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Indian Journal of Ophthalmology Feb 2024To assess the photic phenomena (PP) and positive dysphotopsia in candidates for presbyopia or cataract surgery and to evaluate their relationship with cataract grading...
PURPOSE
To assess the photic phenomena (PP) and positive dysphotopsia in candidates for presbyopia or cataract surgery and to evaluate their relationship with cataract grading systems.
DESIGN
Retrospective observational.
METHODS
Monocular data for 82 subjects measured during the preoperative screening were retrospectively retrieved from our database. The evaluated variables consisted of two methods for PP measurement: light distortion index (LDI) and parameters obtained from a simulator, both of which were combined with subjective bother related to PP. The cutoff for LDI that better predicted patients passing from slightly to moderately bothersome was estimated. The relationships between LDI and the following objective cataract grading methods were also assessed: objective scatter index (OSI), dysfunctional lens index (DLI), and Pentacam Nucleus Staging (PNS).
RESULTS
LDI was the best method for measuring PP, which showed a significant correlation with the bothersome question (rho = 0.34, P = 0.002) and also with OSI (rho = 0.67, P < 0.0005), DLI (rho = -0.29, P = 0.007), and PNS (rho = 0.48, P < 0.0005). The number/percentage of patients who found it bothersome was as follows: "Not at all" (18/22%), "Slightly" (41/50%), "Moderately" (15/18.3%), and "Very" (8/9.7%). The cutoff value that predicted the transition from slightly to moderately bothersome was ≥15.20% according to LDI, which could be estimated with the following values for grading: ≥2.8 for OSI, ≤7.6 for DLI, and ≥2 for PNS.
CONCLUSIONS
Patients reporting moderately or higher bothersome levels in the preoperative period and with LDI <15.20%, <2.8 for OSI, >7.6 for DLI, and <2 for PNS might deserve special attention in the multifocal intraocular lens selection.
Topics: Humans; Multifocal Intraocular Lenses; Visual Acuity; Retrospective Studies; Lens Implantation, Intraocular; Prospective Studies; Cataract; Vision Disorders; Lenses, Intraocular; Phacoemulsification
PubMed: 38271416
DOI: 10.4103/IJO.IJO_1038_23 -
Scientific Reports Nov 2023This study investigated the influence of large-diameter multifocal contact lenses on the ocular surface, visual quality, and visual function for presbyopic adults with... (Randomized Controlled Trial)
Randomized Controlled Trial
This study investigated the influence of large-diameter multifocal contact lenses on the ocular surface, visual quality, and visual function for presbyopic adults with dry eye syndromes. The study enrolled 40-55-year-old adults with presbyopia and dry eye syndromes (DES). The subjects were randomly assigned to three groups wearing different designs of contact lenses (Proclear, SMR, and Optimum) for 6-8 h a day for two weeks. Ocular surface health, tear quality, visual quality, and visual function were measured before and after lens wear. No significant difference was observed across all three groups for the amount of conjunctival redness, blink frequency (lens on), and stereopsis vision before and after wearing. Although there seemed to be a significant declining trend for corneal staining and limbal redness, non-invasive tear break-up time (TBUT), and lipid layer thickness while lens wear, the measured values were all within the normal range. Vice-versa after lens removal, results also showed significant improvement on lipid layer thickness, blink frequency (lens off), and contact TBUT. A significant improvement was observed in the modulation transfer function (MTF) of the total area ratio after wearing contact lenses. In contrast, the MTF of the high-order aberration area ratio resulting from lens wear was lower than that of the baseline measurement. There are also significant improvements observed for SMR and Optimum regarding near visual acuity, near point of accommodation, and the subjective questionnaire (OSDI and VBP) scores. Although it is difficult to avoid a specific negative impact on the ocular surface and tear film, visual function and visual quality can still be positively improved, especially shown on larger diameter and distance-center designed multifocal contact lenses.
