Residents Performance In Toric Intraocular Lenses Implantation – Visual And Refractive Outcomes

To evaluate the performance of trainee residents of our center in the implantation of toric intraocular (IOL) in-the-bag lenses after cataract surgery, regarding  several outcomes such as postoperative best corrected visual acuity (BCVA), refractive astigmatism (RA), pre-existing corneal astigmatism and sphero-cylindrical refractive error (SCRE) improvement in patients with pre-existing refractive and corneal astigmatism.

Department of Ophthalmology of Centro Hospitalar Universitário S. João (Porto, Portugal), a tertiary university hospital.

Retrospective analysis of 20 eyes from 19 patients with biometric corneal astigmatism of ≥1.0 diopter (D) who underwent uncomplicated phacoemulsification with implantation of ALCON® AcrySoft IQ SN6AT toric IOL of different powers, performed by residents between November 2021 and January 2022. IOL calculations were performed using optical biometry with the ZEISS IOLMaster®500 and the ALCON® online toric IOL calculator. BCVA, corneal astigmatism (by optical biometry) and SCRE (TOPCON®KR-800) were evaluated at baseline and after six weeks. All residents had performed at least 100 cataract surgeries, but less than 20 implantations of toric IOLs. Visual and refractive outcomes were compared according to the number of previous cataract surgeries.

Median BCVA increased from 0.3logMAR units(IQR0.27) at baseline to 0.08logMAR units(IQR0.19) after 6 weeks(p<0.001). Median SCRE decreased from +2.00(IQR5.37)D to +0.25 (IQR 0.78)D(p=0.003). Median RA decreased from 1.5(IQR2.5)D to 0.75(IQR0.69)d (although not statistically significant, p=0.072). Although there were no significant statistical differences found in BCVA(p=0.093), SCRE(p=0.100), RA(p=0.342) and biometric astigmatism(p=0.069) between eyes that underwent surgery performed by residents categorized according to the number of cataract surgeries(100-199(n=5); 200-299(n=5) and 300-400(n=10)), there was a tendency for better final BCVA, lower SCRE, RA and biometric astigmatism with higher numbers of previous cataract surgeries.

Despite of the relatively reduced experience in the implantation of toric IOLs among trainee residents in our center, this study demonstrated good visual outcomes concerning the correction of refractive astigmatism (not statistically, but even so clinically relevant) among young ophthalmologists. Irrespectively the number of toric IOLs implantation, experience in cataract surgery with phacoemulsification and implantation of non-toric IOL is a potential factor for greater performance in implantation of toric in-the-bag IOLs.