Mesopic Conditions Research Articles

Comparison of Contrast Sensitivity between Alternating and Monocular Intermittent Exotropia

Purpose: To determine if contrast sensitivity varies between alternating and monocular intermittent exotropia.Methods: The study conducted a retrospective analysis of medical records for children aged 5-9 years with intermittent exotropia who had uncorrected visual acuity of 1.0 or better, a spherical equivalent of ± 1.50 diopters (D) or less, and anisometropia of 1.00 D or less. Patients were categorized into two groups using the cover-uncover test: an alternating group without fixation preference and a monocular group with fixation preference. Contrast sensitivity tests were performed on each eye under mesopic and photopic conditions with glare. In the alternating group, eyes were classified as right or left while in the monocular group the non-deviated eye was labeled dominant and the deviated eye was non-dominant.Results: The study included 53 patients with 31 in the alternating group and 22 in the monocular group. In the alternating exotropia group, the left eye demonstrated significantly better contrast sensitivity at 1.1 cycles per degree (cpd) under mesopic conditions (<i>p</i> = 0.043), with no significant differences noted under other conditions. In the monocular exotropia group, dominant eyes exhibited significantly better contrast sensitivity at 10.2 cpd under mesopic conditions (<i>p</i> = 0.046) and at 1.1 cpd under photopic conditions (<i>p</i> = 0.031). No significant differences were observed in the interocular contrast sensitivity between the monocular and alternating groups across all spatial frequencies under both mesopic and photopic conditions.Conclusions: Pediatric patients with monocular intermittent exotropia displayed no significant differences in contrast sensitivity between dominant and non-dominant eyes except at certain frequencies. Additionally, there were no significant interocular contrast sensitivity differences between the monocular and alternating groups suggesting that contrast sensitivity tests may not be effective for determining the dominant eye in these conditions.

Analysis of intraocular lens tilt and decentration after cataract surgery in eyes with high myopia using the anterior segment optical coherence tomography.

This retrospective study investigated the degree of intraocular lens (IOL) tilt and decentration after cataract surgery in eyes with varying degrees of myopia using the anterior segment optical coherence tomography (AS-OCT). Eyes of 76 patients were analyzed and divided into three groups: mild myopia (emmetropia to - 1.5 diopter [D], Group 1), moderate myopia (- 1.5 D to - 6.0 D, Group 2), and high myopia (over - 6.0 D, Group 3). Postoperative IOL decentration, tilt, and lens diameter were evaluated using swept-source AS-OCT under mesopic conditions without dilation eyedrop. Postoperative parameters revealed no difference in IOL tilt, but IOL decentration was significantly different among the groups, and the degree of decentration was greater in Group 3 (P = 0.007). Univariable regression analysis indicated that age, sex, preoperative uncorrected distant visual acuity, corrected distant visual acuity, intraocular pressure, spherical equivalent, preoperative anterior chamber depth and lens thickness had no influence on postoperative IOL decentration, but axial length (AL) was significantly related to IOL decentration (P = 0.001). This association was confirmed using multivariable regression analysis, establishing a significant correlation between AL and IOL decentration (P = 0.001) on AS-OCT, showing an increase in IOL decentration associated with increasing AL.

