Monofocal Lens Research Articles

Refractive extended depth-of-focus lens design based on periodic power profile for presbyopia correction.

Limitations of existing diffractive multifocal designs for presbyopia correction include discrete foci and photic phenomena such as halos and glare. This study aimed to explore a methodology for developing refractive extended depth-of-focus (EDoF) lenses based on a periodic power profile. The proposed design technique employed an optical power profile that periodically alternated between far, intermediate and near distances across the pupil radius. To evaluate the lens designs, optical bench testing was conducted. The impact on visual performance was assessed using a spatial light modulator-based adaptive optics vision simulator in human subjects. Additionally, the effects of pupil size change and lens decentration on retinal image quality were examined. A comparative performance analysis was carried out against a typical diffractive trifocal design and a monofocal lens. The proposed design method was found to be effective in uniformly distributing light energy across all object distances within the desired depth of focus (DoF). While trade-offs between overall image quality and DoF still exist, the EDoF lens design, when tested in human subjects, provided a continuous DoF spanning over 2.25 D. The results also revealed that the EDoF design had a slightly higher dependence on changes in pupil size and lens decentration than the diffractive trifocal design. The proposed design method showed significant potential as an approach for developing refractive EDoF ophthalmic lenses. These lenses offer a continuous DoF but are slightly more susceptible to variations in pupil size and decentration compared with the diffractive trifocal design.

Chiral Metasurface Multifocal Lens in the Terahertz Band Based on Deep Learning.

Chiral metasurfaces have garnered significant interest as an emerging field of metamaterials, primarily due to their exceptional capability to manipulate phase distributions at interfaces. However, the on-demand design of chiral metasurface structures remains a challenging task. To address this challenge, this paper introduces a deep learning-based network model for rapid calculation of chiral metasurface structure parameters. The network achieves a mean absolute error (MAE) of 0.025 and enables the design of chiral metasurface structures with a circular dichroism (CD) of 0.41 at a frequency of 1.169 THz. By changing the phase of the chiral metasurface, it is possible to produce not only a monofocal lens but also a multifocal lens. Well-designed chiral metasurface lenses allow us to control the number and position of focal points of the light field. This chiral metasurface, designed using deep learning, demonstrates great multifocal focus characteristics and holds great potential for a wide range of applications in sensing and holography.

The ideal lens for cataract patients in Thi-Qar Province

Cataract is a common age-related eye condition that affects millions of people worldwide, leading to impaired vision and decreased quality of life. The standard treatment for cataracts involves surgical removal of the cloudy lens and replacement with an intraocular lens (IOL). In recent years, significant advancements have been made in the development of ideal lenses for cataract patients, aiming to improve visual outcomes and address various visual challenges that patients may encounter post-surgery. Monofocal lenses provide excellent visual clarity at a fixed distance, either for near or distance vision, necessitating the use of glasses for other distances. Multifocal lenses, on the other hand, incorporate multiple focal points, reducing the dependency on glasses for various distances. However, they may introduce visual artifacts and reduce contrast sensitivity. EDOF lenses attempt to strike a balance, providing enhanced depth of focus while minimizing visual disturbances. Additionally, advancements in materials and technology have enabled the integration of premium features in these lenses, such as blue-light filtering, astigmatism correction, and enhanced durability, further enhancing patient satisfaction and long-term outcomes. This article also discusses the importance of personalized patient selection for specific IOL types, as individual visual needs and lifestyle preferences play a crucial role in determining the most suitable lens. Moreover, post-operative management and patient counseling are essential to manage patient expectations and maximize satisfaction with the chosen lens.

