Intraocular Lens Design Research Articles

Silver mean sequence in extended depth of focus intraocular lenses: a comparative study of kinoform and stepwise designs

In this work, we present two new multifocal intraocular lens (MIOL) designs, both based on the silver mean kinoform diffractive lens. We demonstrate that a single aperiodic diffractive profile can be used to create two different MIOLs: one with a kinoform structure and the other with a stepwise profile. Quantitative assessment of the designs was carried out using the through focus modulation transfer function and the area under the modulation transfer function for the prediction of their visual performance. Our results show that both designs exhibit nearly identical optical performance at the design wavelength (λ = 550 nm), though their intrinsic longitudinal chromatic aberration differs significantly. Given that diffractive extended depth of focus (EDoF) intraocular lenses are prone to image degradation due to dysphotopic phenomena, we also compared the halos generated by these two designs and found notable differences in their behavior. Furthermore, under photopic conditions, the proposed lens designs demonstrated the potential to achieve visual acuity values of 0.2 logMAR or better across a vergence range from approximately 0 to 2 D. Finally, to qualitatively assess the behavior of the MIOLs, an objective experimental evaluation was conducted using an adaptive optics visual simulator in a model eye. Experimental results align with the quantitative assessment of the proposed designs.

Pre-clinical methods to evaluate photic phenomena in intraocular lenses

A new system and methodology are introduced to evaluate photic phenomena induced by different intraocular lens (IOL) technologies using a “see-through” IOL analyzer system in phakic subjects. Nineteen phakic subjects looked through the Groningen IOL Telescope type 1 (GIT1) system under different conditions. Four different IOL designs with different clinical levels of photic phenomena were evaluated by the subjects. Subjects were asked to give a subjective rating of each lens and perform a psychophysical test. The results of this study were compared to the clinical outcomes of the subjective perception of halo, glare, and starbursts of cataract patients implanted with the same IOL models. Depending on the visual test performed, a good correlation can be found between the tests performed here and the bother levels of real cataract patients. The results validate the use of this methodology to evaluate preclinical visual symptoms. The system could be a powerful tool for the design and development of new optical designs.

Visual simulation of intraocular lenses: from on-bench performance to computational and experimental validations.

This study presents a systematic method to simulate various intraocular lenses (IOLs) available in the market. Five IOLs (two trifocals, one bifocal, one enhanced monofocal, and one extended depth of focus (EDOF)) were evaluated in terms of through focus visual Strehl (TFVS) utilizing the OptiSpheric IOL PRO2 device (Trioptics GmbH). Then, the estimated TFVS (ETFVS) and the temporal coefficients necessary for temporal multiplexing were computed, and through an iterative process, the SimVis TFVS was obtained. Finally, a high-speed focimeter was used to measure the opto-tunable lens responses to the temporal profile, and the experimental SimVis TFVS was acquired. Therefore, results are analyzed in terms of ETFVS (computed from the VSR-OTF), SimVis TFVS (computed from the TCs through temporal multiplexing), and experimental SimVis TFVS (acquired from the high-speed focimeter setup). The ETFVS and the SimVis TFVS curves demonstrated excellent alignment across all IOLs with cross-correlation coefficients > 0.94. Similarly, the experimental SimVis TFVS and the SimVis TFVS curves showed high correlation with cross-correlation coefficients > 0.97 and root mean square error (RMSE) < 0.05 for each lens. We demonstrated that different IOL designs can be visually simulated using its TFVS to obtain the corresponding temporal coefficients for simulations through temporal multiplexing using the SimVis technology.

Geometry of Modern Presbyopia-Correcting Intraocular Lenses and Changes in Haptic-Capsular Bag Behavior According to Compression and Different Well Diameters: A Bench Study Using Computed Tomography.