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

To evaluate the clinical outcomes of a refractive multi-segmented continuous transitional focus intraocular lens (IOL), analyzing the potential influence of patient pupil dynamics on these outcomes. Retrospective consecutive case series study enrolling 40 eyes (20 patients, 47-81 years) implanted with the Precizon Presbyopic IOL (Ophtec BV). The following clinical outcomes were analyzed during a mean follow-up of 12.1 months (2-24 months): visual acuity, refraction, contrast sensitivity (CS) under photopic and mesopic conditions, binocular defocus curve and evaluation of the perception of disturbing visual symptoms with a validated questionnaire. Mean binocular uncorrected distance (UDVA), distance-corrected intermediate (DCIVA), uncorrected near (UNVA) and distance-corrected near visual acuities (DCNVA) were -0.09 ± 0.07, 0.04 ± 0.05, 0.17 ± 0.12, and 0.15 ± 0.10 logMAR, respectively. In the binocular defocus curve, mean distance-corrected visual acuity was over 0.20 logMAR for defocus levels from +1.50 to -3.00 D. No significant correlations of photopic pupil diameter with postoperative visual data were found (-0.165 ≤ r ≤ 0.192, p ≥ 0.235). Moderate correlations of mesopic pupil size were found with visual acuities for the defocus levels of -2.50 (r = 0.454, p = 0.003), -3.00 (r = 0.609, p < 0.001), -3.50 (r = 0.519, p < 0.001), and -4.00 D (r = 0.403, p = 0.010). Only significant differences were found between mesopic and photopic CS for 12 cycles/degree (p = 0.010). No cases of severe glare or halos were detected. In contrast, 10% of patients referred the severe perception of starbursts postoperatively. Full spectacle independence was referred by almost all patients (90%). The IOL demonstrates effective visual restoration at various distances, characterized by high levels of visual quality and minimal dependence on pupil dynamics.

Optical and retinal changes influenced by different lighting conditions

Retinal morphology, specifically in its curvature, and ocular aberrations change when the eye adapts to different lighting conditions, including photopic, scotopic, mesopic, blue light, and red light. Sixty healthy young subjects with refractive error less than ±4.00D of sphere and 3.00D of cylinder, not suffering from accommodative problems, ocular or systemic pathology, and not having used electronic devices half an hour before or having taken substances that alter the retina during the 2 hours prior to the study were included. The subjects adapted to five lighting conditions, each for 5 minutes, in a controlled environment. Ocular aberrometry and Optical Coherence Tomography (OCT) were taken to capture images of the central and peripheral retina before (baseline measurement) and after adaptation to each lighting condition. The OCT images were exported and processed to analyze retinal curvature, obtaining parameters such as eccentricity, asphericity and shape factor. The results showed that the shape of the retina is hyperbolic prolate, becoming flatter in scotopic and blue light conditions, and more curved in mesopic conditions. Retinal curvature was closest to baseline under red light and photopic conditions. Aberrometric differences, particularly in the C(2,0) polynomial for defocus, showed higher values in mesopic, baseline, and scotopic conditions, and lower values in photopic, blue light, and red light. Significant differences were also observed in spherical aberrations C(4,0) and C(6,0), vertical coma C(3,-1), and trefoil C(3,-3). The spherical equivalent indicated more myopic values in mesopic, baseline, and scotopic conditions, and more hyperopic values in blue, photopic, and red light, suggesting a link between myopia and lower luminosity. The study concludes that illumination affects retinal curvature and ocular refraction, influencing myopia.

Reduced Monocular Accommodation Abilities with Laptop Usage Under Scotopic Ambient Illumination

Laptops are widely used even in dark scotopic rooms. This study compares monocular accommodation statuses with laptop usage under three illuminations. Thirty university students read on a laptop for 5 minutes under scotopic, mesopic, and photopic conditions. The monocular amplitude of accommodation, accommodation facility, and accommodation error are measured for each illumination. Repeated measure ANOVA shows a significant difference in the amplitude, facility, and error between different illuminations [F (1.49, 43.18) = 10.61, p&lt;0.001], [F (1.65, 36.30) = 6.78, p=0.005] and [F (2, 56) = 3.65, p=0.032]. Scotopic illumination reduces monocular accommodation abilities with laptop usage.

Prediction of visual outcomes using virtual implantation of a trifocal intraocular lens in presbyopic lens exchange patients.

