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The aim of this study was to collect the scientific literature on the correction of presbyopia with laser in situ keratomileusis (presbyLASIK) in last years and to analyse the quality of such scientific evidence using a validated methodology for conducting a systematic review. A total of 42 articles were initially identified, but after applying the selection criteria and an additional manual search a total of 23 articles were finally included: 2 non-randomized controlled clinical trials (NRCT) and 21 case series. Quality assessment of NRCTs and case series was performed with the ROBINS-I and the 20-criterion quality appraisal checklist defined by Moga et al. (IHE Publ 2012), respectively. For NRCT, the risk of bias was moderate in one study and serious in the other NRCT, being the main sources of risk, the domains related to confounding, selection of participants and measurement of outcomes. For case series studies, the main source of risk of bias was subjects not entering the study at the same point of the conditions (different levels of presbyopia). Likewise, a significant level of uncertainty was detected for the following items: consecutive recruitment of patients, blinding of outcome assessors to the intervention that the patient received, and conclusions of the study not supported by the results. Research on presbyLASIK to this date is mainly focused on case series generating a limited level of scientific evidence. The two NRCTs identified only demonstrated the potential benefit of combining the multiaspheric profile with some level of monovision in the non-dominant eye. The author DPP has been supported by the Ministry of Economy, Industry and Competitiveness of Spain within the program Ramón y Cajal, RYC-2016-20471.

PURPOSE: To conduct a critical review of the peer-reviewed literature on the use of supplemental multifocal intraocular lenses in the ciliary sulcus. METHODS: This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement recommendations. According to the inclusion and exclusion criteria defined, 15 articles were selected for the current systematic review. Each of them was analyzed carefully and their risk of bias was assessed with the Quality Assessment Tool for Case Series Studies from the National Heart, Lung, and Blood Institute. RESULTS: Data of 384 eyes from 227 patients were analyzed. Most of the studies reviewed had a short follow-up and poor or limited design, including case reports, case series, and clinical trials with several gaps in their methodology. Post-operative uncorrected distance and near visual acuity ranged from 20/40 to 20/20 and from 0.4 to 0.02 logMAR, respectively. Pigment dispersion (12 eyes) and deposits (13 eyes) were the most described complication. Dysphotopsia, glare, and halos were the more frequently reported visual disturbances. However, most of the patients reported a high level of satisfaction with their surgery. Most articles reviewed (13 of 15) achieved a risk of bias score between 6 and 8, representing a high level of evidence despite the study design limitations. CONCLUSIONS: Supplemental multifocal intraocular lenses seem to offer good distance and near visual results, leading to high levels of spectacle independence and patients' satisfaction, with limited complications associated. However, more studies with a more robust design are needed to confirm these trends. [ J Refract Surg . 2021;37(12):830–835.]

Strabismus is not a condition in itself but the consequence of an underlying problem. Eye misalignment can be caused by disease, injury, and/or abnormalities in any of the structures and processes involved in visual perception and oculomotor control, from the extraocular muscles and their innervations to the oculomotor and visual processing areas in the brain. A small percentage of all strabismus cases are the consequence of well-described genetic syndromes, acquired insult, or disease affecting the extraocular muscles (EOMs) or their innervations. We will refer to them as strabismus of peripheral origin since their etiology lies in the peripheral nervous system. However, in most strabismus cases, that is comitant, non-restrictive, non-paralytic strabismus, the EOMs and their innervations function properly. These cases are not related to specific syndromes and their precise causes remain poorly understood. They are generally believed to be caused by deficits in the central neural pathways involved in visual perception and oculomotor control. Therefore, we will refer to them as central strabismus. The goal of this narrative review is to discuss the possible causes behind this particular type of eye misalignment and to raise awareness among eyecare professionals about the important role the central nervous system plays in strabismus etiology, and the subsequent implications regarding its treatment. A non-systematic search was conducted using PubMed, Medline, Cochrane, and Google Scholar databases with the keywords “origins,” “causes,” and “etiology” combined with “strabismus.” A snowball approach was also used to find relevant references. In the following article, we will first describe EOM integrity in central strabismus; next, we will address numerous reasons that support the idea of central nervous system (CNS) involvement in the origin of the deviation, followed by listing several possible central causes of the ocular misalignment. Finally, we will discuss the implications CNS etiology has on strabismus treatment. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.