Image Contrast and Spectral Transmission in Intraocular Lenses with Nd:YAG Pits

Purpose Neodymium yttrium aluminum garnet (Nd:YAG) laser capsulotomy is considered as safe and effective method in the treatment of posterior capsule opacification. Nevertheless, side effects are described. The incorrectly adjusted focus of the laser beam during the procedure can lead to so-called YAG-pits or YAG-shots. In this experimental study, we measured spectral transmission to evaluate the image contrast and analyze the impact of YAG-pits in intraocular lenses (IOL). Methods Acrylic, foldable, one-piece IOLs with 6.0 mm optic and different material properties were studied. These included: monofocal IOLs and enhanced monofocal IOLs with water content of 0.3%, 26.0%, and 4.0% and a refractive index of 1.49, 1.46, and 1.54, respectively. All measurements were done with new, unaltered IOLs and IOLs with YAG-pits. Damage was intentionally created, performing YAG-pits (n = 7) in the central zone (3.5 mm) using a photodisruption laser (2.0mJ). All laboratory measurements were repeated: These included surface topography characterization, United States Air Force (USAF) resolution test chart analysis, spectral transmittance measurements and through focus contrast measurement. Results Significant differences were found between the unaltered lenses and lenses with defects. The YAG-pits within the optic of the IOLs decreased the image contrast and spectral transmission and changed results of USAF test images at the focal position by 62%, 57% and 54%, respectively. In all IOLs a reduction of the relative intensity of total transmitted light was observed between 450 and 700 nm wavelength. Conclusion This experimental study confirmed that the IOL image performance deteriorates with YAG-pits. The total intensity of transmitted light or transmittance (without scattering) was reduced in the wavelength between 450 and 700 nm. The contrast was significantly reduced and USAF test targets showed much worse results compared to unmodified counterparts. There was no systematic difference between monofocal and enhanced monofocal lenses. Further experiments should investigate the effect of YAG-pits on diffractive IOLs.

Cataract Surgery following Corneal Allogenic Intrastromal Ring Segments and Implantable Collamer Lens

The management of cataracts in keratoconus patients poses a challenge due to the irregular corneal shape and variability in corneal topography, which may lead to errors in determining corneal power. In this report, we present a case of a 48-year-old male with a history of keratoconus and prior Visian Implantable Collamer lenses and Corneal Allogenic Intrastromal Ring Segments procedures, who presented with a nuclear cataract in his right eye. To address this patient’s complex case, he underwent ICL explantation, cataract extraction, and intraocular lens (IOL) implantation, utilizing the Johnson & Johnson Sensar AR40 monofocal 3-piece lens with a power of −9.5. The Barrett True K formula predicted a spherical equivalent of −1.76, and at the post-operative one-month follow-up, the uncorrected distance visual acuity (UDVA) was 20/60, with pinhole improvement to 20/50. The manifest refraction was −2.50–3.25 × 145, and the best corrected visual acuity was 20/25. This case report highlights the unique challenges encountered in managing keratoconus patients with a history of prior ICL and CAIRS procedures, followed by cataract extraction. Our findings underscore the importance of a comprehensive approach in the management of progressive keratoconus and cataracts to ensure optimal outcomes.

Refractive lens exchange - who is getting it, what are they getting, how are they doing?

The purpose of this article is to provide a review of the literature on refractive lens exchange and present a retrospective analysis of 55 patients who underwent refractive lens exchange at a single practice. Our study substantiates refractive lens exchange as an important option for presbyopic patients, hyperopic patients or patients with extremely high refractive error who desire spectacle independence. Our study reveals that the refractive lens exchange population is younger than the average cataract population and their primary motivations are to resolve hyperopic or myopic refractive errors, gain spectacle independence, and address near vision loss. A variety of presbyopia-addressing intraocular lens options are available and we present our experience with multifocal, extended depth-of-focus, light-adjustable, and monofocal lenses.

Influence of isofocal intraocular lenses on objective refraction based on autorefraction and aberrometry.

To evaluate and compare the objective refractions obtained by autorefraction and aberrometry under different lighting conditions with an isofocal intraocular lens (Isopure, BVI medical, Liége, Belgium) compared to a monofocal control lens (Micropure, BVI medical, Liége, Belgium) with the same platform and material. Prospective, comparative and randomized study on patients undergoing cataract surgery and bilateral isofocal or monofocal IOL implantation. A total of 44 subjects were randomly assigned to either the isofocal group (n = 22) or the Micropure (n = 22). Manifest refraction (MR) was always performed under the same lighting conditions for all the patients. For objective refraction the autorefractor KR8800 and the aberrometer OPD-Scan III (Nidek Inc., Tokyo, Japan.) were used. For each eye included in the study, six result sets were collected: MR, AR (autorefraction measured with the autorefractor), WF-P and WF-M (Zernike-coefficients-based objective refraction, photopic and mesopic pupil size), OPD-C and OPD-M (autorefraction measured with the aberrometer in photopic and mesopic conditions). The mean sphere for MR was 0.03 ± 0.32D for the Isopure group and 0.24 ± 0.22D for the monofocal group (p = 0.013). For the Isopure group, Friedman analysis showed statistically significant differences for sphere measured with WF-P (p = 0.035), WF-M (p = 0.018) and OPD-M (p = 0.000), and SE measured with OPD-M (p = 0.004). In the Micropure lens group, the Friedman analysis showed differences for all values studied (p < 0.05). Correlation coefficients showed that AR is the objective method with the strongest correlation values for all components of refraction for both groups. The modification of the surfaces of the isofocal lens does not have a negative impact on the refraction obtained by AR compared to a standard monofocal intraocular lens.