To assess the reliability of a novel virtual IOL implantation device to predict the outcomes of a trifocal IOL. Clinical sites in Spain and Germany. Prospective multicenter study. Preoperative measurements obtained by the virtual implantation of AT LISA tri 839MP IOL (Carl Zeiss Meditec AG, Jena, Germany) with VirtIOL device (10Lens S.L.U., Terrassa, Spain) were compared to postoperative (month 3) outcomes following the IOL implantation. Evaluated metrics were defocus curve, contrast sensitivity (both in photopic conditions), and visual phenomena (visual angle size of burst and annular pattern) in mesopic conditions. The study included 45 presbyopic non-cataract patients (mean age 56.16±5.03 years). VirtIOL device reasonably predicted the shape of the defocus curve, especially in the intermediate vision range, but underestimated postoperative visual acuities mainly at the defocus range between +1.0D and -3.5D. The difference between predicted and achieved visual acuity was -0.11±0.13 logMAR (p<0.001) for 0.0D defocus and -0.16±0.15D logMAR (p<0.001) for -2.50D defocus. The shape of the contrast sensitivity curve was almost identical for predicted and achieved measurements, but the device underestimated the values by ≈0.3 logCS units for each spatial frequency. Visual phenomena were similar between the predicted and achieved outcome (predicted vs. achieved: burst pattern 2.65±0.97° vs. 2.74°±0.95°, p=0.63; annular pattern: 0.88±0.42° vs. 0.93±0.49°, p=0.59). The device reasonably predicted the pattern of measured variables. Visual acuity/contrast sensitivity reduction might be attributed to viewing the objects through a more complex optical system and would need to be accounted for in clinical studies.

Effects of three wavelength-cut lenses on visual function in the photopic and mesopic conditions

Effects of three wavelength-cut lenses on visual function in the photopic and mesopic conditions

Microperimetry Sensitivity Correlates to Structural Macular Changes in Adolescents with Achromatopsia Unlike Other Visual Function Tests.

Objectives: Achromatopsia (ACHM) is a rare autosomal, recessively inherited disease that is characterized by cone dysfunction, for which several gene therapies are currently on trial. The aim of this study was to find correlations between the morphological macular changes identified using optical coherence tomography (OCT) and some visual functional parameters. Visual acuity (VA), contrast sensitivity (CS), and macular sensitivity obtained by means of microperimetry were assessed. Methods: Adolescents with ACHM underwent macular microperimetry (S-MAIA device) in mesopic condition, macular OCT, best corrected visual acuity (BCVA), low luminance visual acuity (LLVA), near vision acuity (NVA), and CS measurement. Results: Eight patients (15 eyes) with ACHM were analyzed. The mean age was 17 ± 2.7 years, and genetic variants involved the CNGA3 gene (37.5%) and CNGB3 gene (62.5%). OCT staging significantly correlated with microperimetry sensitivity parameters, namely the sensitivity of the central foveal point (p = 0.0286) and of the first and second perifoveal rings (p = 0.0008 and p = 0.0014, respectively). No correlations were found between OCT staging and VA measurements, nor with CS value. Conclusions: Among the extensive evaluated visual function tests, only microperimetry sensitivity showed a correlation with morphological macular changes identified at OCT. Microperimetry sensitivity may thus represent a useful visual function tool in natural ACHM history studies considering the upcoming research on gene therapies for the treatment of ACHM.

Evaluation of Visual Outcomes in Patients With Aberrated Corneas Implanted With the IC-8 Small-Aperture IOL.

