Types Of Lenses Research Articles

Alignment error modeling and control of a double-sided microlens array during precision glass molding

Double-sided microlens arrays (DSMLAs) include combinations of two single-sided MLAs to overcome positioning errors and greatly improve light transmissivity compared to other types of lenses. Precision glass molding (PGM) is used to fabricate DSMLAs, but controlling alignment errors during this process is challenging. In this paper, a mold assembly was manufactured with a novel combination of materials to improve the alignment accuracy of mold cores during PGM by using the nonlinear thermal expansion characteristics of the various materials to improve the DSMLA alignment accuracy. By establishing a mathematical model of the DSMLA alignment error and a thermal expansion model of the mold-sleeve pair, the relationship between the maximum alignment error of the DSMLA and the mold-sleeve gap was determined. This research provides a method to optimize the mold-sleeve gap and minimize the alignment error of the DSMLA. The measured DSMLA alignment error was 10.56 μm, which is similar to the predicted maximum alignment error. Optical measurements showed that the uniformity of the homogenized beam spot was 97.81%, and the effective homogeneous area accounted for 91.66% of the total area. This proposed method provides a novel strategy to improve the performance of DSMLAs.

Contact lenses in paediatric aphakia in the Netherlands; A multicentre retrospective chart study

PurposeThe main aim of this study was to evaluate the type, parameters, loss and complications of contact lenses (CLs) in the treatment of paediatric aphakia over a 10-year period. MethodsThis retrospective multicentre chart review included the files of aphakic CL wearers under the age of 9 years old that were treated between 2008 and 2018. Patients with traumatic aphakia and scarring of the cornea were excluded. The following data were collected; demographic data, cataract type (congenital or secondary), CL type, parameters and wearing time, reason for replacement and discontinuation of the CLs, visual acuity (VA), prophylactic use of antibiotics (ABs), and complications. ResultsNinety-one aphakic children (132 eyes) were fitted with soft CLs. The median age of cataract extraction was 10.50 weeks (interquartile range (IQR) 7,15) in the congenital cataract group and 112 weeks (IQR 41,285) in the secondary cataract group. At the initial fitting a silicone elastomer CL was fitted in 86 % and a silicone hydrogel CL in 12 %, the remaining 2 % were mixed CL types. The median CL power at baseline was + 29 D (IQR 25,32) and after 3 years of wear the median power had shifted significantly to + 20 D (IQR 17,26), P < 0.001. A total of 1083 extra CL replacements were needed of which 414 in the first year of wear. Of these 414 replacements almost half (46 %;n = 191) were due to loss of the CL. Complications developed in 8 (9 %) cases and 7 (8 %) patients discontinued CL wear. ConclusionThis paper confirms that paediatric aphakia can be successfully treated with soft CLs with low rates of complications and discontinuation encountered. Unscheduled CL replacements due to loss are a concern, especially in the first year, and are straining for both the care giver and medical system. Attentive care and clear information is advised during the first year of CL wear.

Mass density profiles at kiloparsec scales using the sub-millimetre galaxies magnification bias

Context. Gravitational lensing is a powerful tool for studying the distribution of mass in the Universe. Understanding the magnification bias effect in gravitational lensing and its impact on the flux of sub-millimetre galaxies (SMGs) is crucial for accurate interpretations of observational data. Aims. This study aims to investigate the magnification bias effect in the context of gravitational lensing and analyse the mass density profiles of different types of foreground lenses, including quasi-stellar objects (QSOs), galaxies, and galaxy clusters. The specific goals are to compare the lens types, assess the impact of angular resolution on the analysis, and determine the adequacy of theoretical mass density profiles in explaining the observed data. Methods. The magnification bias was estimated using the cross-correlation function between the positions of background SMGs and foreground lens samples. Stacking techniques were employed to enhance the signal at smaller angular separations, and the more precise positions from the WISE catalogue were utilised to improve positional accuracy. Four different theoretical mass density profiles were analysed to extract additional information. Results. The cross-correlation measurements revealed distinctive central excess and outer power-law profiles, with a lack of signal in the intermediate region. The lens types exhibited varying signal strengths, with QSOs producing the strongest signal and galaxy clusters showing weaker signals. The analysis of mass density profiles indicated limitations in the selected profiles’ ability to explain the observed data, highlighting the need for additional considerations. The lack of extended emission in the QSO sample suggested possible influences from close satellites along the line of sight in the other lens types. Conclusions. The study provides valuable insights into the magnification bias effect and mass density profiles in gravitational lensing. The results suggest the presence of isolated galactic halos and the importance of considering environmental factors and close satellites in future investigations. The derived masses and best-fit parameters contribute to our understanding of lensing systems and provide constraints on the nature of central galaxies. Notably, the intriguing lack of signal around 10 arcsec challenges current understanding and calls for further quantitative analysis and confirmation of the observed feature.

