1μm, the Sofport Advanced Optic(AO)IOL (10 eyes) was selected; for corneal spherical aberration>+0.1μm but if<+0.235μm, the AcrySof IQ IOL(20 eyes) was selected; and for corneal spherical aberration>+0.235μm, Tecnis ZA9003 IOL (27 eyes) was selected. Aspherical IOL was implanted after phacoemulsification through a clear-cornea,3.2 mm incision without suture. Uncorrected visual acuity, best corrected visual acuity(BCVA), spherical aberration of the whole eye and internal optics (IOL) at 6 mm pupil diameter were examined at 3 months postoperatively. ANOVA and t-test were used to analyze the data at 3 months postoperatively.The corneal spherical aberration with 6 mm aperture of 60 eyes (48patients) was measured with a iTrace Visual Function Analyzer 1 day before surgery, all the patients were divided into the test group and the control group according their preoperative corneal spherical aberration of at least 0.33μm or less than 0.33μm. Tecnis ZA9003 aspherical IOL was implanted after phacoemulsification through a clear-cornea,3.2 mm incision without suture. Uncorrected visual acuity, best corrected visual acuity(BCVA), contrast sensitivity, total wavefront aberration and modulation transfer function (MTF) at six spatial frequencies were examined at 3 months postoperatively. Paired t-test were used to analyze the data at 3 months postoperatively.Results:Total postoperative ocular spherical aberration at 6 mm pupil diameter for the entire population measured+0.015±0.056μm (Sofport:0.081±0.013μm; AcrySofIQ:0.006±0.038μm; Tecnis:0.007±0.070μm). For the entire population, there was no significantly different between the predicted value and actual value of ocular spherical aberration at 6 mm pupil diameter:t=1.983, P=0.052 (Sofport:t =1.957,P=0.082; AcrySofIQ:t=0.030,P=0.976; Tecnis:t=2.031, P=0.053). For the entire population, the predictive error measured 0.014±0.044μm (Sofport: 0.006±0.012μm; AcrySofIQ:-0.000±0.037μm; Tecnis:0.027±0.052μm, F=2.626, P=0.082).The postoperative visual activity was not significantly different among the three groups (P>0.05).The postoperative spherical aberration the of eye at 6 mm pupil diameter was also larger in the test group (0.088±0.046um) than in the control group (-0.038±0.062μm)(P<0.05). The postoperative visual activity was not significantly different between the two groups (P>0.05). Patients in the test group had better contrast sensitivity than those in the cotrol group. Statistically significant differences were detected at spatial frequencies of 3.0 cycles per degree (cpd) under mesopic conditions without glare and at 1.5 cpd and 6cpd under mesopic conditions with glare(P<0.05). The values of MTF in the test group were higher than the control group at all spatial frequencies in 3.0mm and6.0 mm pupil sizes(P<0.05).Conclusion:Customized selection of aspheric IOLs based on preoperative corneal spherical aberration of patients is feasible and produces satisfactory target postoperative total spherical aberration. Targeting for a postoperative small amount of positive spherical aberration after implantation of aspherical IOL may improve the vision quality of patients.
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