High-Gain Millimeter-Wave Beam Scanning Transmitarray Antenna

In this article, a high-gain millimeter-wave transmitarray antenna (TAA) maintaining scanning ability is developed, integrating an array feed as the primary emitter. The work is achieved within a limited aperture area, avoiding the replacement or extension of the array. The addition of a set of defocused phases along the scanning direction to the phase distribution of the monofocal lens allows the converging energy to be dispersed into the scanning scope. The beam forming algorithm proposed in this article can determine the excitation coefficients of the array feed source, and is beneficial to improve the scanning capability in array-fed transmitarray antennas. A transmitarray based on the square waveguide element illuminated by an array feed is designed with a focal-to-diameter ratio (F/D) of 0.6. A 1-D scan with a scope of −5° to 5° is realized through calculation. The measured results show that the transmitarray can achieve a high gain, 37.95 dBi at 160 GHz, although a maximum 2.2 dB error appears compared with the calculation in the operating band of 150–170 GHz. The proposed transmitarray has been proven to generate scannable high-gain beams in the millimeter-wave band and is expected to demonstrate its potential in other applications.

Eyeglass correction: influence on the morphometric parameters of the anterior chamber and the eye hydrodynamics in presbyopes with hyperopia

The work of accommodative apparatus has a regulatory effect on the hydrodynamics of eye and it is involved in ensuring the normal outflow of intraocular fluid (IOF). Age-related weakening of accommodation leads to a deterioration in the state of hydrodynamics, and especially significant shifts are expected in patients with axial hyperopia in the anatomical boundaries of “short” eye.Purpose. To evaluate the effect of correction with progressive lenses and monofocal ones on hydrodynamic indicators and certain morphometric parameters of the anterior chamber in presbyopic patients with hyperopia under conditions of long-term habitual professional eye strain.Material and methods. 25 subjects (50 eyes) of 44–55 y. o. (mean age 47 ± 1,6 years) were examined in January-July 2022. There were 8 males and 17 females with presbyopia and hyperopia. All patients were examined at the end of their working day: the first examination was performed in the initial state without correction, the second one − under using correction with monofocal lenses (control group) or progressive ones (main group). The examination methods included visometry, autorefractometry, pneumotonometry, ultrasound biometry, computerized tonography, determination of accommodation amplitude using the push-up test, optical coherence tomography of the eye anterior segment.Results. The critic tension of hydrodynamics, the decreasing of anterior chamber depth and iridocorneal angle width were revealed in presbyopic hyperopic patients under the conditions of eye strain at a near distance without correction with eyeglasses. Using of correction with progressive lenses led to significant increasing of the accommodation amplitude (p &lt; 0,001), decreasing of IOP (p &lt; 0,001), increasing of aqueous humor outflow (p &lt; 0,001), deepening of the anterior chamber (p &lt; 0,001) and increasing of the iridocorneal angle width (p &lt; 0,001) compared to the initial state. No significant changes in these parameters were revealed in the users of monofocal lenses compared to the initial state.Conclusion. Using of progressive lenses as a permanent correction has a positive effect on ocular hydrodynamics and morphometric parameters of the anterior chamber in presbyopic hyperopes. Lack of correction in hyperopic patients of presbyopic age not only causes of eye fatigue but also can lead to disruption of hydrodynamic balance and development of glaucoma.

Use of Spectacles after Cataract Surgery.