THE PATIENT-PHYSICIAN RELATIONSHIP AND ROLE OF EMPATHIC COMMUNICATION IN CONTACT LENS PRACTICE

Purpose: To assess the relationship between eye care practitioners and contact lens patients and todetermine how empathy is associated with patients’ overall satisfaction.&#x0D; Methods: Multilingual electronic surveys shared by email and on social media in patients’ and practitioners’ groups. Ratings were converted to a numerical scale. The scores were compared using Wilcoxon rank sum tests.&#x0D; Results: The survey had 804 responses: 68.4% were over 46 years old, and 58.1% were female. Only 770 reported the type of contact lens worn. Of all patients, 10.6% would not recommend their physician due to feeling excluded from decisions (55.3%), lack of personal interest (63.5%), no written recommendations (84%), and unmet expectations (77%). Scleral lens wearers were highly satisfied. Optometrists excelled in care, ratings, relationships, communication, symptom relief, and prevention.&#x0D; Discussion: The findings highlight the importance of empathy in eye care and its impact on patient experiences. Factors such as contact lens type, physician recommendation, and physician type can influence the level of empathy perceived by patients. Satisfaction varied based on contact lens type, with soft and scleral lens wearers reporting better experiences. Patients valued physicians who listened, explained treatments, showed empathy, and had patient-centered communication and open-ended questions. Optometrists were scored higher than ophthalmologists in several aspects.&#x0D; Conclusion: Patients, especially scleral lens patients, were generally satisfied with the services and care. Optometrists scored higher than ophthalmologists. Patients would not recommend their physicians mainly because of a lack of empathy.

Current status of contact lenses usage in Korea: A population-based cohort study 2021.

To investigate trends in contact lens usage in a nationally representative sample of the Korean population in 2021. For this retrospective study, we analyzed data of 3,601 Korean participants aged 10-59 years, from the Korea National Health and Nutrition Examination Survey (KNHANES 2021 version), who underwent eye examination, of whom 1,136 individuals (274 men and 862 women) were contact lens users. The demographic trend among Korean contact lens wearers was examined using statistical analyses to investigate the changes in their contact lens-wearing experience, duration of lens use, type of lens used, location of purchase, presence of an Eye Care Practitioner(ECP)'s prescription, lens-related ophthalmic complications, and type of lenses worn at the time of complications, according to sex. Multivariable logistic regression analysis was conducted to examine the association of each variable with the rate of complications and use of soft lenses. The average age of the contact lens users was 33.42±0.33 years, with 70.36% (weighted percentage) of users being women who used contact lenses for significantly longer periods than men (p<0.001). Additionally, only wearing of cosmetic lenses was significantly correlated with the occurrence of complications (p = 0.006), and 6.76% of users purchased lenses without a prescription. Multivariate analysis among the contact lens users revealed a significant relationship between the complication rate and female sex (p = 0.002), pre-existing eye disease diagnosed by ECPs (p = 0.0288), and duration of contact lens use (p<0.0001). We identified sex differences in contact lens usage trends in Korea. The main changes observed were an increase in middle-aged lens users and a decrease in female users compared to that in the early 2000s. In addition, contact lens complications were significantly associated with sex and pre-existing eye disease. Therefore, those wearing contact lenses for extended periods should exercise caution and consult eye care specialists in the presence of any symptoms.