To assess the visual outcomes in patients with cataract implanted with a small-aperture intraocular lens (IOL) in eyes with aberrated corneas. This prospective, non-interventional, single-center clinical study was conducted at Singapore National Eye Centre, Singapore. Twenty-one patients with aberrated corneas had IC-8 IOL (Bausch & Lomb, Inc) implantation. An aberrated cornea was defined as from natural causes: keratoconus (n = 1, 4.8%), high coma (n = 2, 9.5%), corneal scar (n = 1, 4.8%), or iatrogenic causes: keratorefractive procedure (n = 17, 86%). Uncorrected and corrected visual acuities were measured at distance (600 cm) (UDVA and CDVA), intermediate (66.7 cm) (UIVA and CIVA), and near (40 cm) (UNVA and CIVA). Defocus curve was tested monocularly and binocularly. Contrast sensitivity (CS) was measured under photopic and mesopic conditions with and without glare. In IC-8 eyes, the mean ± standard deviation UDVA, UIVA, and UNVA was 0.24 ± 0.18, 0.19 ± 0.18, and 0.14 ± 0.14 logMAR, respectively. Mean CDVA, CIVA, and CNVA in IC-8 eyes was 0.12 ± 0.17, 0.16 ± 0.15, and 0.19 ± 0.13 logMAR, respectively. Binocular mean UDVA, UIVA, and UNVA was 0.07 ± 0.10, 0.07 ± 0.10, and 0.13 ± 0.12 logMAR, respectively. Defocus curve testing yielded a depth of focus of 1.50 D monocularly and 2.00 D binocularly at a 0.2 logMAR threshold. Photopic binocular CS with and without glare improved over monocular CS of IC-8 and fellow eyes under all spatial frequencies. Mesopic binocular CS with and without glare were similar among monocular IC-8 and fellow eyes across spatial frequencies. Most patients reported low levels of visual symptoms. The IC-8 IOL provides good monocular and binocular visual outcomes for patients with cataract who had aberrated corneas. [J Refract Surg. 2024;40(10):e716-e723.].

The effect of sunglass filters on contrast sensitivity, monocular eye closure, and blinking rate in people with intermittent exotropia

ABSTRACT Clinical relevance Transient monocular eye closure and photosensitivity under bright light have been reported in people with intermittent exotropia (IXT). The exact mechanism of these symptoms has not been established. Background This study examines the effect of sunglass filters on contrast sensitivity (CS), transient monocular eye closure, and blinking rate under bright light in people with IXT. Methods Forty participants with IXT and complaints of photosensitivity were included in the study. The binocular CS test was performed under mesopic and photopic conditions with and without glare, and with and without two filters with different grades of light transmission (filter 1: 44–80%; filter 2: 20–43% light transmittance). The effect of two filters on transient eye closure, contrast sensitivity, and blinking rate was assessed under bright light. Also, participants were divided into 3 groups based on their degree of control of fusion (good, fair, and poor control). Results The mean age of the participants was 12.0 years ± 8.0 (standard deviation) (range: 7–40 years). There was no significant difference between the age (p = 0.139), stereopsis (p = 0.134), as well as the near and far degree of deviation (p = 0.516, and p = 0.237) between the three groups of fusion control. Under mesopic conditions with glare, mean binocular CS was significantly higher with filters (p < 0.001). Without filters, 57.5% of the participants exhibited monocular eye closure under a photopic setting with additional glare. No participant showed eye closure using filter 2. People in the poor control group showed exodeviation before monocular eye closure (62.5% without filter and 12.5% with filter 1, p = 0.01). The blinking rate decreased from 36.0 ± 4.0 blinks per minute without filter to 21.0 ± 3.0 using filter 1, and 20.0 ± 3.0 with filter 2. Conclusion In people with IXT, wearing sunglass filters of different transmittance reduces monocular eye closure and blinking rate under bright light. To improve these symptoms, sunglasses can be considered for IXT.

Clinical Outcomes after Implantation of a Novel Binocular Complementary Extended Depth-of-Focus Intraocular Lens Compared to Bilateral Low Near-Add Multifocal Intraocular Lenses