The goal of this study was to investigate the use of spectacles in everyday life after bilateral cataract surgery with a preoperative refractive target of emmetropia in both eyes. In addition, we analyzed the total cost of spectacles and the patient's visual satisfaction at least 6 months after surgery. Patients after bilateral cataract surgery with implantation of an aspheric monofocal IOL (Tecnis 1, Johnson & Johnson) with a preoperative refractive target of emmetropia in both eyes and a documented refractive outcome were included in this prospective observational study. In a phone interview ≥ 6 months after surgery, the following items were assessed: type of spectacles purchased and overall cost, type of activity with and duration of spectacle wear, and satisfaction with the visual situation. Seventy patients were included in this study. Depending on their postoperative refraction, patients were divided into group A (n = 27) with perfect emmetropia in both eyes (i.e., spherical equivalent [SE] of ≥ - 0.25 D to ≤ + 0.25 D), group B (n = 21) with achieved emmetropia in one eye (i.e., SE of ≥ - 0.25 D to ≤ + 0.25 D) and a myopic refraction in the other eye (< - 0.25 D), and group C (n = 22) with bilateral myopic results (SE of < - 0.25 D). Overall, 84% of patients had purchased new spectacles, mostly varifocals (59%) or reading glasses (24%) at the median cost of 980 Swiss Francs (mean: CHF 912 ± 746). Despite patients' initial reasoning for their lens choice to require reading glasses only, varifocal glasses were worn for more than 50% or all of awake time by 48% of patients in group A, 43% in group B, and 68% in group C. Despite their regular spectacles use, patients' visual satisfaction was very high in all three groups. Most patients who achieve perfect bilateral emmetropia after implantation of monofocal aspheric lenses buy varifocal spectacles within 6 months, and more than half of all patients use their varifocal spectacles for more than 50% of their awakening time. The costs for such spectacles are high.

How Reliable Is Pyramidal Wavefront-Based Sensor Aberrometry in Measuring the In Vivo Optical Behaviour of Multifocal IOLs?

Cataract or refractive lens surgery, along with the implantation of multifocal intraocular lenses (MF-IOL), enables a complete range of functional far, near and intermediate vision. Refractive, diffractive and extended depth of focus (EDoF) or combination of these principles represent the technology used to obtain this multifocality. Aberrometry makes it possible to study the aberrations induced by MF-IOLs. Among the different optical principles available to measure ocular aberrations, pyramidal wavefront-based sensor (PWS) aberrometry shows the highest resolution with MF-IOLs. Retinal image quality measured by a PWS aberrometer differed significantly according to the technology of the implanted lens. Monofocal and diffractive lenses showed the highest values of far-distance retinal image quality, followed by refractive and EDoF lenses; however, retinal image quality analysed in diffractive lenses appears to be more dependent on residual refractive error. Considering this limitation, PWS-aberrometry could be used to compare diffractive lenses. Nevertheless, further studies are needed to provide additional information about the clinical retinal image quality of MF-IOLs and to help surgeons in the important preoperative selection of IOLs.

Evaluation of biometric formulas in the calculation of intraocular lens according to axial length and type of the lens

To compare the accuracy of the modern biometric formulas in cataract surgery according to axial length and lens type. It is a Cross-sectional design from 365 patients who underwent cataract surgery. The SRK/T, Hoffer Q, Haigis, and Holladay I formulas were extracted from the IOLMaster 500 biometer. Barret formulas and the Kane were obtained from the online calculator. Patients are classified according to axial length (AL) into three groups: AL ≤ 22 mm, 22 < AL < 25 mm, and AL ≥ 25 mm. In addition, implanted intraocular lenses are classified as Monofocal, extended focus, and Multifocal. There are no significant differences between the formulas. In short, the Kane formula was more accurate than the other biometric formulas. Kane and SRK/T were the most accurate in monofocal lenses, with the lowest residual refractive error. The Holladay I formula obtained the lowest mean absolute error with the highest number of eyes with minimum residual ± 0.5Dp in the multifocal lenses in the 22 < AL < 25 mm eyes. In the long AL eyes, SRK/T and Kane's obtained the lowest mean absolute error and the best percentage of eyes with ± 0.5Dp of residual refractive error. There are no significant differences between the formulas. However Kane's formula has shown high accuracy, especially in short and long eyes with monofocal lenses.