Purpose: To evaluate the prediction error (PE) after applying the Abulafia–Koch formula in an online calculator with and without consideration of anterior corneal surgically induced astigmatism (SIACornea). Methods: SIACornea models were calculated with a historical database of 204 right eyes (REs) from a single surgeon, either for manual (2.2 mm) or femtosecond (2.5 mm) temporal clear corneal incisions. PE was assessed in 58 REs operated by the same surgeon with a monofocal toric IOL and calculated, considering the PCA estimation in an online calculator with the combination of each one of the following SIACornea calculation approaches: (A) considering only significant centroids after stratification, (B) all centroids after stratification and (C) a single centroid without stratification. Results: The consideration of all centroids resulted in an underestimation of SIACornea in cases of preoperative against-the-rule astigmatism (ATR-A) and an overestimation in with-the-rule astigmatism (WTR-A). After stratification, SIACornea was only significant in preoperative ATR and oblique astigmatism cases for femtosecond incisions. PE considering PCA only was 0.03@160º. The combination with SIACornea resulted in a WTR-A surprise in preoperative ATR-A and WTR-A, however only being significant for preoperative ATR-A in calculation approaches B (0.29@84º) and C (0.21@80º). SIACornea addition to PCA estimation only reduced the centroid for oblique preoperative astigmatism. Conclusions: Surgeons should consider the calculation of the SIACornea after stratification by astigmatism type when using the same incision location (i.e. temporal). However, SIACornea derived from the anterior corneal surface should not be combined with PCA estimation for IOL power calculations.

Introduction: Positive dysphotopsia (PD) is a topic of great interest in intraocular lens (IOL) field. Several approaches have been developed from the physics, psychophysics and psychometry fields to measure PD. However, the complexity of characterizing this phenomenon and the lack of standardization have resulted in a considerable bias between studies that avoid its inclusion in systematic reviews and meta-analysis. Areas Covered: The purposes of this review were first to suggest a definition and classification of PD that minimize the bias between studies that use different questions to rate PD prevalence. Second, to describe the limitations found in psychophysical studies. Finally, to identify the associations between photic phenomena (PP) and the design of monofocal and multifocal IOLs. A non-systematic literature review was conducted from the last 30 years. Expert Opinion: PD can be defined as any bothering bright artifact perceived by patients along or around direct bright lights or reflected over objects located in the visual field. If the patient is not bothered by the artifact, the term PP should be used instead. Psychophysical approaches measure PP and not PD. Whereas LED approaches are preferable, these really measure Light Disturbance because the classification of PP cannot be differentiated.

To assess, following the standards, the results of safety, efficacy and predictability for a trifocal intraocular lens and to evaluate contrast sensitivity and visual acuity defocus curve.Fifty subjects operated on cataract surgery or refractive lens exchange with a trifocal intraocular lens have been recruited for the study. The monocular uncorrected visual acuity (VA) at far, intermediate (67 cm) and near (40 cm) distances in addition to corrected VA at far and near distances was evaluated at 1 week, 1 month and 3 months after surgery. Postoperative refraction, binocular contrast sensitivity function (CSF) and binocular defocus curves were also collected at the 3-month follow-up visit.Mean uncorrected VA was 0.10, 0.07 and 0.05 logMAR at far, intermediate and near distances. Corrected distance VA at far and near distances was 0.04 and 0.02 logMAR. Ninety percent and 100% achieved a spherical equivalent in ±0.50 D and ±1.00 D, respectively. CSF was above normal range for 12 and 18 cycles per degree (cpd) in all the conditions, inside the normal range in 1.5, 3 and 6 cpd and only decreased below normal range for 1.5 and 3 cpd in mesopic vision without glare.The procedure achieved a safety, efficacy and predictability similar to those reported by previous studies. The CSF was generally enhanced after the procedure in comparison to those reported in non-operated subjects above 60 years old. Previous studies might underestimate the effective distance of the intermediate and near foci.