The geometry of an intraocular lens(IOL), the design of the haptics, and the optic-haptic junction play a role in initial and long-term visual outcome after cataract surgery. Knowledge of the behavior of an implant in the capsular bag and under compression is of major importance. Our laboratory experiment analyzed in-depth the geometry of acrylic, single-piece, premium, presbyopia-correcting intraocular lenses and changes in haptic-capsular bag relationships according to capsular bag size using a range of compression well diameters. One hydrophilic (RayOne Trifocal® RAO603F) and three hydrophobic intraocular lenses (AcrySof IQ PanOptix®, Synergy DFR00V™, and AT ELANA 841P®) were scanned with computed tomography (CT) in a dry, uncompressed state for quantitative analyses of haptic and optic-haptic junction (OHJ) dimensions and qualitative assessment of geometry. In the second part of the experiment, CT was performed after sample placement into a series of compression wells (9.0, 10.0, 11.0, 11.5mm) for analyses of length of contact (LoC) between the haptics and the wells. Axial alignment and haptic-capsular bag relationships were assessed. The qualitative and quantitative evaluations highlighted differences in haptic and OHJ geometry and dimensions across the samples. The mid-zone of the optic was thickest in the hydrophilic sample (RayOne Trifocal® RAO603F) with a maximum of 0.880mm compared to the thinnest hydrophobic sample (AT ELANA 841P®) with 0.564mm. The AT ELANA 841P® showed the largest OHJ surface area (3.86mm2) and OHJ volume (0.60mm3) of the hydrophobic samples. The TECNIS Synergy DFR00V™ showed the thickest OHJ (0.51mm), while the AcrySof IQ PanOptix® showed the thinnest OHJ (0.21mm). The LoC values decreased with increasing well size for all tested samples. The AT ELANA 841P® showed the largest LoC and largest contact zones of hydrophobic samples in all wells. The laboratory experiments highlight differences in the haptics, the OHJ geometric characteristics, and behavior of samples in different well diameters. The results support the idea that specific IOL designs may have advantages or disadvantages depending on anatomical dimensions. We cannot make any classification or rating (good versus bad) for clinical practice on the basis these experimental results, as many other factors play a role. However, knowledge of IOL geometry seems important to select the best option in each individual case.

Power profile and optical performance of two extended range-of-vision intraocular lens designs.

To assess the power profile and optical performance of 2 extended range-of-vision (ERV) intraocular lenses (IOLs), TECNIS Eyhance (ICB00) and LuxSmart, and compare them with their monofocal counterpart lenses with similar platforms and materials: TECNIS 1-piece (ZCB00) and LuxGood, respectively. Optics and Optometry Faculties of Complutense University (Madrid) and Universitat Politècnica de Catalunya BarcelonaTech (Terrassa) in Spain. Laboratory investigation on optical bench. For each design, the power distribution and (fourth and sixth-order) spherical aberration (SA) across the lens aperture were measured as well as the optical performance using modulation transfer function-based metrics with through-focus evaluation. 3 nominal powers (+10.00 diopters [D], +20.00 D, and +30.00 D) and 3 pupil sizes (2.0 mm, 3.0 mm, and 4.5 mm) were considered to assess whether the base power of the lens and pupillary dynamics have an influence on the depth-of-focus extension. TECNIS Eyhance and LuxSmart IOLs had different power and SA profiles, but both designs shared a positive add power in their central region in comparison with their monofocal counterparts. LuxSmart had a greater add power while TECNIS Eyhance showed higher peak optical quality but smaller depth of focus. Differences of focus extension between the 2 ERV IOL designs are related to differences of power and SA profile. The nominal base power of the IOLs has little effect on their optical quality. However, pupil dynamics plays a key role since it determines the effective add power and optical performance of the ERV IOLs.

Intraocular aphakia correction in patients with prior keratorefractive surgery: literature review. Part 1