Introduction: Nowadays, patients expect to be less spectacle dependent at all distances after cataract surgery. However, all intraocular lens (IOL) models that currently offer this function can also have negative visual effects. Aim of this study was therefore to compare the visual function performance of a novel and a conventional IOL solution for multifocality. Methods: Patients scheduled for bilateral cataract surgery were randomized to receive one of two different IOL combinations: either a binocular complementary extended depth-of-focus IOL set or a low near-add MIOL. Patients had visual acuity (VA) assessment at distance, intermediate, and near as well as evaluation of contrast sensitivity, halometry, and reading performance. Results: In total, 56 eyes of 28 patients were enrolled. At 6 months, there were no statistically significant differences in binocular VA between the ARTIS SYMBIOSE and the AT LARA. Contrast sensitivity, measured binocularly, at 1.5 cycles per degree under photopic conditions without glare was 1.54 logCS with the ARTIS SYMBIOSE and 1.43 logCS with the AT LARA (p = 0.046), under mesopic conditions with glare at 1.5 and 3 cycles per degree 1.31 logCS and 1.28 logCS with the ARTIS SYMBIOSE, respectively, compared to 0.58 logCS and 0.51 logCS with the AT LARA (p = 0.002; p = 0.006). Binocular halos and reading performance between both groups were similar. Conclusion: There were no significant differences between both groups in VA at different distances, reading ability, or halometry. The contrast sensitivity at low spatial frequencies was better in the ARTIS SYMBIOSE group under photopic conditions without glare as well as mesopic conditions with glare, which could potentially improve quality of vision with these IOLs, especially under mesopic conditions.

The Effect of Alternating Monocular Instillation of 0.125% Atropine in Korean Children with Progressive Myopia.

Objectives: To identify the effect of alternating monocular instillation (AMI) of 0.125% atropine in Korean children with progressive myopia. Methods: This retrospective single-center study included 120 children with progressive myopia. A total of 60 children (mean age 9.2 ± 2.0 years) wearing glasses who received AMI of 0.125% atropine for one year were allocated to the treatment group. The remaining 60 children (mean age 9.2 ± 1.9 years) with the same refraction, SE, and axial length (AL) who did not receive any treatments except for wearing glasses were allocated to the control group. Ocular findings and the progression rate were compared between the groups pre- and post-treatment, and adverse events were investigated in the treatment group. Results: The mean spherical equivalent (SE) at baseline was -3.87 ± 1.55 D in the control group and -3.90 ± 1.56 D in the treatment group. Pre-treatment SE, age, and AL were similar between the groups; however, post-treatment SE and AL changes were smaller in the treatment group (-0.36 ± 0.46 D/y, 0.21 ± 0.20 mm/year in the treatment group vs. -1.02 ± 0.57 D/y, 0.51 ± 0.20 mm/year in the control group) (Ps < 0.001). The pre-treatment progression rate diminished in the treatment group compared to the control group after one year (p < 0.001), and the changes in pupil size under mesopic and photopic conditions in the treatment group increased by 0.03 ± 0.05 mm and 0.76 ± 0.90 mm, respectively. Regarding adverse events, a tingling sensation was noted in two patients (3.3%) in the treatment group. Conclusions: Alternating monocular 0.125% atropine eye drop instillation may be effective and suitable for progressive myopia in Korean children.

CHARACTERIZATION OF VAULT WITH TWO MODELS OF POSTERIOR CHAMBER PHAKIC INTRAOCULAR LENSES.

To evaluate and compare the dynamic vault range (DVR) as well as the asymmetry of the vault during a 3-month follow-up after the implantation of two posterior chamber phakic intraocular lenses (pIOLs). Aver Clinic, Madrid, Spain. Prospective comparative study. One hundred and nineteen eyes (65 patients) that underwent refractive surgical correction with implantation of one of two distinct pIOLs were enrolled: Eyecryl Phakic from Biotech Vision Care (Eyecryl group, 72 eyes) and Evo Visian Implantable Contact Lens from Staar Surgical (ICL group, 47 eyes). Besides evaluation of visual acuity, refraction, and ocular integrity, the pIOL vault was measured centrally and at 2 mm nasally and temporally as well as the DVR from photopic (50 lux) to mesopic (10 lux) illuminations conditions. No significant differences were found between pIOL groups in visual and refractive outcomes (p≥0.454). No significant differences between groups were found in central (523.72±168.4 vs. 494.16±156.7 µm, p=0.248) and temporal vault (499.43±155.8 vs. 431.28±150.5 µm, p=0.067). However, nasal vault was significantly lower in ICL group (465.6±149.1 vs. 375.4±144.0 µm, p=0.045). A trend to a larger DVR was observed in the ICL group, although differences between groups did not reach statistical significance (54.00±36.39 vs. 86.5±57.9 µm p=0.070). The pIOL diameter only correlated significantly with vault measurements in ICL group (r≥0.650, p<0.001). The Eyecryl pIOL shows more symmetric vaults and a trend to fewer light-induced changes in the central vault compared to the ICL pIOL. The clinical relevance of this finding should be investigated further.