Topics: Humans; Adult; Middle Aged; Vision, Ocular; Contact Lenses; Dry Eye Syndromes; Presbyopia; Lipids; Tears
PubMed: 37945680
DOI: 10.1038/s41598-023-46732-6 -
Indian Journal of Ophthalmology Jul 2023To document the spectrum and magnitude of eye disorders and visual impairment in the Dongaria-a Particularly Vulnerable Tribal Group in the Rayagada district of Odisha,...
PURPOSE
To document the spectrum and magnitude of eye disorders and visual impairment in the Dongaria-a Particularly Vulnerable Tribal Group in the Rayagada district of Odisha, India.
METHODS
A door-to-door screening protocol included a record of basic health parameters, visual acuity for distance, and near and flashlight examination of the eyes. Spectacles were dispensed to those who improved; those who failed the screening were referred to fixed (primary and secondary) eye care centers.
RESULTS
We examined 89% (n = 9872/11,085) of people who consented for screening. The mean age was 25.5 ± 18.8 years; 55% (n = 5391) were female; 13.8% (n = 1361) were under-five children, and 39% (n = 3884) were 6 to 16 years. 86% (n = 8515) were illiterate. 12.4% (n = 1224) were visually impaired, of which 9.9% had early moderate VI, and 2.5% had severe VI and blindness. Uncorrected refractive error was detected in 7.5% (n = 744) and cataracts in 7.6% (n = 754); among the adults, 41.5% (n = 924/2227) had presbyopia. In children, 20% (n = 790) had vitamin A deficiency, 17% (n = 234) had global acute malnutrition, and 18% (n = 244) were stunted for their age. Almost two-thirds (62%, n = 6144) confirmed habitual intake of alcohol, and 4% (n = 389) of adults had essential hypertension. Following the screening, 43.5% (n = 837) of referred patients reported to the fixed centers, and 55% (134/243) of people advised underwent cataract surgery. Spectacles were dispensed to 1496 individuals.
CONCLUSION
Visual impairment and malnutrition are high in Dongaria indigenous community. Permanent health facilities and advocacy would improve this community's health and health-seeking behavior.
Topics: Adult; Child; Humans; Female; Adolescent; Young Adult; Male; Prevalence; Vision, Low; Blindness; Refractive Errors; Visual Acuity; Cataract
PubMed: 37417133
DOI: 10.4103/IJO.IJO_2788_22 -
Heliyon Sep 2023This study aims to evaluate the safety, biocompatibility, and functionality of a new accommodative intraocular lens (IOL) (LUZ, patent PCT/ES2016/070,813) after...
This study aims to evaluate the safety, biocompatibility, and functionality of a new accommodative intraocular lens (IOL) (LUZ, patent PCT/ES2016/070,813) after implantation in rabbit eyes. LUZ (Study) and EyeCee® plus a capsular ring (Control) were implanted in rabbits ( = 8 each) after phacoemulsification. Intraoperative follow-up, long-term clinical follow-up, and functional IOL studies were carried out periodically for up to 180 days. A macroscopic examination of the eyeballs to reveal abnormalities and determine the implant centering and a microscopic examination to semi-quantify cell and tissue response were performed. Statistical analysis of the collected data was finally achieved. During follow-up, no significant changes in the general condition nor the clinical evaluation were observed between both groups. However, Study IOL remained centered throughout the study and did not present severe complications as observed in the Control group. Functional studies did not reveal significant differences between both materials. Study showed better centering, fewer adhesions, and maintenance of an opening capsular bag compared to the Control. Local biological effects caused by Study implantation are minimal and comparable to the Control. Therefore, LUZ showed no clinical signs or histological response of adverse reaction to the implanted material, according to UNE-EN ISO 11979-5 and 10993-6. Functionality must be confirmed in another animal species with greater lens accommodation capacity than the rabbit. LUZ keeps the capsular bag open, favoring its centering and avoiding fibrosis and adherence to the bag; this allows potential accommodation of this IOL and theoretically enables the patient to focus dynamically.