Purpose: To identify the most sensitive visual performance metric for evaluating the pupil-dependency of a multifocal intraocular lens (MIOL) and to determine the pupil measurement method most correlated with such metric. Methods: Twenty-seven right eyes implanted with a MIOL were included in the analysis. Three pupil size measurements were obtained preoperatively and at 1 month after surgery with the Keratograph 5M system: photopic (PP), mesopic (MP), and the average from both (AP). Pupil was also measured with a rule (RP) under the same light conditions of postoperative visual performance measurements that included, corrected visual acuities (VA) at three distances (far, 67 cm and 40 cm), visual acuity (VADC) and contrast sensitivity defocus curves for optotype sizes of 0.3 logMAR (CSDC3) and 0.7 logMAR (CSDC7). Differences in visual performance were also analyzed for eyes with RP > 3 mm (Group A) and RP ⩽ 3 mm (Group B). Results: PP diameter decreased after surgery by 16% ( p = 0.001), whereas MP ( p = 0.013) and AP ( p = 0.008) decreased by 10%. The best agreement with RP was obtained for AP. Group B showed a trend to better performance than Group A for all the included metrics ( p > 0.05). From the three types of defocus curves, CSDC3 obtained generally highest statistical power for testing differences between groups. The strongest statistically significant correlations between pupil size and CSDC3 were obtained for RP and AP. Conclusion: The CSDC3 was the most sensitive metric to detect MIOL pupil-dependency. PR and AP were more correlated with CSDC3 than PP and MP.

Purpose To comprehensively evaluate visual function in eyes with geographic atrophy (GA) as compared to normal eyes. Patients and Methods Sixty-three eyes from 63 patients ≥50 years old were recruited for this observational study; 31 were identified as normal macular health eyes and 32 with GA. Visual function was tested with best corrected visual acuity (BCVA), low luminance visual acuity (LLVA), low luminance deficit (LLD), reading speed, macular integrity microperimetry, fixation stability, and contrast sensitivity function (CSF). Anatomic function was evaluated with spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF). Quality of life and vision were assessed with the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). Results Visual function and quality of life are reduced in patients with GA. Moderate and strong correlations in the GA group were found between maximum reading speed (r = 0.787) (p˂0.01), CS spatial frequency 3 cpd (r = 0.441) (p˂0.05), CS spatial frequency 6 cpd (r = 0.524) (p˂0.01), fixation P1 (r = 0.379) (p˂0.05), macular sensitivity (r = 0.484) (p˂0.05) and atrophic area (r = -0.689) (p˂0.01), and the VFQ-25 composite score. Conclusion The decreased visual function is reflected in a poor quality of life in patients with GA. Reading speed, contrast sensitivity, fixation, and macular sensitivity are strongly associated with vision-related quality of life. The results suggest the importance of the reading letter size in patients with GA. Microperimetry and reading speed are useful tools to better assess visual impairment in patients with GA.

PURPOSE: To assess the influence of reliability (repeatability and reproducibility) of eye parameter measurements on the prediction refraction by using the outcomes of nine optical biometers reported in the literature. METHODS: A search was conducted in PubMed focused on the outcomes from original studies regarding reliability. The mean population of within-subject standard deviation (Sw) was estimated from the mean samples reported in the included studies. Repeatability coefficients ( R ) for the mean population were computed as 2.77 × Sw. The influence of reliability on the prediction refraction for eye biometric parameters, such as mean corneal power in diopters (D) (Km), anterior chamber depth (ACD), and axial length (AXL), were evaluated using a thick lens formula. The lens thickness (LT), central corneal thickness (CCT), and white-to-white (WTW) distance were also evaluated. RESULTS: The repeatability of optical biometers ranged from 0.19 to 0.42 D for Km, from 0.04 to 0.13 mm for ACD, from 0.03 to 0.22 mm for AXL, from 0.06 to 0.13 mm for LT, from 5.5 to 17.7 µm for CCT, and from 0.18 to 0.48 mm for WTW distance. Total prediction refraction due to repeatability ranged from 0.21 to 0.61 D, with Km the variable that caused the major part of total prediction refraction variability, followed by AXL and ACD. Reproducibility for the evaluated variables was generally inside the repeatability ranges. CONCLUSIONS: New optical biometers are equally reliable as earlier technologies. Special attention should be focused on Km and AXL, which explain the major part of prediction refraction variability. [ J Refract Surg . 2022;38(2):120–127.]