Introduction. An increasing number of patients with a history of keratorefractive surgeries are presenting to ophthalmologists with complaints of vision loss due to cataracts. Treating this group poses surgeons with a range of unique challenges: high demands for vision quality, complexities in selecting the appropriate intraocular lens (IOL) power calculation formula and IOL model, target refraction, as well as the need to modify cataract extraction techniques and address specific postoperative considerations. Despite advancements in the development of new IOL designs and calculation formulas, clinical and functional outcomes in this group remain inferior to those in patients without prior keratorefractive procedures. A paradigm shift is emerging, advocating for a personalized approach in the diagnosis and management of cataracts in these patients. However, discussing all aspects within a single review proved impractical, leading us to divide it into two parts. The objective of the first part of this study is to assess the specific considerations for aphakia correction in patients who have undergone keratorefractive procedures, based on literature data, while taking into account the long-term complications of refractive surgery. Additionally, this part will address the fundamental principles of the design and functionality of pseudoaccommodating intraocular lenses (IOLs). Materials and methods. A selection of over 200 peer-reviewed publications from resources such as PubMed, eLibrary, CyberLeninka, Science Direct, and Google Scholar over the past 30 years was conducted. The first part of the review includes 49 publications. This work represents an analysis of contemporary literature, reflecting the impact of keratorefractive surgeries on the successful performance of phacoemulsification with IOL implantation. Results. The findings from the first part of the analysis indicate that a detailed medical history of previously performed keratorefractive corrections – specifically their type and potential long-term complications – play a significant role in determining the surgical treatment strategy. Standard examination methods do not always fully reflect the optical characteristics of the cornea in these patients. Extended preoperative assessments, including specialized techniques such as keratotopography and keratotomography, are crucial for identifying corneal irregularities and for the subsequent selection of the type of intraocular lens (IOL) for aphakia correction in patients who have undergone keratorefractive surgeries. Studies show high effectiveness not only in using monofocal lenses but also in the potential application of pseudoaccommodating IOLs, including those with extended depth of focus and multifocal lenses. The selection of optimal formulas for IOL calculation, as well as the clinical aspects influencing refraction in the postoperative period, will be addressed in the second part of the literature review. Conclusion. The increase in the number of refractive surgeries has led to a growing population of patients with cataracts following ametropia correction. This has spurred the development of new IOL variants with extended depth of focus. However, literature data on their effectiveness in patients who have undergone keratorefractive procedures remain limited. Multicenter prospective studies are needed to evaluate new IOL models and to determine the optimal surgical strategies for this category of patients.

Refractive Outcomes After Scleral Fixation of the Carlevale Intraocular Lens.

To assess the refractive predictability of the Carlevale sutureless scleral fixation intraocular lens (IOL) (Sole-ko IOL Division) power calculation. This retrospective, non-comparative, interventional case series included patients without a capsular support having undergone sutureless scleral fixation IOL implantation in two French hospitals between October 2019 and April 2022. IOL calculation was performed with the Barrett Universal II, Hoffer Q, Holladay 1, and SRK/T formulas with constant optimization to achieve a mean arithmetic prediction error equal to zero. The main outcomes were prediction error (PE) and its standard deviation (SD-PE), the median absolute error (MedAE), the mean absolute error (MAE), and the percentage of eyes with PE within ±0.50, ±1.00 and ±2.00 diopters (D) 6 months after surgery. Thirty eyes of 30 patients were included in the study. The mean age was 66.6 years, the mean axial length was 24.31 mm, and the mean keratometry was 43.07 D. SDPE ranged from 0.73 to 0.87 D depending on the formula. MedAE ranged from 0.38 to 0.61 D, and MAE from 0.52 to 0.68 D. Between 46.7% and 56.7% of eyes were within ±0.50 D, 76.7% and 90.0% were within ±1.00 D, and 96.7% were within ±2.00 D of target equivalent. No statistically significant difference was observed between the four formulas for any outcomes. This study confirmed that the design of the Carlevale sutureless scleral fixation IOL provides satisfactory refractive results. [J Refract Surg. 2024;40(8):e527-e532.].

Combination of a monofocal and one type of extended depth-of-focus (zonal refractive) intraocular lens (COMEDI) in bilateral cataract surgery protocol: a monocentric, randomised, parallel group trial in cataract surgery

IntroductionModern intraocular lens (IOL) designs for cataract treatment can be broadly classified into three focal range categories; monofocal, extended depth-of-focus (EDOF) and multifocal IOLs.Monofocal IOLs allow spectacle independence for one...

Dynamic Purkinje Meter as a Tool for Intraocular Lens Position Measurement

Due to the increasing demands of today’s society on visual quality and patient comfort, and due to the growing interest in the implantation of new and more complex intraocular lens (IOL) designs, determining the IOL position occupies an important position in current ophthalmological practice. The dynamic Purkinje meter combines the construction of static Purkinje meters, presented in recent years, with dynamic examination of the IOL position according to the optical axis of the IOL.