Retinal inputs that drive optomotor responses of mice under mesopic conditions

Optomotor responses are a popular way to assess sub-cortical visual responses in mice. We studied photoreceptor inputs into optomotor circuits using genetically-modified mice lacking the exocytotic calcium sensors synaptotagmin 1 (Syt1) and 7 (Syt7) in rods or cones. We also tested mice that in which cone transducin, GNAT2, had been eliminated. We studied spatial frequency sensitivity under mesopic conditions by varying the spatial frequency of a grating rotating at 12 deg/s and contrast sensitivity by varying luminance contrast of 0.2c/deg gratings. We found that eliminating Syt1 from rods reduced responses to a low spatial frequency grating (0.05c/deg) consistent with low resolution in this pathway. Conversely, eliminating the ability of cones to respond to light (by eliminating GNAT2) or transmit light responses (by selectively eliminating Syt1) showed weaker responses to a high spatial frequency grating (3c/deg). Eliminating Syt7 from the entire optomotor pathway in a global knockout had no significant effect on optomotor responses. We isolated the secondary rod pathway involving transmission of rod responses to cones via gap junctions by simultaneously eliminating Syt1 from rods and GNAT2 from cones. We found that the secondary rod pathway is sufficient to drive robust optomotor responses under mesopic conditions. Finally, eliminating Syt1 from both rods and cones almost completely abolished optomotor responses, but we detected weak responses to large, bright rotating gratings that are likely driven by input from intrinsically photosensitive retinal ganglion cells.

The Glowport - Illuminated vitrectomy trocar cannulas.

The use of small-gauge trocar cannulas during transconjunctival sutureless pars plana vitrectomy (PPV) facilitates the smooth transition of instruments into the posterior segment and reduces trauma. However, room lighting is routinely dimmed during PPV, thereby making cannula visualization difficult and hence compromising efficient instrument exchange. We report the use of a frugal, fluorescent "glow-in-the-dark" ring placed over vitrectomy cannulas to visualize the cannula entry, thereby providing a smooth and efficient instrument exchange. We 3D-printed phosphorescent rings of optimum inner diameter to comfortably fit around the trocar cannula (The Glowport). Two such rings are fitted into the two trocar cannulas prior to surgery initiation. The cannulas are then passed via sclerostomy as performed in routine PPV. The light from the fiberoptic endo-illuminator is focused over the rings for approximately 5 seconds to activate the photoluminescence. Under mesopic conditions, the fluorescence provides visualization of the cannula entry and helps in the facilitation of smooth entry and exchange of instruments into the globe for performing vitreoretinal surgical procedures, which helps in reducing ocular touch errors as well as surgical time. The Glowport is a frugal device retrofitted onto the trocar cannulas and helps in the smooth entry and exchange of instruments under darkroom conditions, which are required in vitreoretinal surgery.

Visual Function and Driving Performance Under Different Lighting Conditions in Older Drivers: Preliminary Results From an Observational Study.

