To Investigate Visual Quality And Binocular Vision After Implantation Of Symfony With EDOF Intraocular Lens In Unilateral Cataract Patients

Purpose:To analyze the visual quality and binocular vision function after Symfony implantation in monocular cataract patients.Methods:A retrospective case-control study was conducted to select 34 monocular cataract patients(26 males(76.5%)and 8 females(23.5%)who underwent phacoemulsification combined with Symfony intraocular lens implantation in the Cataract Department of hospital of Jilin University from February 2021 to December 2021.The patients were followed up 6 months after surgery to measure their UDVA,UIVA,UNVA and to assess subjective visual quality by drawing single and binocular defocus curves.The Strehl Ratio(SR)and Modulation Transfer Function(MTF)was obtained by OPD-Scan III are used to evaluate the objective visual quality.The amplitude of accommodation(AMP)and near point of convergence(NPC)are measured by the phoropter,and the stereoacuity is checked by Titmus.The incidence of subjective adverse visual phenomena was assessed by completing the questionnaire related to visual function(QOV Scale).Results:1.Visual acuity: The UDVA of unilateral cataract patients implantated with Symfony intraocular lens was significantly improved compared with that before operation(P<0.05),while the UIVA and UNVA had no significant difference compared with the fellow normal eye(P>0.05).2.Defocusing curve: Both defocus curves are relatively smooth.Distant and intermediate visual acuity was good.Only the near curve decreased,but the binocular curve remained above the monocular.3.SR and MTF: There was no significant difference in SR and MTF under the 4mm pupil of the operative eye for 6 months compared with the fellow normal eye(P>0.05).4.AMP,NPC and Stereosis: the amplitude of accommodation of the binoculus was not statistically significant.The NPC is 26.78±8.69 cm,which is more than 8cm,indicating insufficient convergence capacity.Titmus was used to examine the stereopsis of the patients under natural light.The results showed that 35.3% of the patients had good stereopsis after operation,50% of that had stereopsis acuity between 63 " and 100",and 14.7% of the patients had poor stereopsis.Correlation analysis: AMP of operative eye and fellow normal eye,NPC and stereoscopic vision were correlated with age(P<0.05).With the increase of age,the AMP is lower and lower,and the ability to converge and stereopsis function is reduced.Meanwhile,stereosis was correlated with AMP and NPC(P<0.05).The larger the AMP,the smaller the stereoscopic acuity,the better the stereoscopic function;The worse the stereopsis function,the worse the patient’s ability to assemble.For patients with poor stereoscopic vision(14.7%),the convergence ability is obviously insufficient compared with other patients,and the breakdown points of the convergence near points are all over 25 cm.Although the convergence ability of other patients is also insufficient,it does not affect the recovery of stereoscopic vision.5.QoV scale:Most patients reported no obvious optical interference and binocular fatigue after surgery,such as glare,halo,difficulty focusing,etc.Some patients occasionally felt eye discomfort,and few patients often or frequently experienced the above discomfort symptoms.Conclusions:1.Symfony intraocular lens can provide patients with monocular cataract with UDVA,UIVA and UNVA similar to that in the fellow normal eye.2.The defocus curve of monocular cataract patients after Symfony implantation was continuous and smooth,and the binocular curve was better than monocular that at all defocus levels.3.As can be demonstrated from the SR and MTF,Symfony intraocular lens can enable patients with monocular cataract to obtain visual quality similar to that of the fellow normal eye.4.Symfony intraocular lens can reconstruct binocular vision for most monocular cataracts.Moreover,binocular stereoscopic function is related to age,AMP,and NPC.Patients with poor stereoscopic function after surgery have more insufficient gathering ability compared with other patients.5.Most patients with monocular cataract had no adverse vision-related symptoms after Symfony intraocular lens implantation,while few patients reported optical interference such as glare,halo and other symptoms related to visual function such as difficulty in focusing.