Hybrid Contact Lenses in Children: a Case Series

Introduction : Refractive errors in children have experienced a significant increase in recent years. Contact lenses are a therapeutic option when spectacles can no longer provide maximum results. One of the most advanced design than suitable for children is Hybrid Contact Lenses (HCL). HCL feature a Rigid Gas Permeable (RGP) center surrounded by a soft ridge or skirt. This design enable the hard center to provide clear vision while the soft skirt offers the comfort and ease of a soft lens. However, this type of contact lens has not been widely used in Indonesia.&#x0D; Case Illustration : Three patients were prescribed HCL to correct their high refractive errors and amblyopia; 1. 5 years old female: OD: S-14.50 C-3.25x180 6/24 OS: S-12.5 C-3.50x10 6/24; 2. 5 years old female with anisometropia: OD: S-6.00 C-2.50x180 6/12 OS: S-0.75 C-2.000x170 6/6; 3. 8 years old male with pseudophakic eyes: OD: S-9.00 C-2.00x180 6/30 OS: S-8.00 C-2.00x175 6/30. Visual Acuity after 1 month of HCL average from 6/9 to 6/6 both eyes (BE).&#x0D; Discussion : In this study, we can notice several advantages of using HCL. The main outcome are significantly increased visual acuity and reduced amblyopia. HCL also has a higher comfort level compare to RGP Lenses, the soft hydrogel skirt really help the neophyte patient to ease their initial adaptation.&#x0D; Conclusion : Contact lenses are a mainstay of optical correction options for children with special refractive needs. Due to it's design and comfort, HCL is one of the most suitable contact lenses for children. Therefore, socialization and further introduction about this contact lens is needed.

Enhanced Monofocal Intraocular Lenses in Fuchs' Endothelial Dystrophy Patients: Results from Triple Descemet Membrane Endothelial Keratoplasty Procedure.

Descemet membrane endothelial keratoplasty (DMEK) is currently regarded as the most effective surgical procedure for addressing Fuchs Endothelial Corneal Dystrophy (FECD), frequently performed in conjunction with cataract surgery. In this retrospective study, we present a comparison of visual performance, clinical outcomes, and optical quality between two types of monofocal Intraocular Lenses (IOLs): one standard and one enhanced intermediate vision model, implanted in patients who underwent combined phacoemulsification and DMEK surgery. This single center comparative retrospective study was conducted at the Eye Clinic of the University of Florence (Italy) and included a total of 48 eyes of 48 patients affected by FECD and cataract. All patients underwent combined DMEK with phacoemulsification procedures. The patients' data were analyzed and divided into two groups: one group (standard group) consisted of 24 eyes that underwent phaco-DMEK with implantation of a monofocal IOL, and the second group (enhanced monofocal group) included 24 eyes that underwent phaco-DMEK with implantation of an enhanced monofocal IOL. In both groups, the following monocular visual outcomes were evaluated 6 months after surgery: Uncorrected Distance Visual Acuity (UDVA) and Best-Corrected Distance Visual Acuity (BCDVA) at 4 mts; Uncorrected Intermediate Visual Acuity (UIVA), Distance-Corrected Intermediate Visual Acuity (DCIVA) at 66 cm; Uncorrected Near Visual Acuity (UNVA) and Best Corrected Near Visual Acuity (BCNVA). Monocular defocus curves were also assessed. Furthermore, optical quality in terms of Contrast Sensitivity (CS) in photopic conditions, Higher-Order Aberrations (HOAs) at a pupil size of 5 mm. Modulation Transfer Function (MTF), Objective Scatter Index (OSI), and Strehl ratio, were also analyzed. A Patient-Reported Spectacle Independence Questionnaire was revised to evaluate spectacle independence outcomes. the two groups did not exhibit statistically significant differences in terms of UDVA, BCDVA, UNVA and BCNVA, photopic CS, HOAs, OSI, Strehl ratio, and MTF. However, in the phaco-DMEK enhanced monofocal IOL group, significantly better results were observed in terms of UIVA and DCIVA as well as a different defocus curve profile at 1.50 D, providing better defocus results at intermediate distance compared with the ZCB00 IOL. In our study, we found that enhanced monofocal lens performed favorable visual outcomes, even in cases of FECD, compared to standard monofocal IOLs. Comparable optical quality observed in the Eyhance group could allow surgeons to consider these lenses as a viable option for selected patients with FECD.

Intraocular Straylight and Multifocal Soft Contact Lens Fit With a Myopia Control Approach.