Patient reported outcomes after implementation of an enhanced depth of focus intraocular lens with low postoperative myopia

BackgroundEnhanced depth-of- focus intraocular lenses (EDOF IOL) have filled the gap between monofocal and multifocal intraocular implants with optical qualities of monofocal lenses and usually minor dysphotopsias typical for multifocal lenses. The purpose of this study was to evaluate visual outcomes after bilateral implantation of a new EDOF IOL in patients with requirements for perfect near and intermediate vision. MethodsThe study included 15 patients (29 eyes as one was amblyopic) with bilateral implantation of LUXSMART EDOF IOL (Bausch & Lomb) with a targeted myopia (between –0.25 and –0.50D) in both eyes. Monocular corrected and uncorrected visual acuity for far, intermediate and near as well as refractive outcomes were evaluated at 1, 3, 6 and 12 months after the surgery. Additionally, binocular visual acuity, contrast sensitivity and defocus curve were measured at the final follow-up visit. At 12 months’ visit patients completed a questionnaire evaluating patient satisfaction, spectacle independence and presence of dysphotopsias. ResultsBinocular uncorrected visual acuities at 12 month’s visit were 0.13 ​± ​0.16, 0.06 ​± ​0.08, 0.07 ​± ​0.09 and 0.15 ​± ​0.09 logMAR for far distance, 80 ​cm, 66 ​cm and 40 ​cm respectively. Corrected binocular visual acuities at 12 months were 0.00 ​± ​0.00, 0.05 ​± ​0.07, 0.05 ​± ​0.06, 0.13 ​± ​0.16 respectively for distance, 80 ​cm, 66 ​cm and 40 ​cm. Automated refraction spherical equivalent at 12 months’ visit stood at –0.70 ​± ​0.48D, which was 0.46D less than calculated biometric target, however spherical equivalent of subjective refraction at 12 months equaled –0.49 ​± ​0.46D, which was closer to preoperative biometric target. Defocus curve had gentle shape without peaks typical for monofocal IOLs. Binocular contrast sensitivity results were superior to average results for that age group and equaled 1.78 ​± ​0.16 logMAR without correction and 1.81 ​± ​0.13 logMAR with correction. Spectacle independence for near and intermediate distances was achieved in all patients and for far distance in 73.3% of patients. Burdensome dysphotopsias were not reported in any case. ConclusionsEDOF IOLs targeted bilaterally at low myopia can provide excellent near and intermediate visual acuity and independence of any optical correction in majority of cases. This approach can be used in selected patients who are focused on stationary activities.

Clinical outcome of diffractive multifocal lens versus monofocal lens in post-laser in situ keratomileusis patients: A retrospective, comparative study.

To compare the clinical outcomes of diffractive multifocal and monofocal lenses in post-laser in situ keratomileusis (LASIK) patients who underwent cataract surgery. This was a retrospective, comparative study of clinical outcomes that was conducted at a referral medical center. Post-LASIK patients who underwent uncomplicated cataract surgery and received either diffractive multifocal or monofocal lens were studied. Visual acuities were compared at baseline and postoperatively. The intraocular lens (IOL) power was calculated with Barrett True-K Formula only. At baseline, both groups had comparable age, gender, and an equal distribution hyperopic and myopic LASIK. A significantly higher percentage of patients receiving diffractive lenses achieved uncorrected distance visual acuity (UCDVA) of 20/25 or better (80 of 93 eyes, 86% vs. 36 of 82 eyes, 43.9%, P = 1.0 x 105) and uncorrected near vision of J1 or better (63% vs. 0) compared to the monofocal group. The residual refractive error had no significant difference (0.37 ± 0.39 vs. 0.44 ± 0.39, respectively, P = 0.16) in these two groups. However, more eyes in the diffractive group achieved UCDVA of 20/25 or better with residual refractive error of 0.25-0.5 D (36 of 42 eyes, 86% vs. 15 of 24 eyes, 63%, P = 0.032) or 0.75-1.5 D (15 of 21 eyes, 23% vs. 0 of 22 eyes, P = 1.0 x 10-5) compared to the monofocal group. This pilot study shows that patients with a history of LASIK who undergo cataract surgery with a diffractive multifocal lens are not inferior to those who receive monofocal lens. Post-LASIK patients with diffractive lens are more likely to achieve not only excellent near vision, but also potentially better UCDVA, regardless of the residual refractive error.

Peripheral Refraction and Visual Function of Novel Perifocal Ophthalmic Lens for the Control of Myopia Progression.

