Purpose: To analyze the incidence and outcomes of repositioning surgery to correct misalignment of several toric intraocular lenses (IOLs) after cataract surgery. Methods: In this retrospective study, patients who underwent repositioning surgery to correct misalignment of toric IOLs following cataract surgery between January 2019 and December 2021 were enrolled. The medical data on patients' age, gender, preoperative axial length, corneal astigmatism, the axis of astigmatism, IOL models, IOL axis, uncorrected distance visual acuity, residual refraction, and postoperative outcomes were analyzed. Results: Among the 1135 eyes implanted with toric IOLs at Qingdao Eye Hospital, 23 (2.026%, 23/1135) underwent repositioning surgery. Univariate analysis revealed that the incidence of repositioning surgery was significantly lower with AcrySof (0.636%, 5/786) than with ZEISS (2.959%, 5/169) and TECNIS (7.222%, 13/180) IOL platforms; The incidence of repositioning surgery with monofocal toric IOLs (1.169%, 11/941) was significantly lower than multifocal toric IOLs (6.186%, 12/194) (P<0.001); Additionally, a significant difference in age was also observed (P=0.002). Multivariate logistic regression analysis showed that IOL platform (P=0.004) and younger age (P=0.006) were independent risk factors for repositioning surgery. Conclusion: The incidence of repositioning surgery of toric IOLs after cataract surgery was 2.026%. It was linked to the IOL platform, multifocal toric IOLs, and younger age.

Purpose:To investigate the incidence of Nd:YAG capsulotomy after implantation of two types of multifocal intraocular lenses (MIOLs). Methods: This retrospective analysis included patients who had undergone cataract extraction and implanted diffractive MIOL (Acri. LISA tri 839M) or asymmetric refractive MIOL (SBL-3) from May 2016 to September 2018. They were followed up for at least 3 years. During the followup period, the relevant data of patients were kept by special person in the hospital. The rates of Nd: YAG capsulotomy and the Kaplan-Meier survival curve were used to analyze the two groups. Results: The Asymmetric Refractive MIOL group was comprised of 98 patients (121 eyes), while the Diffractive MIOL group was comprised of 99 patients (120 eyes). There were no significant differences in age, sex, or IOL power between the two groups. The Nd:YAG rate of the asymmetric refractive MIOL group and the diffractive MIOL group was 3.3% and 7.5% respectively (P = 0.15) in the first year, 14.88% and 22.5% respectively (P = 0.129) in the second year, and 21.49% and 34.17% respectively (P = 0.028) in the third year. In the first 7 months of follow-up, the two groups showed the same performance in the Nd:YAG rate. After that, there was a difference between the two groups, and the difference gradually increased. Until the 27th month of follow-up, the difference was significant (P < 0.05). What is more, there were significant differences in survival (without Nd:YAG capsulotomy)/failure (with Nd:YAG capsulotomy) functions (P = 0.0035). Conclusion:The incidence of Nd:YAG laser capsulotomy in patients with diffractive MIOLs was higher than that in patients with asymmetric refractive MIOLs.

This study compared the clinical outcomes after cataract surgery with implantation of refractive rotationally asymmetric bifocal intraocular lens (IOL) (LS-313 MF30) and apodized diffractive bifocal IOL (ReSTOR SN6AD1). Methods: This was a prospective, non-randomized, controlled study, where patients diagnosed with age-related cataracts were selected for phacoemulsification combined with bilateral IOL implantation. Based on the type of IOL voluntarily implanted, the patients were divided into two groups, ie, refractive and diffractive groups. In total, 30 cases (60 eyes) were in a refractive group, while 30 cases (60 eyes) were in diffractive group. Three months after surgery, we examined the uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA), uncorrected near visual acuity (UNVA), defocus curve, objective visual quality, and subjective questionnaire. Results: Three months after surgery, the UIVA of the refractive group (0.18 ± 0.08) logMAR was better than that of the diffractive group (0.29 ± 0.16) logMAR (P < 0.05). No significant difference in UDVA and UNVA was noted between the two groups. For a 4mm pupil diameter, the intraocular and total eye aberration, higher-order aberration (HOA), coma, spherical aberration, and trefoil in the refractive group were significantly higher than those in diffractive group (P < 0.05). The intraocular modulation transfer function (MTF), intraocular strehl ratio (SR), total eye MTF, and total eye SR in the refractive group were lower than those in diffractive group (P < 0.05). No significant difference in glare incidence, spectacle independence rate, and patient satisfaction was observed between the two groups (P > 0.05). The halos incidence in the refractive group was lower than the diffractive group (P < 0.05). Conclusion:Both bifocal IOLs obtained satisfactory UDVA and UNVA, with higher patient satisfaction. Unlike the apodized diffractive bifocal IOL, the refractive rotationally asymmetric bifocal IOL yielded slightly better UIVA, lower halos incidence, whereas the apodized diffractive bifocal IOL showed a better objective visual quality.

For solving the time fractional conservation laws with discontinuous solutions such as shock waves, current feasible methods are the implicit finite-volume TVD schemes which employ the Lax-Friedrichs fluxes corrected by the limited slopes (see e.g. [12]). However, the schemes are hard to implement when the fractional order α is close to zero since in their implementation there are still no efficient methods to solve the strongly nonlinear spacial discrete systems at discrete times. We, aiming at increasing the implementation efficiency of the schemes above, develop two multigrid methods to solve these nonlinear spacial discrete systems. Numerical tests show that both multigrid methods have good convergence for relatively larger α, and the second one has an advantage that its convergence is affected slightly when the order α decreases to zero.