Center-distance multifocal contact lenses (MFCLs) are used to slow myopia progression. We examined the effect of two MFCLs on intraocular straylight values in myopic individuals. Twenty-five young myopic adults were enrolled and were fit with three contact lenses (Biofinity sphere, Biofinity Multifocal, and NaturalVue Multifocal) in a random order over two study visits. Pupil size (NeurOptics VIP-300, Laguna Hills, CA) and contact lens centration were measured. Right eye intraocular straylight measurements were collected (OCULUS C-Quant; Wetzlar, Germany) and compared with a spectacle trial lens. Log straylight (LogSL) values and straylight residuals were analyzed using repeated-measures analyses of variance with Tukey-corrected post hoc t -tests. The mean participant age (±SD) was 24.1±1.5 years, and right eye spherical equivalent refractive error was -3.38±1.53 DS. There was no difference in mesopic pupil size between visits ( P =0.68) and no difference in contact lens centration between lenses ( P =0.99). LogSL values differed by lens type ( P =0.004). LogSL with the spectacle trial lens was significantly greater than with each contact lens type (all P <0.05), but there were no significant differences in LogSL between the three contact lenses (all P >0.05). There was no difference between the three contact lens designs for straylight residuals ( P =0.33). Measured intraocular straylight for both MFCLs was not different than with a spherical soft contact lens. A significant increase in intraocular straylight with spectacle trial lens correction was observed compared with all contact lenses.

Influence of posterior capsule abnormalities in pediatric cataract surgery.

To report how to manage posterior capsule abnormalities (PCAs) in pediatric cataracts and evaluate the influence of PCAs during intraocular lens (IOL) optic implantation in Berger space surgeries. Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China. Retrospective case series study. Pediatric patients with PCAs who underwent cataract surgery were evaluated. A video-based analysis of the surgical interventions included the type of crystalline lens opacification, types and management of PCAs, complications during primary posterior continuous curvilinear capsulorhexis (PCCC), need for anterior vitrectomy (AV), and feasibility of IOL optic capture. There were 227 pediatric cataract surgeries performed during the study period, and 76 eyes of 66 children with PCAs were evaluated (33.5%, 76/227). Unilateral cataract with PCAs were found in 50 eyes (22.0%, 50/227) and bilateral were found in 26 eyes (11.5%, 26/227). The PCAs were posterior capsule plaque (19.8%, 45/227), posterior capsule defect (6.2%, 14/227), posterior lenticonus (3.1%, 7/227), and persistent fetal vasculature (4.4%, 10/227). In the PCA cases, primary PCCC was successful in 44.7% of the cases (34/76). An unplanned AV during the surgeries was performed in 47.4% (36) of the 76 eyes. IOL optic implantation in Berger space was achieved in 63.2% of the eyes (48/76). PCAs are often encountered during pediatric cataract surgeries, especially in unilateral cases. The presence of PCAs may complicate a primary PCCC procedure, resulting in an unplanned AV in some cases. IOL optic implantation in Berger space can also be performed fortunately with well-designed and skilled operation.

The effect of multifocal contact lenses on the dynamic accommodation step response.

To measure the dynamic accommodation response (AR) to step stimuli with and without multifocal contact lenses (MFCLs), in emmetropes and myopes. Twenty-two adult subjects viewed alternating distance (0.25D) and near (3D) Maltese crosses placed in free space, through two contact lens types: single vision (SVCL) or centre-distance multifocal (MFCL; +2.50D add). The AR level was measured along with near to far (N-F) and far to near (F-N) step response characteristics: percentage of correct responses, magnitude, latency, peak velocity and duration of step response. There was no difference between N-F and F-N responses, or between refractive groups in any aspect of the accommodation step response dynamics. The percentage of correct responses was unaffected by contact lens type. Through MFCLs, subjects demonstrated smaller magnitude, longer latency, shorter duration and slower peak velocity steps than through SVCLs. When viewing the near target, the AR through MFCLs was significantly lower than through SVCLs. When viewing the distance target with the MFCL, the focal points from rays travelling through the distance and near zones were approximately 0.004D behind and 2.50D in front of the retina, respectively. When viewing the near target, the respective values were approximately 1.89D behind and 0.61D in front of the retina. The defocus error required for accommodation control appears not to be solely derived from the distance zone of the MFCL. This results in reduced performance in response to abruptly changing vergence stimuli; however, these errors were small and unlikely to impact everyday visual tasks. There was a decrease in ocular accommodation during near tasks, which has previously been correlated with a reduced myopic treatment response through these lenses. With MFCLs, the estimated dioptric myopic defocus was the largest when viewing a distant stimulus, supporting the hypothesis that the outdoors provides a beneficial visual environment to reduce myopia progression.