Peripheral defocus of monofocal intraocular lenses.

To quantify the angular dependence of monofocal intraocular lens (IOL) power. Ophthalmic Biophysics Laboratory, Kallam Anji Reddy campus, L V Prasad Eye Institute, Hyderabad, India. Laboratory study. Experiments were performed on IOLs from 2 different manufacturers (APPALENS 207, Appasamy Associates and SN60WF, Alcon Laboratories, Inc.). IOL powers ranged from 17 to 25 diopters (D). The IOLs were mounted in a fluid-filled chamber, and the on-axis and off-axis powers were measured using a laser ray tracing system over the central 3 mm zone with delivery angles ranging from -30 to +30 degrees in 5-degree increments. The position of the best focus was calculated for each IOL at each angle. The angular dependence of IOL power was compared with theoretical predictions. Peripheral defocus increased significantly with increasing incidence angle and power. The peripheral defocus at ±30 degrees increased from 5.8 to 8.5 D when the power increased from 17.5 to 24.5 D for APPALENS 207 and from 4.9 to 7.4 D when the power increased from 17 to 25 D for SN60WF. The mean difference between the measured and theoretical tangential power at ±30 degrees was 0.50 ± 0.16 D for the APPALENS 207 and -0.40 ± 0.10 D for the SN60WF, independent of IOL power. IOLs introduce a significant amount of peripheral defocus which varies significantly with IOL power and design. Given that peripheral defocus is related to lens power, replacement of the crystalline lens (approximately 24 D) with an IOL will produce a significant difference in peripheral defocus profile after surgery.

Fabrication and performance evaluation of a design for an extended depth-of-focus intraocular lens based on an improved sinusoidal profile.

This study presents the fabrication and evaluation of a sinusoidal extended depth-of-focus (EDoF) intraocular lens (IOL) based on our previously proposed design approach. The power, through-focus MTF, and surface profile were measured using commercial instruments. Through-focus images of a United States Air Force (USAF) 1951 resolution target formed by the fabricated IOL were compared with Symfony and AR40E under monochromatic and polychromatic light using optical bench testing. Simulations assessed visual acuity (VA) of a pseudophakic model eye with the EDoF IOL, including evaluation of tilt and decentration effects. Results indicate that the base power, add power, and the through-focus MTF@50 lp/mm of the fabricated IOL at a 3 mm pupil size align with the design specifications. The extended-depth-of-focus and imaging performance for the far vision of the fabricated IOL under both monochromatic and polychromatic light conditions at a 3.0 mm pupil diameter is comparable to that of Symfony. In addition, the fabricated IOL exhibits a similar extended-depth-of-focus for three discrete wavelengths. The pseudophakic model eye with the designed EDoF IOL demonstrates a VA exceeding 0.1 logMAR within a defocus range of 2.44 D. The VA is tolerant to both IOL tilt and decentration. These findings demonstrate the promising potential of the sinusoidal EDoF IOL design for future applications in cataract surgery.

Tolerance to refractive error with a new extended depth of focus intraocular lens

PurposeTo evaluate the tolerance to refractive errors of a new purely refractive extended depth of focus (EDF) intraocular lens (IOL) using preclinical and clinical metrics.MethodsPreclinical evaluation included computer simulations of visual acuity (sVA) and dysphotopsia profile of different IOL designs (refractive EDF, diffractive EDF, multifocal, standard, and enhanced monofocals) using an appropriate eye model with and without ±0.50 D defocus and/or +0.75 D of astigmatism. Patients bilaterally implanted with a refractive EDF (Model ZEN00V) or an enhanced monofocal (Model ICB00) IOL from a prospective, randomized study were included. At the 6-month postoperative visit, uncorrected and corrected distance vision (UDVA and CDVA), visual symptoms, satisfaction and dependency on glasses were evaluated in a subgroup of patients with absolute residual refractive error of >0.25 D in one or both eyes.ResultsIn the presence of defocus and astigmatism, sVA was comparable for all except the multifocal IOL design. The refractive EDF was more tolerant to myopic outcomes and maintained a monofocal-like dysphotopsia profile with defocus. Binocular logMAR UDVA was −0.03 ± 0.08 for ZEN00V and −0.02 ± 0.11 for ICB00. 100% ZEN00V and 97% ICB00 patients did not need glasses and were satisfied with their distance vision. Monocular CDVA, contrast sensitivity and visual symptoms were also similar between both groups.ConclusionsThe clinical outcomes of the refractive EDF IOL demonstrated high quality distance vision and dysphotopsia comparable to a monofocal IOL, even in the presence of refractive error, thus matching the design expectations of the EDF IOL.