PubMed: 37810139
DOI: 10.1016/j.heliyon.2023.e19604 -
BMC Ophthalmology Nov 2023By comparing the results of the new self-contained darkroom refractive screener (YD-SX-A) versus table-top autorefractor and cycloplegic retinoscopy, to evaluate the... (Comparative Study)
Comparative Study
PURPOSE
By comparing the results of the new self-contained darkroom refractive screener (YD-SX-A) versus table-top autorefractor and cycloplegic retinoscopy, to evaluate the performance of the YD-SX-A in detecting refractive error in children and adolescents and then judge whether it can be used in refractive screening.
METHODS
Cross-sectional study. 1000 participants between the ages of 6 and 18 who visited the Optometry Center of the People's Hospital of Guangxi Zhuang Autonomous Region from June to December 2022 were selected. First, participants were instructed to measure their diopter with a table-top autorefractor (Topcon KR8800) and YD-SX-A in a noncycloplegic setting. After cycloplegia, they were retinoscopy by a professional optometrist. The results measured by three methods were collected respectively. To avoid deviation, only the right eye (1000 eyes) data were used in the statistical analysis. The Bland-Altman plots were used to evaluate the agreement of diopters measured by the three methods. The receiver operating characteristic (ROC) curves was used to analysis effectiveness of detecting refractive error of YD-SX-A.
RESULTS
The average age of participants was 10.77 ± 3.00 years, including 504 boys (50.4%) and 496 girls (49.6%). When YD-SX-A and cycloplegia retinoscopy (CR) were compared in the myopia group, there was no statistical difference in spherical equivalent (SE) (P > 0.05), but there was a statistical difference in diopter spherical (DS) and diopter cylinder (DC) (P < 0.05). Comparing the diopter results of Topcon KR8800 and CR, the difference between each test value in the myopia group was statistically significant (P < 0.05). In the hyperopia group, the comparison between YD-SX-A and CR showed no statistically significant differences in the DC (P > 0.05), but there were significant differences in the SE and DS (P < 0.05). In the astigmatism group, the SE, DS, and DC were statistically different, and the DC of YD-SX-A was lower than that of CR and Topcon KR8800. Bland-Altman plots indicated that YD-SX-A has a moderate agreement with CR and Topcon KR8800. The sensitivity and specificity of YD-SX-A for detecting myopia, hyperopia and astigmatism were 90.17% and 90.32%, 97.78% and 87.88%, 84.08% and 74.26%, respectively.
CONCLUSION
This study has identified that YD-SX-A has shown good performance in both agreement and effectiveness in detecting refractive error when compared with Topcon KR8800 and CR. YD-SX-A could be a useful tool for large-scale population refractive screening.
Topics: Adolescent; Child; Female; Humans; Male; Astigmatism; China; Cross-Sectional Studies; Hyperopia; Myopia; Optometry; Presbyopia; Pupil Disorders; Refraction, Ocular; Refractive Errors; Retinoscopy; Vision Screening
PubMed: 38012552
DOI: 10.1186/s12886-023-03231-6 -
Optics Express Mar 2024Diffractive optics is a valuable technique for designing presbyopia-correcting lenses, but its effectiveness is wavelength-dependent. This study investigates the...
Diffractive optics is a valuable technique for designing presbyopia-correcting lenses, but its effectiveness is wavelength-dependent. This study investigates the spatio-chromatic alterations in visual resolution associated with diffractive multifocal lenses by using non-invasive, removable diffractive bifocal contact lenses. The study combines theoretical analysis, numerical simulation, and clinical intra-observer experiments to assess visual acuity under various lighting conditions. Results demonstrate the introduction of spatio-chromatic asymmetry and a change in visual acuity under red and blue lights, depending on the operating diffraction order employed in the lens design. The energy distribution of the diffractive contact lens studied favors resolution under red illumination at far distances and under blue illumination at near distances. These findings are consistent with computational simulations and provide insights into the visual changes induced by diffractive ophthalmic lenses.