Disentangling the Black Hole Mass Spectrum with Photometric Microlensing Surveys

From the formation mechanisms of stars and compact objects to nuclear physics, modern astronomy frequently leverages surveys to understand populations of objects to answer fundamental questions. The population of dark and isolated compact objects in the Galaxy contains critical information related to many of these topics, but is only practically accessible via gravitational microlensing. However, photometric microlensing observables are degenerate for different types of lenses, and one can seldom classify an event as involving either a compact object or stellar lens on its own. To address this difficulty, we apply a Bayesian framework that treats lens type probabilistically and jointly with a lens population model. This method allows lens population characteristics to be inferred despite intrinsic uncertainty in the lens class of any single event. We investigate this method’s effectiveness on a simulated ground-based photometric survey in the context of characterizing a hypothetical population of primordial black holes (PBHs) with an average mass of 30M ⊙. On simulated data, our method outperforms current black hole (BH) lens identification pipelines and characterizes different subpopulations of lenses while jointly constraining the PBH contribution to dark matter to ≈25%. Key to robust inference, our method can marginalize over population model uncertainty. We find the lower mass cutoff for stellar origin BHs, a key observable in understanding the BH mass gap, particularly difficult to infer in our simulations. This work lays the foundation for cutting-edge PBH abundance constraints to be extracted from current photometric microlensing surveys.

The Influence of Lid-Parallel Conjunctival Folds and Conjunctivochalasis on Dry Eye Symptoms with and Without Contact Lens Wear: A Review of the Literature.

Lid-parallel conjunctival folds (LIPCOF) and conjunctivochalasis (CCH) are similar conditions that seem to be related to dry eye severity. In addition, there is a lack of studies on the topic of LIPCOF and CCH on dry eye symptoms in non-contact lens and contact lens (CL) wearers. Therefore, the aim of this study is to review the relationship of LIPCOF and CCH with dry eye symptoms in non-CL and CL wearers, as well as to report the treatment of dry eye disease (DED) in non-CL and CL wearers who present LIPCOF or CCH. A literature review of full-length original studies in two databases, PubMed and Scopus, was performed. The search period included observational studies in humans published between April21, 2009 and March20, 2023. A total of 26 studies were included. The studies suggest that LIPCOF and CCH are significantly related to dry eye symptoms in non-CL and CL wearers. However, the impact of CL wear on LIPCOF and CCH may be complex and may vary depending on individual factors such as lens type, lens care regimen, and pre-existing ocular conditions. Regarding LIPCOF management, tear substitutes seem to significantly reduce LIPCOF and dry eye symptoms in non-CL wearers, while vectored thermal pulsation (VTP) and microblepharoexfoliation (MBE) are suggested as promising treatment for LIPCOF and dry eye symptoms in CL wearers. Regarding CCH management, surgical interventions may be effective in reducing CCH when medical treatments have no response. In addition, an ocular examination by slit lamp is necessary to distinguish both conditions. Tear substitutes, VTP, MBE, and fitting CLs with low coefficient of friction (CoF) seem to reduce and prevent LIPCOF. However, surgical treatment options seem to be more effective in the complete elimination of CCH. An adequate evaluation and differentiation between LIPCOF and CCH are important, and they should be considered by practitioners in managing dry eye symptoms in non-CL and CL wearers.

An epidemic of cataract surgery in Korea: the effects of private health insurance on the National Health Insurance Service.