Age-related vision changes significantly contribute to fatal crashes at night among older drivers. However, the effects of lighting conditions on age-related vision changes and associated driving performance remain unclear. This pilot study examined the associations between visual function and driving performance assessed by a high-fidelity driving simulator among drivers 60 and older across 3 lighting conditions: daytime (photopic), nighttime (mesopic), and nighttime with glare. Active drivers aged 60 years or older participated in visual function assessments and simulated driving on a high-fidelity driving simulator. Visual acuity (VA), contrast sensitivity function (CSF), and visual field map (VFM) were measured using quantitative VA, quantitative CSF, and quantitative VFM procedures under photopic and mesopic conditions. VA and CSF were also obtained in the presence of glare in the mesopic condition. Two summary metrics, the area under the log CSF (AULCSF) and volume under the surface of VFM (VUSVFM), quantified CSF and VFM. Driving performance measures (average speed, SD of speed [SDspeed], SD of lane position (SDLP), and reaction time) were assessed under daytime, nighttime, and nighttime with glare conditions. Pearson correlations determined the associations between visual function and driving performance across the 3 lighting conditions. Of the 20 drivers included, the average age was 70.3 years; 55% were male. Poor photopic VA was significantly correlated with greater SDspeed (r=0.26; P<.001) and greater SDLP (r=0.31; P<.001). Poor photopic AULCSF was correlated with greater SDLP (r=-0.22; P=.01). Poor mesopic VUSFVM was significantly correlated with slower average speed (r=-0.24; P=.007), larger SDspeed (r=-0.19; P=.04), greater SDLP (r=-0.22; P=.007), and longer reaction times (r=-0.22; P=.04) while driving at night. For functional vision in the mesopic condition with glare, poor VA was significantly correlated with longer reaction times (r=0.21; P=.046) while driving at night with glare; poor AULCSF was significantly correlated with slower speed (r=-0.32; P<.001), greater SDLP (r=-0.26; P=.001) and longer reaction times (r=-0.2; P=.04) while driving at night with glare. No other significant correlations were observed between visual function and driving performance under the same lighting conditions. Visual functions differentially affect driving performance in different lighting conditions among older drivers, with more substantial impacts on driving during nighttime, especially in glare. Additional research with larger sample sizes is needed to confirm these results.

Visual and Refractive Outcomes After Bi-aspheric Trifocal Toric Diffractive Intraocular Lens Implantation

Purpose: To assess clinical outcomes after cataract surgery with bilateral implantation of a new bi-aspheric diffractive intraocular lens (IOL). Methods: Thirty patients underwent bilateral implantation of the Asqelio Trifocal Toric IOL (AST Products, Inc) and were evaluated 3 months postoperatively. Main outcomes included refractive error, photopic monocular and binocular uncorrected and corrected distance (UDVA, CDVA), intermediate (UIVA, CDIVA) at 60 cm, and near (UNVA, CDNVA) at 40 cm visual acuities. Mesopic monocular and binocular CDNVA were also measured. Defocus curves, binocular contrast sensitivity under photopic and mesopic conditions with and without glare and rotational stability were determined. Patients completed Catquest-9SF and visual symptoms questionnaires. Results: Average values of binocular photopic CDVA, CDIVA, and CDNVA, and mesopic CDNVA were −0.04 ± 0.06, 0.02 ± 0.08, 0.02 ± 0.07, and 0.22 ± 0.11 logMAR, respectively. All patients achieved cumulative CDVA ⩾ 20/25, and CDIVA and CDNVA of 20/32 or better. Binocular depth of focus was approximately 3.25 diopters (D). Mean postoperative spherical equivalent was −0.08 ± 0.26 D, with 95% of eyes within ±0.50 D. Mean postoperative refractive cylinder was −0.22 ± 0.27 D, with 91.67% of eyes within 0.50 D or less, respectively. IOL rotation averaged 0.25 ± 0.65 degrees, all eyes having rotation of less than 5 degrees. Contrast sensitivity was within or above normal levels under photopic and mesopic conditions, with or without glare, except for 12 cpd under mesopic conditions with glare. Questionnaire responses indicated 96.67% of patients were satisfied or very satisfied with postoperative vision, and 80.00% to 96.67% reported no difficulty in different daily activities. Conclusions: The Asqelio Trifocal Toric IOL demonstrated favorable outcomes, providing excellent visual performance at all distances, precise refractive results, and remarkable rotational stability. Patients reported high satisfaction levels and minimal difficulty in daily activities. [ J Refract Surg . 2024;40(6):e407–e419.]

Femtosecond laser-assisted in situ keratomileusis versus small-incision lenticule extraction: current approach based on evidence.