Characterizing glare effects associated with diffractive optics in presbyopia-correcting intraocular lenses.

To objectively quantify glare of intraocular lenses (IOLs) utilizing a diffractive principle to extend visual range. To identify models with increased susceptibility to inducing glare. David J Apple Laboratory, Heidelberg, Germany. Laboratory investigation. Glare was assessed by means of straylight parameter with a standard C-Quant (Oculus GmbH) intended for 7°. In addition, two C-Quant modifications were used to test lower angles (i.e., 2.5° and 3.5°). The following IOL models were assessed: PanOptix (Alcon Inc.) and AT Lisa Tri (Zeiss Meditec), Synergy (J&J Vision), and Triumf (BVI Medical), the latter two with chromatic-aberration correction at distance. Straylight from trifocals was compared against a monofocal W-60R lens (Santen). The C-Quant test was performed through the studied IOLs via additional optical components attached to its ocular. Straylight (deg2sr-1) of the control was <1 at all tested angles, with the trifocal models showing comparable straylight at 7°. At 3.5°, Triumf's straylight increased to 15.5 ±0.6, followed by Synergy (6.2 ±1.1), PanOptix (4.1 ±0.3), and AT Lisa Tri (2.0 ±0.8). The chromatic-aberration correcting models demonstrated correspondingly high straylight (Synergy: 18.8 ±1.3; Triumf: 17.3 ±0.5) at 2.5° compared to PanOptix (4.3 ±0.4), AT Lisa Tri (2.1 ±0.1) and monofocal IOLs yielding minimal or no increase. Trifocal IOLs induced increased straylight, but it was limited to lower angles, which may cause difficulties detecting these effects using a standard clinical approach. The latest IOL designs featuring chromatic aberration correction at far-focus appear more susceptible than the established trifocals to inducing glare phenomena.

Tolerance to decentration of biaspheric intraocular lenses with refractive phase-ring extended depth of focus and diffractive trifocal designs

PurposeThis study aimed to investigate the in vitro tolerance to decentration of biaspheric intraocular lens (IOLs) with refractive phase-ring extended depth-of-focus (EDOF) and diffractive trifocal designs.MethodsThis experimental study was carried out at the Department of Optics and Optometry and Vision Science, University of Valencia, Spain. The modulation transfer function (MTF) of the ETLIO130C EDOF and the TFLIO130C trifocal IOLs (AST Products Inc., Billerica, MA, USA) were determined at different levels of decentration for a given wavelength and pupil diameter using the PMTF optical bench (Lambda-X Ophthalmics, Nivelles, Belgium). The modulation transfer function (MTF) curves, the through-focus MTF curves, and the Strehl ratios were measured at 3-mm pupil aperture for 0.25-, 0.50- and 0.75-mm decentration.ResultsThe optical design of the trifocal TFLIO130C IOL is robust to small decentrations, with virtually no change in MTF response for 0.25 mm decentration. For greater decentration levels, the MTF response is slightly reduced with increasing decentration. The ETLIO130C EDOF design is robust to decentration, as the MTF response is only minimally affected when increasing the decentration up to 0.75 mm.ConclusionsMTF responses are slightly reduced with greater levels of decentration, but the range of focus provided by both trifocal and EDOF designs are preserved. The effects for average levels of decentration reported in the literature are minimum for both IOL designs.

Comparison of Distance-Based Uncorrected Visual Acuity Based on the Optical Profile of Same Platform IOLs.

