Comparative Study Of Visual Function In Cataract Patients After Implantation With Aspheric And Spherical Intraocular Lenses

Objective To evaluate the clinical effects of visual function in cataract patients after implantation with aspheric and spherical intraocular lenses.Methods A prospective study of 106 consecutive cases (129 eyes) were conducted. All cataract patients underwent phaocoemulsification were randomized to receive an aspheric IOL or a spherical IOL. The aspheric IOL group was divided into 4 teams due to the spherical aberration(SA) value: -0.18μmSA IOL(HOYA60AD), -0.15～-0.18μmSA IOL(STAAR KS-3AI), 0μmSA IOL(Rayner920H or Rayner970C) and inconstant SA IOL(Zeiss ZO). While the spherical IOL group had 3 types IOL to choose: Rayner570C, XLSTABI-SKY and Hexavision HQ-201. One month post-surgery, all patients were examined by slit lamp and the best corrected visual acuity(BCVA) was recorded by computer optometry. Only the patient without any complication and had a naked vision or best corrected visual acuity more than 0.8 would have the follow tests. Contrast sensitivity was analyzed by Stereo Optical-6500. The corneal aberration and whole ocular aberration were measured by Tracey Technologies iTrace at pupillary diameter 6mm. The vision function and quality of life(VF/QOL) were evaluated by questionnaires.Result The best corrected visual acuity had no significant difference among the seven IOL groups (P>0.05). Eyes with the aspheric lenses showed better contrast sensitivity at 3cpd, 6cpd and 18cpd in photopic and mesopic condition with or without glare than spherical lenses (P<0.05); better contrast sensitivity at spatial frequencies of 1.5, 3, 6, 12 and 18cpd in photopic and mesopic conditions with or without glarewere were found in inconstant SA IOL and -0.15～-0.18μmSA IOL than the other two aspheric lenses(P<0.05); the contrast sensitivity value of 3, 6, 12, 18cpd with or without glare in photopic and mesopic condition were much higher in Zeiss aspheric lenses than the Zeiss spherical ones(P<0.05); the contrast sensitivity value of 3, 6cpd with or without glare in photopic condition were much higher in Rayner aspheric lenses than Rayner spherical ones, but the opposite results were found at 18cpd in photopic condition and 3, 6, 12cpd in mesopic condition with glare(P<0.05). The mean spherical aberration in eyes with an aspheric IOL [(0.17士0.25)μm] was significantly lower than that of eyes with a spherical IOL [(0.31士0.24)μm] (P<0.05). Vision function and quality of life (VF/QOL) survey showed significant difference between the seven groups (P<0.05). Conclusions The present clinical results demonstrated that phacoemulsification with implantation of an aspheric IOL may reduce the spherical aberration and improve visual performance of pseudophakic eyes as compare to conventional spherical IOL. Especially the inconstant SA IOL and -0.18μmSA IOL implantation can improve contrast sensitivity at almost all spatial frequencies under photopic conditions and mesopic conditions and improve visual acuity.