In Korea, the National Health Insurance Service (NHIS) covers essential healthcare expenses, including cataract surgery. To address concerns that private health insurance (PHI) might have inflated the need for such procedures, we investigated the extent of the PHI-attributable increase in cataract surgery and its impact on NHIS-reimbursed expenses. This retrospective, observational study uses nationwide claims data for cataract surgery from 2016 to 2020. We examined trends in utilization and cost, and we estimated the excess numbers of (1) cataract operations attributable to PHI and (2) types of intraocular lenses used for cataract surgery in 2020. Between 2016 and 2020, a 36.8% increase occurred in the number of cataract operations, with increases of 63.5% and 731.8% in the total healthcare costs reimbursed by NHIS and PHI, respectively. Over a 5-year period, the surgical rate per 100,000 people doubled for patients aged <65 years (from 328 in 2016 to 664 in 2020). Among the 619,771 cases in 2020 of cataract surgery reimbursed by the Korean diagnosis-related group system, more non-NHIS-covered intraocular lenses were used for patients aged <65 years than ≥65 years (68.1 vs. 14.2%). In 2020 alone, an estimated 129,311 excess operations occurred, accounting for an excess cost of US$115 million. A dramatic increase in the number and cost of cataract operations has occurred over the last 5 years. The PHI-related increase in operations resulted in increased costs to NHIS. Measures to curtail the non-indicated use of cataract surgery should be implemented regarding PHI.

Analysis of the recording of Fibonacci lenses on photopolymers with 3-D diffusion model

In this work a three-dimensional diffusion model is used to model photopolymers as a recording media. This model allows us to predict the properties of the Diffractive Optical Elements (DOEs) once we recorded into the photopolymer. This model had never been tested with more complex elements, such as multifocal diffractive lenses, as presented in the following in this work. In addition, the model includes; the estimation of the refractive index modulation, the low-pass filtering effect due to the experimental optical setup, and the evolution of the transverse intensity distribution. In this way, the selection of the appropriate material characteristics depending on the intended DOE application is made possible. Specifically, an acrylamide-based PVA/AA photopolymer is simulated using the proposed model. Moreover, coverplating and index matching systems are considered together to avoid the effects of thickness variation. Furthermore, in order to compare their properties using the proposed model, we focus on Fibonacci lenses (FL), a type of bifocal lenses. This allows us to evaluate the dependence of the focii intensity on the polymerisation rate, the diffusivity parameter, low-pass filtering effect and the use of the index matching system for these lenses. This enables us to know the recording parameters in order to produce this type of multifocal diffractive lenses with higher quality and precision.

Evaporation and desalination using a solar concentrator in an agricultural complex

The purpose of the article is to study boiling and distilling water using solar concentrator, the actual application and profitability of using such a method of liquid evaporation. The use of various modern types of technologies makes it possible to purify water as efficiently as possible, while avoiding the decomposition of compounds. The different configurations of boiling by means of solar concentrator allow meeting different forms of application. Such configuration changes include different types of lenses, as well as different shapes and sizes of the solar concentrator itself, the use of mirror arrays that can be configured in such a way as to direct sunlight to one point to achieve high temperatures.

Pearls and pitfalls in IOL power calculation

Before cataract surgery with intraocular lens implantation ocular biometry is performed as a standard procedure. From the biometric measures and the individual patient requirements an appropriate lens type is selected and the lens power is calculated based on a empirical/AI based, theoretical optical, or raytracing based calculation scheme. In this talk we give an overview on the most relevant calculation strategies and discuss the advantages and drawbacks of the most commonly used IOL power calculation concepts. Some systematic errors inherent to the calculation schemes and the clinical consequences are discussed.

Comparative Analysis of Tolerance to Experimentally Induced Astigmatism with Three Types of Multifocal Intraocular Lenses.

The effect of residual astigmatism and its axis on distance and near visual acuities (VAs) with multifocal intraocular lenses (IOLs) has not been studied extensively. This study compared the tolerance to experimentally induced residual astigmatism among bifocal, trifocal, and extended depth-of-focus (EDOF) IOLs. This retrospective, comparative study included 70 eyes of 70 patients implanted with bifocal, trifocal, or EDOF IOLs. Distance and near VAs were assessed with experimentally induced astigmatism by placing positive cylindrical lenses in increments of 0.50 diopters to 2.00 diopters at 90° and 180° axes over the best distance correction. Both distance and near VAs worsened with increasing magnitudes of experimentally induced astigmatism except in the EDOF group, in which the near VA remained within a clinically acceptable limit, ie, within one line from the best corrected VA under all ranges of experimentally induced astigmatism. Furthermore, the EDOF group showed the highest astigmatic threshold for losing VA lines following experimental astigmatic induction at both distance and near. The distance VA was generally better at with-the-rule (WTR) than against-the-rule (ATR) astigmatism for all three IOL groups. On the other hand, the near VA was generally better at WTR than ATR astigmatism in the bifocal group, comparable between WTR and ATR astigmatism in the trifocal group, and generally better at ATR than WTR astigmatism in the EDOF group. The EDOF IOL demonstrated the highest tolerance to experimentally induced astigmatism at both distance and near. VA was generally less affected by WTR astigmatism than ATR astigmatism, especially at distance. We proposed the residual astigmatism thresholds for clinically acceptable VA reduction in all three IOL groups.