To compare and evaluate uncorrected visual acuity (UCVA) from far to near distance for four different optical designs of intraocular lenses (IOLs), developed on the same IOL platform. In a cohort of 121 patients, who underwent uncomplicated cataract surgery in Zengyo Suzuki Eye Clinic, Japan, between June 2018 and November 2023, and who received a single-piece TECNIS OptiBlue™ platform series IOL, the following four groups were established based on the IOL implant type: ZCB00V (TE), ZXR00V (SF), DFR00V (SG), and DIB00V (EH). UCVA at 5 m, 1 m, 70 cm, 50 cm, 40 cm, and 30 cm, as well as contrast sensitivity (with and without glare), was compared at one month post-operation. Regarding diffractive IOLs, patients in the SG group demonstrated significantly improved visual acuity at 5 m, 50 cm, 40 cm, and 30 cm, while those in SF group performed significantly better at 1 m. Among non-diffractive IOLs, patients in the EH group demonstrated significantly improved visual acuity scores at 1 m, 70 cm, 40 cm, and 30 cm, compared to individuals in the TE group, with comparable results between the two groups at 5 m and 50 cm. Patients in the SF and EH groups achieved similar results for visual acuity and contrast sensitivity, while those in the SG group exhibited a distinctive decrease in contrast sensitivity (with glare) relative to the other three groups. DFR00V seemingly provides excellent UCVA from near to far distances, aiming for spectacle independence, although at the potential cost of decreased contrast sensitivity compared to the other three IOL types. Furthermore, although ZXR00V and DIB00V differ lens structures, they may nonetheless provide similar visual quality and spectacle independence in daily life.

Late spontaneous posterior capsule rupture with single-piece hydrophobic acrylic intraocular lens dislocation

In this study, we described and discussed the late onset spontaneous posterior capsule rupture with intraocular lens (IOL) dislocation years after uncomplicated cataract surgery and implantation of hydrophobic acrylic IOLs. Eight patients presented with spontaneous posterior capsule rupture and IOL dislocation 5–20 years after uncomplicated phacoemulsification and IOL (AcrySof, Alcon, US) implantation. None of the patients had undergone posterior capsulotomy in the past. Four of the patients admitted habitual eye rubbing. An intact and well-centered continuous curvilinear capsulotomy edge was observed in all cases. IOLs were dislocated or displaced behind the anterior capsulotomy with a significant decrease in vision. A large rupture with a curled edge of the broken posterior capsule was visible. Dislocated IOLs were removed, and a three-piece IOL was inserted in the sulcus in six cases and suture fixated to the sclera in two cases. Improved vision was achieved in all cases. Although the mechanism underlying this late complication is unclear, habitual eye rubbing or IOL design may play a role. Further investigation is needed to prevent this complication in the future.

Changes in peripheral visual field perception after intraocular lens implantation

Aims/Purpose: To assess whether the eccentricity of the perception of objects in the peripheral visual field changes when a crystalline lens is replaced by an intraocular lens (IOL).Methods: The effect of the IOL on the eccentricity at which peripheral objects are perceived was assessed using phakic and pseudophakic versions of the same eye model. Non‐sequential ray tracing simulations were used to determine the relation between the input eccentricity at which an object was positioned in the visual field and the corresponding eccentricity at which the object was perceived by the eye in every eye model. Two different IOL designs were evaluated in the pseudophakic eye model. For each IOL design five different axial positions and seven different intrinsic powers were tested. Subsequently, the results of the pseudophakic eye models were compared to the results of the phakic model.Results: For central vision, the perceived eccentricity differed less than 1 degree between the phakic and pseudophakic models. For peripheral vision, the light rays were refracted to a more central retinal location in pseudophakic eyes than in phakic eyes, therewith shifting perceived eccentricity. The amount of the perceived shift depended on the IOL design and its axial position. The maximal shift within the evaluated pseudophakic models was 5.4 degrees towards central vision.Conclusions: IOL implantation has a minor effect on how the central visual field is perceived, but it can alter the eccentricity at which objects in the peripheral visual field are perceived by over 5 degrees. Such a shift in eccentricity can, for instance, affect how peripheral visual complaints, such as negative dysphotopsia, are experienced.

Blue Light Filtration in Intraocular Lenses: Effects on Visual Function and Systemic Health.