PubMed: 38571249
DOI: 10.1364/OE.512212 -
Clinical Ophthalmology (Auckland, N.Z.) 2023The optical function of a novel refractive-diffractive trifocal intraocular lens (IOL) was tested in vitro to provide preclinical metrics that predict postoperative...
PURPOSE
The optical function of a novel refractive-diffractive trifocal intraocular lens (IOL) was tested in vitro to provide preclinical metrics that predict postoperative performance and may guide patient selection.
METHODS
Fundamental optical characteristics of a trifocal hydrophobic-acrylic IOL with a C-loop haptic configuration (AT ELANA 841P, Carl Zeiss Meditec) were assessed using a fully automated optical test device under both monochromatic and polychromatic conditions combined with increased or compensated spherical aberration (SA). The area under the modulation transfer function (MTFa) was calculated across a defocus range from +1D to -3.5D and used to simulate visual acuity (VA). A polychromatic point spread function (PSF) was employed to assess the light distribution and identify photic phenomena.
RESULTS
The highest MTFa values were obtained under monochromatic conditions using an SA-neutral corneal model. Nevertheless, after introducing SA and polychromatic light, the IOL performance remained good. Simulated VA values were 0.00 logMAR for distance, 0.1 logMAR at 100 cm, and progressively improving to 0.05 logMAR at 40 cm from the intermediate point. The light-spread analysis confirmed halos around the PSF center, which is a characteristic of trifocal technology.
CONCLUSION
AT ELANA 841P demonstrated good optical performance across various distances, independently of spectral and SA conditions, resulting in good simulated VA. Although light spread resembles standard trifocal IOLs, clinical studies are essential to confirm these laboratory results.
PubMed: 38143560
DOI: 10.2147/OPTH.S445461 -
Clinical Ophthalmology (Auckland, N.Z.) 2023To compare the clinical results achieved with the enhanced monofocal intraocular lenses (IOLs) with those of the monofocal IOL and investigate factors affecting the...
PURPOSE
To compare the clinical results achieved with the enhanced monofocal intraocular lenses (IOLs) with those of the monofocal IOL and investigate factors affecting the distance, intermediate, and near vision.
PATIENTS AND METHODS
Patients were included who underwent bilateral consecutive cataract surgeries using the same IOLs with follow-up to 1 month postoperatively. Refractions, monocular UDVA and CDVA, and binocular distance-corrected functional visual acuity at 5 meters (BDCFVA), at 66 centimeters (BDCIFVA) and at 40 centimeters (DCNVA) were assessed. Multiple regression analysis was used to assess the factors affecting binocular BDCFVA, BDCIFVA, and BDCNFVA. Subjective symptoms were assessed using the Near Activity Visual Questionnaire (NAVQ) and visual analogue scale (VAS).
RESULTS
Sixty patients (120 eyes) implanted with the Tecnis Eyhance IOL (30 patients, 60 eyes) or the Tecnis monofocal IOL (30 patients, 60 eyes) were included. The Tecnis Eyhance IOL provided significantly better binocular BDCIFVA than the Tecnis monofocal IOL in patients under 70 years of age. Multiple regression analysis showed that age was the only factor affecting distance and intermediate visual function in eyes with the Tecnis Eyhance IOL; gender, pupillary diameter, axial length, and average keratometry were not significant. There were no significant differences in subjective symptoms.
CONCLUSION
The comprehensive cohort analysis did not confirm the advantage on the intermediate vision of the Tecnis Eyhance IOL. Younger age may be an important factor to benefit from the unique optical characteristics of this IOL.
PubMed: 38146453
DOI: 10.2147/OPTH.S438599 -
Experimental Eye Research Aug 2023The mechanical properties of the crystalline lens are crucial in determining the changes in lens shape that occur during the accommodation process and are also a major...