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.

Refractive error of canine cataract patients following implantation with three types of intraocular lenses.

To evaluate refractive state outcomes following phacoemulsification and implantation of 3 different intraocular lenses (IOLs). A prospective, randomized, controlled study was conducted on 43 client-owned dogs undergoing phacoemulsification with IOL implantation. Eyes were randomized to receive either an-vision Fo-X (n = 26), an-vision MD8 (18), or I-MED I-LENS (24) IOL. Refraction was measured 1 week, 1 month, and 3 months postoperatively using streak retinoscopy by 2 examiners masked to each other's results. Postoperative refractive outcomes were highly correlated and not significantly different between 2 examiners for all time points (r = 0.97, 0.98, and 1.00; P = .76, .94, and .98, respectively). One week postoperatively, the refractive errors (mean ± SD) for Fo-X, MD8, and I-LENS were -0.14 ± 2.02 diopters (D), 0.97 ± 2.01 D, and 0.15 ± 2.55 D, respectively. One month postoperatively, the refractive errors were 0.35 ± 2.04 D, 0.06 ± 2.41 D, and -0.82 ± 2.20 D, respectively. Three months postoperatively, the refractive errors were -0.16 ± 2.67 D, 1.60 ± 2.99 D, and 0.59 ± 1.51 D, respectively. There were no significant differences in refractive error outcomes between Fo-X, MD8, and I-LENS at 1 week, 1 month, and 3 months postoperatively (P = .16; F(df=2,66)- = 1.89). However, the Fo-X was the only IOL to yield nearly emmetropic outcomes (±0.50 D) at all 3 time points. The postoperative refractive states of dogs were not statistically different when comparing 3 types of IOLs at 3 postoperative time points, though the Fo-X was the only IOL to yield nearly emmetropic outcomes at all 3 time points.

In vitro compatibility study of a new preservative‐free multidose 0.6% bilastine eye drop formulation containing sodium hyaluronate with soft and gas rigid permeable contact lenses

Aims/Purpose: Despite many patients with allergic conjunctivitis are contact lens wearers, research on the physical compatibility of antihistamine eye drops and contact lenses is lacking. The aim of this work was to evaluate the in vitro compatibility of a new preservative‐free bilastine eye drops with the main types of contact lenses.Methods: The physical compatibility of a new preservative‐free bilastine eye drops in comparison with an isotonic saline solution, was evaluated in three types of contact lenses: hydrogel, silicone hydrogel and gas rigid permeable. Physical properties evaluated: diameter of the lens, posterior vertex power, radius of curvature, physical appearance, and spectral transmittance were characterized. For initial characterization, the lenses (n = 60) were equilibrated in a saline solution at 20–25°C for 24 h. After, 10 lenses of each type were separately immersed in either the saline solution or the bilastine formulation, both at 20–25°C, for 1 h, and then subjected to 30 wash cycles. The physical characterization was carried out after 1, 15 and 30 wash cycles, measurements performed in triplicate. Measurement methods and tolerance limits of the physical properties and general procedure and performance criteria for assessing the physical compatibility of contact lens were conducted in accordance with the guidelines (UNE‐EN ISO 18369‐3:2007; UNE‐EN ISO 18369‐2:2007; UNE‐EN ISO 11981:2013).Results: The incubation of contact lenses with the new preservative‐free bilastine eye drop formulation did not affect any of the physical properties of the lenses and the results were comparable to those exposed to the control saline solution. The physical properties of all the contact lenses tested in both conditions complied with the manufacturer's specifications and tolerance limits stablished.Conclusion: These results indicate that the new preservative‐free bilastine eye drop is physically compatible with soft and rigid gas permeable contact lens.