Purpose To assess the influence in paired design studies of formulae comparison for intraocular lens (IOL) power calculation of using a single formula for deciding the implanted power with monofocal (mIOL) and multifocal (MIOL) lenses. Design Retrospective observational. Methods Ninety-six right eyes were retrospectively analyzed. Eyes were assigned in two independent groups, SG and HG, depending on the formula used for deciding the implanted power, SRK-T (n = 54) and Haigis (n = 42), respectively. Median absolute prediction error (MedAE) was evaluated between independent samples (SRK-T in SG vs Haigis in HG) and between paired samples (SRK-T vs Haigis in both SG and HG). Percentages of eyes within a specific range of prediction error (PE) were also calculated for both, the standard steps and the clinically relevant steps. Results MedAE difference was lower than 0.09 D between both formulas for the comparison of independent samples in the mIOL (p = 0.62) and MIOL (p = 0.83) groups. However, paired samples resulted in better MedAE for SRK-T in the SG (0.14 D lower, p = 0.003) and for Haigis in the HG (0.07 D lower, p = 0.015), but only in the mIOL group. These small differences were also manifested, but not reaching statistical significance (p > 0.05), in the percentage of eyes achieving a specific range of PE, especially in the mIOL group. Conclusions A small superiority for the formula used for selecting the final implanted IOL power can appear in studies following current standards. These studies should clearly specify which formula was used for selecting the implanted power.

To evaluate the prediction error (PE) obtained in Phacoemulsification (Phaco) or Femtosecond (Femto) surgeries without considering posterior corneal astigmatism correction (non-PCA) versus the correction based on Abulafia-Koch + Medicontur (AK) and Barrett calculators in toric intraocular lens (IOL) power calculation. 58 right eyes were retrospectively retrieved from our database. Two groups formed by 28 and 30 eyes depending on the surgery type, Phaco or Femto respectively, were defined. Astigmatism PE were evaluated considering the approach used for calculation of the implanted IOL power (AK) versus the estimation of PEs in non-PCA and Barrett formula. A doubly-multivariate analysis was conducted to assess the differences between-surgery types, within-methods of calculation, and interaction. Mean centroid PE was significantly different between non-PCA, AK and Barrett approaches (p &lt, 0.0005), and neither differences (p &lt, 0.239) nor interaction (p = 0.672) between Phaco or Femto were found. Post-hoc univariate analysis showed a higher PE for the x-component of the non-PCA method versus AK (0.15 D, p &lt, 0.0005) and non-PCA versus Barrett (0.18 D, p &lt, 0.0005), though no differences were found between AK and Barrett (0.03 D, p = 0.93). Against-the-rule under-correction and with-the-rule overcorrection were found in both arms when PCA was not considered. Both calculators provide comparable clinical results.

Purpose To assess the degree of posterior capsular opacification (PCO) and its influence on contrast sensitivity defocus curve (CSDC) after implantation of two trifocal intraocular lenses (IOLs), Alsafit (AT) and Liberty (L), during a 12-month follow-up. A secondary aim was to evaluate the Nd:YAG capsulotomy rate in a long time. Methods Data from 63 subjects, 34 implanted with AT and 29 with L, were retrospectively analyzed for this pilot study. In those eyes without capsulotomy during the first year (n = 58), CSDC at 3 and 12 months after surgery and PCO grading were measured, with additional answering of a visual function questionnaire (VF-14) and a question of general satisfaction. The period after surgery up to capsulotomy or last on-demand visit without Nd:YAG was recorded for survival analysis beyond the 12-month follow-up. Results Total area under CSDC (TAUC) between 3 and 12 months decreased from 2.96 to 1.71 for AT (p 0.05) for L. Of eyes, 51.6, 19.3, and 29% with AT were graded as level 0, 1, and 2 of PCO, while 85.1, 11.1, and 3.7% of eyes with L were graded as level 0, 1, and 2 (p

(1) Background: To evaluate the efficacy at 6 years postoperative after the implantation of a trifocal intraocular lens (IOL) AT Lisa Tri 839MP. The secondary objective was to evaluate the contrast sensitivity defocus curve (CSDC), light distortion analysis (LDA), and patient reported outcomes (PROs). (2) Methods: Sixty-two subjects participated in phone call interviews to collect data regarding a visual function questionnaire (VF-14), a patient reported spectacle independence questionnaire (PRSIQ), and questions related to satisfaction and decision to be implanted with the same IOL. Thirty-seven of these subjects were consecutively invited to a study visit for measurement of their visual acuity (VA), CSDC, and LDA. (3) Results: The mean monocular distance corrected VA was −0.05, 0.08, and 0.05 logMAR at far and distances of 67 cm and 40 cm, respectively. These VAs were significantly superior to those reported in previous literature (p &lt, 0.05). The total area under the CSDC was 2.29 logCS/m−1 and the light distortion index 18.82%. The mean VF-14 score was 94.73, with 19.4% of subjects requiring spectacles occasionally for near distances, and 88.9% considering the decision of being operated again, (4) Conclusions: Long-term AT LISA Tri 839MP IOL efficacy results were equal or better than those reported 12 months postoperatively in previous studies. The spectacle independence and satisfaction rates were comparable to those reported in short-term studies.