This study aimed to evaluate the peripheral defocus induced with a novel perifocal ophthalmic lens for myopia progression control and the potential impact on visual function. This experimental, non-dispensing crossover study evaluated 17 myopic young adults. The peripheral refraction was measured using an open-field autorefractor, at 2.50 m from the target point, in two eccentric points, 25° temporal, 25° nasal, and central vision. Visual contrast sensitivity (VCS) was measured at 3.00 m with a Vistech system VCTS 6500 in low light conditions. Light disturbance (LD) was assessed with a light distortion analyzer 2.00 m away from the device. Peripheral refraction, VCS, and LD were assessed with a monofocal lens and perifocal lens (with an add power of +2.50 D on the temporal side of the lens, and +2.00 D on the nasal side). The results showed that the perifocal lenses induced an average myopic defocus of -0.42 ± 0.38 D (p-value < 0.001) in the nasal retina, at 25° The changes induced by the lower add power in the nasal part of the lens did not induce statistically significant changes in the refraction of the temporal retina. The VCS and LD showed no significant differences between the monofocal and perifocal lenses.

Stereoacuity and Multifocal Intraocular Lenses - a Systematic Review.

Among various visual functions, stereoacuity, or the ability to perceive depth, is the most sophisticated binocular function. Many publications discuss the influence of retinal image formation by multifocal intraocular lenses on glare and contrast sensitivity, but only a few present results of testing binocular vision in patients with multifocal intraocular lenses. This article is designed to review the results of testing binocular vision in patients with multifocal intraocular lenses implanted in cataract surgery. This article was performed based on a literature review and Internet search through scientific databases such as PubMed, Scopus, Web of Science, and Google Scholar. Some reports found that patients implanted with the monofocal lens, when measured with a near addition, presented statistically significant better stereoacuity scores than those implanted with any of the multifocal intraocular lens types. When the TNO test was used for measurement, statistically significant better stereoacuity was disclosed with the refractive multifocal intraocular lens than with the diffractive-based multifocal intraocular lens design. Stereoacuity scores, even within the same types of lenses, were significantly better with the Titmus test than with the TNO test. Stereoacuity is not affected by multifocality-induced retinal blur as it is by other causes of image degradation such as small residual refractive error very early opacification of ocular media or dry eye. Multifocal intraocular lenses do not cause more functional aniseikonia than would be expected with a monofocal intraocular lens. Since stereoacuity is compromised with unilateral multifocal intraocular lens implantation bilateral implantation should be attempted.

Distance and intermediate visual acuity after a new generation monofocal intraocular lens compared with the standard monofocal intraocular lens implantation

Purpose The aim of this study was to determine the effectiveness of a novel innovative monofocal intraocular lens (Tecnis Eyhance ICB00) compared with the standard monofocal lens (Tecnis-1-piece ZCB00) in terms of contrast sensitivity, postoperative refraction, intermediate visual acuity (VA), and uncorrected and best-corrected distance VA. Patients and methods This prospective comparative interventional clinical study was conducted from January 2021 to November 2021. It included 40 eyes of 20 patients who were divided into two groups, with 10 patients each. Candidates for bilateral cataract extraction by phacoemulsification were included in this study and underwent thorough preoperative examination and postoperative evaluation at 3 months after the second eye operation. The outcome measures included intermediate and distance VA, near add, contrast sensitivity, and incidence of photic phenomena, which was evaluated using a printed questionnaire. The binocular defocus curves were analyzed. Results The study included 20 patients (seven males and 13 females). Binocular and monocular uncorrected and corrected distance VAs were statistically similar in both groups. The Eyhance group demonstrated significantly higher binocular uncorrected and corrected intermediate VA compared with the TECNIS 1-piece group (P<0.001). Defocus and contrast sensitivity values were not significantly different between the two groups. Conclusion Patients who were bilaterally implanted with the new monofocal intraocular lenses achieved significantly higher intermediate VA outcomes without affection of distance VA, with similar mean contrast sensitivity values and low incidence of photic phenomena like halo and glare compared with the standard monofocal lens.

YAG Capsulotomy Rates in Patients Following Cataract Surgery and Implantation of New Hydrophobic Preloaded Intraocular Lens in an Australian Cohort: 3-Year Results.

