| Objectives To evaluate the influence of two intraocular lens calculation methods（Barrett Toric formula and Olsen Toric formula）on the correction effect of astigmatism correction intraocular lens（Toric intraocular lens,Toric IOL）,and the accuracy of the two calculation formulas.Methods This research is a clinical prospective randomized controlled study.A total of37 patients（41 eyes）who underwent femtosecond laser-assisted cataract phacoemulsification combined with astigmatism correction intraocular lens implantation were collected from August 2020 to January 2020 in Tangshan Eye Hospital.The method using a random number table was divided into Barrett Toric formula group with 20 cases（21 eyes）and Olsen Toric formula group with 17 cases（20 eyes）.Before the operation,Pentacam AXL was used to measure the biological parameters of the eyes.The Barrett Toric formula and the Olsen Toric formula were used to plan the Toric IOL,and then the femtosecond laser-assisted phacoemulsification combined with Toric IOL implantation was performed.The patients were followed up at the four time nodes of one day,one week,one month,and three months after the operation.In each follow-up,the patient’s subjective refraction was measured by the standard logarithmic acuity chart combined with the insert method,and the patient was recorded uncorrected visual acuity（UCVA）,best corrected visual acuity（BCVA）,measured binocular intraocular pressure,and checked the axial position of the patient’s Toric IOL under a slit lamp.The patient’s error of refractive astigmatism（ERA）is the difference between the actual residual astigmatism obtained by subjective refractive power after the operation and the estimated residual astigmatism obtained by the calculator.Compare the error magnitude（EM）and the error vector（EV）of the residual astigmatism after using the two calculation formulas.Results The absolute value of the error of the ERA of the Barrett Toric formula group at one day,one week,one month,and three months after operation were（0.227±0.228）D,（0.240±0.215）D,（0.285±0.282）D,（0.303±0.329）D;Olsen Toric formula group is（0.131±0.121）D,（0.087±0.071）D,（0.105±0.106）D,（0.136±0.104）D,except for one day after operation,other time periods There were statistical differences between the two groups（P<0.05）.The vector errors of the overall ERA of the Barrett Toric formula group were（0.280±0.244）D,（0.281±0.177）D,（0.350±0.287）D,（0.372±0.381）D on one day,one week,one month,and three months after operation;Olsen Toric formula group were（0.192±0.120）D,（0.189±0.165）D,(0.161±0.149D,（0.159±0.111）D,after comparison,it was found that the difference between the two groups at one month and three months after surgery was statistically significant（P<0.05）.After the EV of the Barrett Toric formula group and the Olsen Toric formula group were decomposed according to the vector,the absolute values of XEV and YEV were compared.There was no statistically significant difference between the two groups at one day after operation.One week after operation were（0.203±0.165）D and（0.078±0.067）D,one month after operation were（0.206±0.185）D and（0.070±0.055）D,three months after operation were（0.209±0.264）D and（0.080±0.082）D,there were statistically significant differences in XEV between the two groups（P<0.05）,and there was no statistically significant difference in YEV at each time point（P>0.05）.Conclusions Using the Barrett Toric formula and Olsen Toric formula to plan femtosecond laser-assisted phacoemulsification combined with Toric IOL implantation,the astigmatism was significantly reduced,and the correction effect was better;the error magnitude and the error vector of the residual astigmatism after Olsen Toric formula were both smaller,and the effect of long-term astigmatism correction was more advantageous.the Olsen Toric formula calculates the patient’s eye parameters more accurately based on the ray tracing principle,reduces the error caused by the posterior corneal astigmatism,and was clinically worth recommended.Figure12;Table8;Reference 178... |
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