Blue light-filtering (BLF) intraocular lenses (IOLs) are designed to mimic the healthy natural adult crystalline lens. Studies that evaluated the relative merit of ultraviolet-only IOL design (ie, blocking wavelengths <400 nm) versus BLF IOL design (ie, filtering wavelengths ~400-475 nm in addition to blocking wavelengths <400 nm) on protection and function of the visual system suggest that neither design had a deleterious impact on visual acuity or contrast sensitivity. A BLF design may reduce some aspects of glare, such as veiling and photostress. BLF has been shown in many contexts to improve visual performance under conditions that are stressed by blue light, such as distance vision impaired by short-wave dominant haze. Furthermore, some data (mostly inferential) support the notion that BLF IOLs reduce actinic stress. Biomimetic BLF IOLs represent a conservative approach to IOL design that provides no harm for visual acuity, contrast sensitivity, or color vision while improving vision under certain circumstances (eg, glare).

Lens Diameter, Anterior Chamber Depth, and Vitreous Depth in Adult Patients: A Nigerian Study

Context: The awareness of the diversity of ocular biometry is vital in the management of glaucoma and pathologies of the lens. Aim: To establish the normal globe biometric parameters of adults in Delta State, Nigeria. Setting and Design: An observational retrospective cross-sectional study at the Radiology Department of Teaching Hospital in Delta State. A purposive sampling technique was adopted. Materials and Methods: After obtaining ethical approval, ocular biometry was conducted on 150 adult brain MRI scans (75 males and 75 females) using a digital caliper. Statistical Analysis Used: The data were analyzed and summarized in descriptive statistics. Inferential statistics were employed for comparison across gender, side, and age groups, as well as to determine the association between variables. A significance level of 5% was adopted. Results: The anterior chamber depth (ACD), vitreous depth, superoinferior (SI), and anteroposterior (AP) lens diameters were symmetrical. All the parameters lacked sexual dimorphism, while the AP and SI lens diameters significantly varied between the 10 year’s age groups (P &lt; 0.05). Age had a significant positive correlation with the AP and SI lens diameters and a negative association with ACD and vitreous length. The vitreous length had a significant positive link with the ACD and SI lens diameter (P &lt; 0.05). The AP lens diameter had a significant negative correlation with ACD and vitreous length (P &lt; 0.05). Conclusion: The normal ocular biometry obtained can be used within the studied population to help in the diagnosis of ocular conditions, management of cataracts, and the design of intraocular lenses.

Comparison of quality of life with two trifocal intraocular lenses under different lighting conditions

Aims/Purpose: To evaluate the effect of two types of trifocal intraocular lenses on the visual quality of patients undergoing cataract surgery by assessing contrast sensitivity, halo perception and subjective visual satisfaction under photopic and mesopic lighting conditions.Methods: Observational, prospective, cross‐sectional study. The study was conducted at the Hospital Universitario Sanitas la Moraleja in Madrid. The study followed the principles of the Declaration of Helsinki. The sample included 16 cataract or lensectomy patients with bilateral implantation of one of the two intraocular lenses (IOL) under study: 20 eyes implanted with FineVision and 12 eyes implanted with PanOptix. After 30 days after surgery, contrast sensitivity was measured with the CSV‐1000 test (2.5 metres) for four spatial frequencies (3, 6, 12 and 18 c/g), halo perception was assessed with the Halo.V.1 software and finally quality of life was assessed with the VF‐14 questionnaire. A p‐value &lt; 0.05 was considered a criterion for statistical significance.Results: Analysis of contrast sensitivity under photopic conditions showed significant differences greater for the FineVision lens of 0.15 log units at 3 c/g and 12 c/g frequencies between the two lenses under photopic illumination conditions (p‐value 0.034). However, there were no statistically significant differences in mesopic illumination conditions. Furthermore, there was no statistically significant difference when purchasing the perception of halos, with a p‐value (0.149). On the other hand, patients' subjective perception of quality of life scored worse in night vision (p‐value 0.023) and near vision (p‐value 0.046) when comparing the PanOptix lens and the FineVision.Conclusions: The FineVision IOL lens provides better contrast sensitivity in photopic illumination conditions than the PanOptix. However, in mesopic conditions, both IOL designs provide similar contrast sensitivity values for the far distance. On the other hand, although the lenses did not show statistically significant differences in halo perception, the FineVision shows better vision satisfaction results during night driving than the PanOptix.