To assess the risk of posterior capsular opacification (PCO) following implantation of the Clareon lens. Retrospective analysis was performed for 484 consecutive eyes that had undergone phacoemulsification and implantation of a monofocal lens (CNA0T) between April 2018 and February 2020. Eyes with other ocular pathology that may affect outcomes, previous refractive surgery or eyes corrected for a near target were excluded. Incidence of PCO and YAG capsulotomy was recorded and regression analysis was performed to determine risk factors associated with PCO formation. Overall incidence of PCO following implantation of the CNA0T monofocal lens was 3.7% (18 eyes) at 1 year with 1.9% (9 eyes) undergoing YAG capsulotomy. At 3 years, 8.7% (42 eyes) had developed PCO and 4.1% (20 eyes) had undergone YAG capsulotomy cumulatively. Primary open angle glaucoma (POAG; OR = 6.53; 95% CI = 18.68, 2.28; P = 0.0005), age-related macular degeneration (AMD; OR = 2.35; 95% CI = 5.21, 1.06; P = 0.036), vitreomacular traction (VMT; OR = 7.32; 95% CI = 45.08, 1.19; P = 0.032), retinal vein occlusion (RVO; OR = 8.42; 95% CI = 38.99, 1.82; P = 0.006) and history of anti-VEGF therapy (OR = 3.22; 95% CI = 10.26, 1.01; P = 0.048) were positively associated with an increased risk of PCO. Incidence of PCO requiring YAG capsulotomy was relatively low. However, certain co-morbidities were found to increase the risk of PCO development, most significantly POAG and RVO.

Chromatic characterization of a commercially available enhanced monofocal intraocular lens

AbstractPurpose: The aim of this work is to understand the design strategy employed by the commercial Xact mono‐EDOF lens to achieve focus extension.Methods: The optical properties of the intraocular lens were measured for three wavelengths 450 nm, 550 nm, 650 nm and with polychromatic light on an optical bench complying with ISO 11979‐2, 2014 [1] for a 4.5 mm pupil. Through the Focus Modulation Transfer Functions were calculated for 50 lines per mm and Point Spread Functions were measured. The USAF test images were also captured at different vergences.Results: The Xact mono‐EDOF has an asymmetric focus for all 3 wavelengths resulting an increase in the depth of focus. On the other hand, this design shows a longitudinal chromatic aberration (LCA) of 1.41D.Conclusions: The Xact mono‐EDOF lens has a high LCA which could allow it to increase the depth of focus compared to a monofocal lens.

PD09 Comparing Long-term Costs Associated With Intraocular Lens Selection And Nd:YAG Laser Capsulotomy In The UK: A Cost-Consequence Analysis

IntroductionCataract surgery is the most frequently performed surgical procedure in the UK and posterior capsule opacification (PCO) is the most common complication post-surgery. Nd:YAG capsulotomy is the standard of care for treating PCO, although it bears a cost and is also associated with complications. The objective of this research was to estimate costs from a budget holders perspective associated with PCO related, post-cataract surgery resource use, comparing different single-piece intraocular lenses (IOLs) and utilizing results from a recently published audit of PCO incidence in the UK (n=601,084).MethodsThis research adapts the findings of the aforementioned audit to develop a cost-consequence analysis. The model is underpinned by the Nd:YAG rates of the included single-piece acrylic IOLs at 5 years. Nd:YAG related additional consultations and reported complications of the procedure were also included as variables of efficiency in the model. Estimates are presented from the perspective of a hospital setting in the UK, performing 3,000 cataract surgeries annually and extrapolated out to the broader cataract population (n=472,000). Costs were sourced from NHS Tariff documentation.ResultsAcrySof IQ was associated with lower Nd:YAG procedures and additional consultations at 5 years post-cataract surgery compared to all other single-piece monofocal acrylic lenses included in UK Audit Report. Assuming 3,000 cataract surgeries carried out annually, this translated into potential cost savings for the AcrySof IQ lens ranging from GBP 7,993 (EUR 9,379) (versus Eyecee One) to GBP 194,502 (EUR 228,243) (versus Akreos Adapt). Extrapolating to the broader population cataract patients in the UK would provide for a cost-saving estimates in the region of GBP 1.25 to GBP 30.6 million (EUR 1.47 to EUR 35.91 million).ConclusionsThis economic analysis highlights that the appropriate choice of IOL for cataract surgery, as a direct consequence of lower ND:YAG capsulotomy rates may translate into significant savings both for UK hospitals and the national healthcare system.