Posterior capsular opacification evaluation through contrast sensitivity defocus curves with two multifocal intraocular lenses of similar material

Analysis of the visual function with the continuous transitional focus intraocular lens Precizon Presbyopic

PURPOSE

To evaluate the clinical outcomes of a refractive multi-segmented continuous transitional focus intraocular lens (IOL), analyzing the potential influence of patient pupil dynamics on these outcomes.

METHODS

Retrospective consecutive case series study enrolling 40 eyes (20 patients, 47-81 years) implanted with the Precizon Presbyopic IOL (Ophtec BV). The following clinical outcomes were analyzed during a mean follow-up of 12.1 months (2-24 months): visual acuity, refraction, contrast sensitivity (CS) under photopic and mesopic conditions, binocular defocus curve and evaluation of the perception of disturbing visual symptoms with a validated questionnaire.

RESULTS

Mean binocular uncorrected distance (UDVA), distance-corrected intermediate (DCIVA), uncorrected near (UNVA) and distance-corrected near visual acuities (DCNVA) were -0.09 ± 0.07, 0.04 ± 0.05, 0.17 ± 0.12, and 0.15 ± 0.10 logMAR, respectively. In the binocular defocus curve, mean distance-corrected visual acuity was over 0.20 logMAR for defocus levels from +1.50 to -3.00 D. No significant correlations of photopic pupil diameter with postoperative visual data were found (-0.165 ≤ r ≤ 0.192, p ≥ 0.235). Moderate correlations of mesopic pupil size were found with visual acuities for the defocus levels of -2.50 (r = 0.454, p = 0.003), -3.00 (r = 0.609, p < 0.001), -3.50 (r = 0.519, p < 0.001), and -4.00 D (r = 0.403, p = 0.010). Only significant differences were found between mesopic and photopic CS for 12 cycles/degree (p = 0.010). No cases of severe glare or halos were detected. In contrast, 10% of patients referred the severe perception of starbursts postoperatively. Full spectacle independence was referred by almost all patients (90%).

CONCLUSIONS

The IOL demonstrates effective visual restoration at various distances, characterized by high levels of visual quality and minimal dependence on pupil dynamics.

One-year follow-up of a multifocal intraocular lens with optimized elevated phase shift

PURPOSE

To evaluate the standard outcomes of a multifocal intraocular lens (mIOL) with optimized elevated phase shift (EPS).

SETTING

Qvision, Ophthalmology Department, VITHAS Almería, Spain.

DESIGN

Retrospective observational.

METHODS

41 patients, consecutively operated on cataracts or refractive lens exchange with the implantation of the Liberty 640PM (EPS 2.0) and followed during 12 months, were included in the analysis. Retrieved variables were visual acuities at far, intermediate, and near distances; defocus curves (VADC); and prediction error of 4 formulas optimized for IOLMaster 500 and Pentacam AXL Wave. Patient-reported outcomes were also obtained for assessing spectacle independence, satisfaction, bothersome to dysphotopsia, difficulties in daily life tasks, and decision to be operated with the same mIOL.

RESULTS

The median monocular efficacy with best distance correction was 0, 0.1, and 0.1 logMAR at far, intermediate, and near distances, respectively, with patients achieving binocularly a median of 0 logMAR at the 3 distances. VADC showed a depth of field of 3 diopters (D) above 0.2 logMAR with a median increase of 0.07 logMAR from -1.5 to -2.5 D. Complete spectacle independence was achieved at far distance, whereas 97.6% and 85.4% was achieved at intermediate and near distances, respectively. 7.3% of patients were bothered by dysphotopsia, and 92.6% of patients were likely to be operated again.

CONCLUSIONS

EPS 2.0 restored patients' vision in the full range of the depth of field with a nearly monotone decrease of visual performance from far to near, achieving high rates of spectacle independence at all distances and with low positive dysphotopsia rates ( ClinicalTrials.gov Identifier: NCT05735990).

Objective cataract grading methods and expected contrast sensitivity reestablishment with multifocal intraocular lenses

PURPOSE

To determine the cut-off points for age and metrics provided by cataract grading objective systems for which a reestablishment in contrast sensitivity (CS) is expected after multifocal intraocular lens (MIOL) implantation.

METHODS

One hundred seven subjects were included in this retrospective analysis carried out during the screening for presbyopia and cataract surgery. Monocular distance corrected contrast sensitivity defocus curve (CSDC) and visual acuity were measured, and crystalline lens sclerosis was graded with three objective metrics: Ocular Scatter Index (OSI), Dysfunctional Lens Index (DLI) and Pentacam Nucleus Staging (PNS). A CS value of 0.8 logCS at far distance, following published literature on this matter, was selected to compute the cut-off that maximized the detection of eyes exceeding this value at the preoperative screening, either for age or objective metrics.

RESULTS

The CDCS showed a stronger correlation than CDVA with objective grading methods, whereas all objective metrics were significantly correlated between them (p < 0.05). The cut-offs for age, OSI, DLI and PNS were ≤ 62, ≤ 1.25, ≥ 7.67 and ≤ 1, respectively. The OSI provided the highest area under the receiver operating characteristic curve (0.85) followed by the age (0.84), DLI (0.74) and PNS (0.63).