The mechanical properties of the crystalline lens are crucial in determining the changes in lens shape that occur during the accommodation process and are also a major factor in the development of the two most prevalent age-related diseases of the lens, presbyopia and cataracts. However, a comprehensive understanding of these properties is currently lacking. Previous methods for characterizing the mechanical properties of the lens have been limited by the amount of data that could be collected during each test and the lack of complex material modeling. These limitations were mainly caused by the lack of imaging techniques that can provide data for the entire crystalline lens and the need for more complex models to describe the non-linear behavior of the lens. To address these issues, we characterized the mechanical properties of 13 porcine lenses during an ex vivo micro-controlled-displacement compression experiment using optical coherence elastography (OCE) and inverse finite element analysis (iFEA). OCE allowed us to quantify the internal strain distribution of the lens and differentiate between the different parts of the lens, while iFEA enabled us to implement an advanced material model to characterize the viscoelasticity of the lens nucleus and the relative stiffness gradient in the lens. Our findings revealed a pronounced and rapid viscoelastic behavior in the lens nucleus (g = 0.39 ± 0.13, τ = 5.01 ± 2.31 s) and identified the lens nucleus as the stiffest region, with a stiffness 4.42 ± 1.20 times greater than the anterior cortex and 3.47 ± 0.82 times greater than the posterior cortex. However, due to the complex nature of lens properties, it may be necessary to employ multiple tests simultaneously for a more comprehensive understanding of the crystalline lens.
Topics: Animals; Swine; Elasticity Imaging Techniques; Finite Element Analysis; Lens, Crystalline; Accommodation, Ocular; Lens Nucleus, Crystalline
PubMed: 37385534
DOI: 10.1016/j.exer.2023.109558 -
Journal of Cataract and Refractive... Jun 2024To evaluate subjective and objective outcomes after combined implantation of an extended depth-of-focus (EDOF) intraocular lens (IOL) and a combined technology...
PURPOSE
To evaluate subjective and objective outcomes after combined implantation of an extended depth-of-focus (EDOF) intraocular lens (IOL) and a combined technology multifocal lens (CT-IOL).
SETTING
2 clinical practices (Carolina Eyecare Physicians, Center For Sight) in the United States.
DESIGN
Prospective, unmasked, multicenter, nonrandomized bilateral eye study.
METHODS
Patients interested in reducing their dependence on spectacles were implanted with an EDOF IOL in the dominant eye and a CT-IOL in the nondominant eye. Refractive and visual acuity (VA) data at various distances (4 m, 66 cm, 40 cm, and 33 cm) were collected 3 months postsurgery, along with the distance-corrected binocular defocus curve and responses to questionnaires related to spectacle independence, visual disturbances, and overall visual function.
RESULTS
Data from 37 participants were analyzed. The distance-corrected binocular defocus curve showed a mean VA better than 0.1 logMAR (20/25) at all vergences from +1.00 to -2.50 diopters (D). 36 participants (97%) had an uncorrected binocular VA of 0.3 logMAR or better, at all test distances. 70% of participants (26/37) reported never wearing spectacles at any distance, and 84% (31/37) were "completely" or "mostly" satisfied with their overall vision after surgery. Halos were the disturbance reported most frequently and reported as most bothersome, with difficulty driving at night the most common visual function issue. Difficulty reading was the next most reported issue. Overall eyesight was rated as "excellent" or "good" by 92% (34/37) of participants.
CONCLUSIONS
This combined EDOF/CT-IOL approach was well-tolerated by participants and provided some potential benefits relative to bilateral implantation of either lens.
Topics: Humans; Prospective Studies; Visual Acuity; Lens Implantation, Intraocular; Presbyopia; Vision, Binocular; Male; Female; Middle Aged; Aged; Refraction, Ocular; Phacoemulsification; Pseudophakia; Patient Satisfaction; Lenses, Intraocular; Surveys and Questionnaires; Multifocal Intraocular Lenses; Dominance, Ocular; Depth Perception; Prosthesis Design
PubMed: 38305420
DOI: 10.1097/j.jcrs.0000000000001412