The increase of the depth of focus (DOF) for the treatment of presbyopia or cataracts is a topic of great interest for anterior segment surgeons that have seen how new surgical possibilities to achieve DOF enlargement have emerged. Nowadays, several technologies to extend the DOF are available, from corneal laser refractive surgery (LRS) procedures in presbyopia to intraocular lens (IOL) implantation in cataract or refractive lens exchange. Some of these procedures are based on aspherical profiles, either in the cornea or in the IOL, which modulate the spherical aberration (SA) and therefore extend the light energy on different focal planes. The aim of this narrative review was to give an overall picture about the reasons why there is not a general solution persistent along time of SA induction to extend DOF, especially considering that SA depends on pupil diameter and this decreases with age.

Purpose: To evaluate the incidence of central islands after 6-month follow-up of Small Incision Lenticule Extraction (SMILE) and to assess their role in safety and accuracy. Methods: Analysis of the preoperative and postoperative corneal tomography, best spectacle refraction and corrected distance visual acuity of 82 subjects that underwent SMILE. Incidence of central islands was assessed through total corneal spherical aberration (SA) over 4 mm of central diameter and the SA was compared between two groups with and without safety loss (CDVA difference ≥0.1 logMAR from preoperative). The cut-off value for detecting the risk of postoperative central island development was calculated. The influence in accuracy was calculated through magnitude of error of the spherical equivalent and astigmatism, both for spectacle refraction at corneal plane (SE-Rx and AST-Rx) and for total corneal refractive power at 3 mm (SE-TCRP3 and AST-TCRP3). Results: Five from 82 eyes resulted in a loss of safety, obtaining significant differences in SA, both preoperatively (p = .01) and postoperatively (p = .007) after stratification by safety loss. A preoperatively cut-off value ≤0.012 μm of SA predicted the appearance of central islands with sensitivity of 100% and specificity of 75%. Despite postoperative SA being related to the preoperative spherical equivalent, for both SE-Rx and SE-TCRP3, this tendency disappeared after readjusting results according to a nomogram. Conclusions: Central islands in SMILE, despite being a rare adverse event, can affect the safety of the procedure and are related to preoperative central steepness, not corrected by the spherical lenticule, which is clearly visible postoperatively.

PURPOSE: To evaluate the distribution of pupil size in patients implanted with multifocal intraocular lenses (IOLs) and to assess the variations according to age. METHODS: A total of 168 eyes that had implantation of several multifocal IOLs and were measured at the 3-month follow-up visit were included in the analysis. The Keratograph 5M (Oculus Optikgeräte) was used to measure the photopic and mesopic pupil size, as well as the average between both (average pupil size). Eyes were stratified in four groups by age: 50 years or younger, 51 to 60 years, 61 to 70 years, and older than 70 years. RESULTS: Considering the total sample, 84.5% and 95.8% of eyes had a photopic pupil size of 3 and 3.5 mm or less, respectively. The mesopic pupil size was greater than 4.5 mm in 39.3% and greater than 5 mm in 16.7% of eyes. The average pupil size was 3.5 and 4 mm or less in 54.2% and 85.1% of eyes, respectively. Mesopic pupil size resulted in a steeper decrease with age than photopic pupil size: 0.028 versus 0.015 mm/year, respectively. Statistically significant differences were found among the four age groups ( P < .0005). No significant mean differences were found between multifocal IOL models for photopic pupil size, mesopic pupil size, or average pupil size ( P > .05). CONCLUSIONS: Eyes implanted with multifocal IOLs had a photopic pupil size of 3.5 mm or less and mesopic pupil size of 5 mm or less. Mesopic and photopic pupil size decreased 0.28 and 0.15 mm per decade, respectively. This information can help surgeons to understand the general functioning of multifocal IOLs whose performance varies with pupil size. [ J Refract Surg . 2020;36(11):750–756.]

