The comparison of visual function in cataract patients after implantation with spherical and aspheric intraocular lens

Objective To evaluate clinical effects of visual function after implantation with aspheric intraocular lens(IOL)in phacoemulsification for cataract.Methods Sixty eyes of 55 patients undergoing cataract surgery were randomly divided into two groups:thirty eyes of 25 tients received aspheric IOLs and thirty eyes of 30 patients received conventional spherical IOLs﹒At one week,one month,three months after surgery,the following investigations were performed to assess the uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),near visual acuity(NVA),contrast sensitivity,wavefront aberration and stereopsis of eyes.Results The difference of UCVA,BCVA and NVA between these two groups was not significant after sugery at one week,one month ;but the UCVA,BCVA and NVA in eyes with an aspheric IOL were obviously better than that of eyes with a spherical IOL at three months postoperatively.After one week and three months,the aspheric IOL provided significantly better contrast sensitivity at almost all spatial frequencies under photopic conditions and mesopic conditions in comparison with the spherical IOL.In these two groups,the wavefront aberration showed the significant difference after one month and three months.The differences of distance and near stereopisis with BCVA and NVA between these two groups were not significant after sugery at one month and three months.Conclusions The present clinical results demonstrated that the aspheric IOL can improve contrast sensitivity at almost all spatial frequencies under photopic conditions and mesopic conditions and decrease spherical aberration as compare to a spherical IOL.