Laser keratorefractive surgery achieves excellent visual outcomes for refractive error correction. With femtosecond laser, small incision lenticule extraction (SMILE) is an increasingly viable alternative to laser-assisted in situ keratomileusis (LASIK). Comparative studies demonstrate similar efficacy and predictability between SMILE and LASIK, making it difficult for clinicians to choose which to use. This review thus compares femtosecond-LASIK (FS-LASK) and SMILE in various scenarios, to assist clinicians in deciding which refractive surgery procedure to recommend. SMILE may be superior for highly myopic eyes due to a smaller decrease in functional optical zone. SMILE further induces less spherical aberration and less overall higher order aberrations in mesopic conditions. SMIILE also has less postoperative dry eye, making it suitable those with preexisting dry eye. For low to moderate myopic astigmatism correction, FS-LASIK has less undercorrection compared to SMILE. Lastly, SMILE has not yet received Food and Drug Administration or Conformité Européenne approval for hyperopic correction, rendering FS-LASIK the choice of procedure for hyperopic correction. Both FS-LASIK and SMILE demonstrate good efficacy and predictability. Understanding specific clinical scenarios where one may be superior to the other will aid clinicians in choosing the most suitable procedure for personalized care.

Efficacy of a new refractive multifocal contact lens for presbyopia

This prospective single-arm study aimed to evaluate the clinical efficacy and safety of a refractive multifocal contact lens for the correction of presbyopia in 22 patients. The participants underwent clinical examinations before and 1 week after wearing a refractive multifocal contact lens (OptaCon ZOOM). The primary endpoints were the corrected distance visual acuity (CDVA) and distance-corrected near visual acuity (DCNVA). Defocus curve, contrast sensitivity, and ocular surface disease index (OSDI) were analyzed. A slit-lamp examination was performed for safety analysis. Contact lens comfort and patient satisfaction were assessed using a questionnaire. No significant difference in CDVA was observed before and 1 week after refractive multifocal contact lens use (p = 0.127), whereas DCNVA was significantly improved after 1 week (p < 0.001). The contrast sensitivity was not significantly affected at any spatial frequency under mesopic or photopic conditions. OSDI was significantly increased (p = 0.023). The patient-reported satisfaction scores were 96.2, 91.9, and 85.0 out of 100 at far, intermediate, and near distances, respectively. No significant adverse events were observed. Refractive multifocal contact lenses improved near vision while maintaining distance vision in presbyopic patients, without compromising contrast sensitivity. The study results suggest that OptaCon ZOOM can be considered safe and effective for the correction of presbyopia.

In-Depth Retinal Sensitivity Assessment With the MP3 Type S Microperimeter: A Methods Study.

Retinal sensitivity is frequently listed as an end point in clinical trials, often with long working practices. The purpose of this methods study was to provide a new workflow and reduced test time for in-depth characterization of retinal sensitivity. A workflow for the MP3-S microperimeter with detailed functional characterization of the retina under photopic, mesopic, and scotopic conditions was evaluated. Grids of 32 and 28 test positions for photopic/mesopic and scotopic, respectively, were tested in 12 healthy individuals and compared with an established 68-point grid for test time, mean sensitivity (MS), and bivariate contour ellipse area (BCEA). The mean test time (range; ±SD) was 10.5 minutes (8.4-14.9; ±2.0) in the 68-point grid and 4.3 minutes (3.8-5.0; ±0.4) in the 32-point grid, which was significantly different (P < 0.0001). The mean of difference in test time (±SD; 95% confidence interval) was 6.1 minutes (±2.0; 4.6-7.6). MS and BCEA were significantly correlated between grids (r = 0.89 and 0.74; P = 0.0005 and 0.014, respectively). Mean test time of subjects who underwent the full protocol (n = 4) was 2.15 hours. The protocol suggested herein appears highly feasible with in-depth characterization of retinal function under different testing conditions and in a short test time. The protocol described herein allows for characterization of the retina under different testing conditions and in a short test time, which is relevant due to its potential for patient prognostication and follow-up in clinical settings and also given its increasing role as a clinical trial end point.