CONCLUSIONS

Surgeons conducting clear lens exchange should communicate the possible distance CS loss after surgery with MIOL implantation according to the previous described cut-offs points. Age in combination with any cataract grading objective system is recommended to detect possible inconsistencies.

Approach to the design of different types of intraocular lenses based on an improved sinusoidal profile

An approach is presented to design different types of Intraocular lenses (IOLs) with a uniform optimization algorithm. An improved sinusoidal phase function is proposed to realize adjustable energy allocations in different diffractive orders according to the design aims. By setting specific optimization goals, different types of IOLs can be designed using the same optimization algorithm. With this method, bifocal, trifocal, extended-depth-of-focus (EDoF), and mono-EDoF IOLs are successfully designed and their optical performance under monochromatic and polychromatic light is evaluated and compared with their commercial counterparts. The result shows that most of the designed IOLs, even though they don't have any multi-zones or combination of diffractive profiles, have superior or comparable performance to their commercial counterparts in terms of optical performance under monochromatic light. The result demonstrates the validity and reliability of the approach proposed in this paper. With this method, the development time of different types of IOLs could be reduced considerably.

Geometric-phase intraocular lenses with multifocality

We demonstrate a new type of multifocal and extended depth of focus (EDOF) intraocular lenses (IOLs) embedding μm-thin geometric phase (GP) lens layers. As an emerging approach for lens phase design, the GP modulated IOLs outperform conventional diffractive IOLs in multifocality while completely avoiding the clinically undesirable demand for additional surface patterns to standard monofocal IOL designs. The number of foci and light splitting ratio of the GP IOLs are adjusted by changing the number of stacked GP layers and the thickness of each layer. Bifocal and trifocal GP IOLs are fabricated by radial alignment of anisotropic orientation in UV-curable liquid crystal polymers. After characterizing the defocus image and modulation transfer function of the GP IOLs, it is expected that GP IOLs will alleviate the most common problems associated with multifocal and EDOF IOLs, blurred vision and photic phenomena caused by light scattering and posterior capsule opacification.

Early patient-reported outcomes of cataract surgery with implantation of the trifocal liberty 677MY intraocular lens: A pilot study

PURPOSE

To report our first clinical and patient-reported outcomes in the early postoperative period with a new model of trifocal diffractive intraocular lens (IOL).

METHODS

Pilot prospective analysis of the results of 26 eyes of 13 patients (age, 44-79 years) undergoing cataract surgery with implantation of the trifocal diffractive IOL Liberty 677MY (Medicontur Medical Engineering Ltd., Zsámbék, Hungary). The following clinical outcomes were evaluated during the first postoperative month: measurement of distance, intermediate and near visual acuity, binocular defocus curve, and level of spectacle independence, patient satisfaction, perception of photic phenomena, and difficulty in performing several vision-related daily tasks by means of a questionnaire.

RESULTS

Mean binocular LogMAR uncorrected distance, intermediate and near visual acuities were -0.03 ± 0.13, 0.21 ± 0.16, and 0.16 ± 0.09, respectively. Furthermore, 100.0%, 84.6% and 92.3% of patients achieved a binocular corrected distance, distance-corrected intermediate and distance-corrected near visual acuity of 20/32 or better, respectively. In the defocus curve, visual acuities were better than 0.2 logMAR for defocus levels between +1.00 and -3.00 D. Spectacle independence was referred by all patients, with any of them reporting dissatisfaction with the outcome of the surgery. The postoperative vision did not lead to difficulties in the daily life in 92.3% of patients. Bothersome halos, glare or starbursts were only reported by only 7.7% of patients.

CONCLUSIONS

The trifocal IOL evaluated provides a successful visual rehabilitation with minimal photic phenomena associated, leading to high levels of spectacle independence and patient satisfaction.

The Influence of Angle Alpha, Angle Kappa, and Optical Aberrations on Visual Outcomes after the Implantation of a High-Addition Trifocal IOL

The aim of our investigation was to examine the possible correlations between optical aberrations, angle kappa, angle alpha, and visual outcomes following cataract surgery. In total, 56 eyes of 28 patients were implanted with the Liberty 677MY trifocal intraocular lens (IOL). Pre- and postoperative higher-order aberrations, coma, astigmatism, angle alpha, and angle kappa were registered, along with uncorrected and corrected visual acuities at multiple distances. Visual acuity and contrast sensitivity defocus curves were plotted, and the areas under the curve were calculated 1 and 3 months postoperatively. Excellent visual outcomes were found at all distances. Patients reported low levels of dysphotopsia, and 96.4% of patients achieved complete spectacle independence. While angle kappa significantly decreased during cataract surgery (p = 0.0007), angle alpha remained unchanged (p = 0.5158). Angle alpha correlated with postoperative HOAs and had a negative impact on near vision (p = 0.0543). Preoperative corneal HOA and coma had a strong adverse effect on future intermediate and near vision. Residual astigmatism significantly affected postoperative intermediate vision (p = 0.0091). Our results suggest that angle kappa is not an optimal predictive factor for future visual outcomes, while angle alpha and the preoperative screening of optical aberrations might help patient selection prior to multifocal IOL implantation.