Purpose To evaluate the agreement between subjective high and low contrast visual acuity (VA) and predicted values from double-pass system measurements in healthy candidates to laser refractive surgery. Methods Ninety-two eyes measured during the preoperative screening to laser refractive surgery were included in this retrospective analysis. High contrast subjective visual acuity (HCVA) and low contrasts at 20% (LCVA20) and 9% (LCVA9) were compared with the predicted VA obtained with a commercial double-pass system (OQAS) at the same levels of contrast, 100% (OV100), 20% (OV20), and 9% (OV9). The agreement was evaluated with Bland-Altman analysis computing the limits of agreement (LoAs) and the correlations with the spearman rho. Results An underestimation of VA was obtained with the double-pass system for the highest contrast. Differences between predictive and subjective measurements were statistically significant for 100% contrast (− 0.08 logMAR, p

[EN] Purpose: To assess the peripheral refraction induced by Fractal Contact Lenses (FCLs) in myopic eyes by means of a two-dimensional Relative Peripheral Refractive Error (RPRE) map. Materials and Methods: This study involved 26 myopic subjects ranging from -0.50 D to -7.00 D. FCLs prototypes were custom-manufactured and characterized. Corneal topographies were taken in order to assess correlations between corneal asphericity and lens decentration. Two-dimensional RPREs were measured with an open-field autorefractor at 67 points, covering the central 60 x 30 degrees of the visual field. The bidimensional RPRE vector components: M, J(0) and J(45) of the difference between the values obtained with and without the FCLs in the eye were obtained. Additionally, the FCL-induced peripheral refraction in tangential and sagittal planes was computed along the horizontal meridian. Results: Induced by the FCLs, significant differences for all vector components were found in the peripheral retina. FCLs were decentered a mean of 0.7 +/- 0.19 mm to the temporal cornea. The two-dimensional RPRE maps manifested the FCLs decentration. In particular, M varied asymmetrically between nasal and temporal retina after fitting the FCLs with a significant increment of the myopic shift beyond 10o (p < 0.05). No correlations were found between the amount of lens decentration and the asphericity of the cornea along temporal and nasal sides. However, significant correlations were found between the corneal asphericity and vector components of the RPRE in naked eyes. FCLs produced an increasing myopic shift in tangential and sagittal power errors along the horizontal meridian. Conclusions: As predicted by ray-tracing simulations, FCLs fitted in myopic eyes produce a myopic shift of the RPRE. The two-dimensional RPRE maps show information about the lens performance that is hidden in the conventional one-dimensional meridional representations., This work was founded by Ministerio de Economía y Competitividad FEDER (Grant DPI2015-71256-R), and by Generalitat Valenciana (Grant PROMETEOII-2014-072), Spain.

The hypothesis that small-incision lenticule extraction provides better preservation of corneal biomechanics than previous laser refractive techniques has led to a growth in the interest in clinical and experimental research in this field. This hypothesis is based on the fact that corneal layers with greater stiffness are preserved with this new technique. However, this hypothesis is controversial because clinical research has shown a great disparity in the outcomes. In this review, we performed an in-depth analysis of the factors that might affect corneal biomechanics in laser refractive surgery procedures from a macrostructural to a microstructural viewpoint. New advances in algorithms with current devices or the introduction of new devices might help unmask the possible advantages of small-incision lenticule extraction in corneal biomechanics.

Letter to the Editor

Purpose To comprehensively evaluate visual function in eyes with geographic atrophy (GA) as compared to normal eyes. Patients and Methods Sixty-three eyes from 63 patients ≥50 years old were recruited for this observational study; 31 were identified as normal macular health eyes and 32 with GA. Visual function was tested with best corrected visual acuity (BCVA), low luminance visual acuity (LLVA), low luminance deficit (LLD), reading speed, macular integrity microperimetry, fixation stability, and contrast sensitivity function (CSF). Anatomic function was evaluated with spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF). Quality of life and vision were assessed with the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). Results Visual function and quality of life are reduced in patients with GA. Moderate and strong correlations in the GA group were found between maximum reading speed (r = 0.787) (p˂0.01), CS spatial frequency 3 cpd (r = 0.441) (p˂0.05), CS spatial frequency 6 cpd (r = 0.524) (p˂0.01), fixation P1 (r = 0.379) (p˂0.05), macular sensitivity (r = 0.484) (p˂0.05) and atrophic area (r = −0.689) (p˂0.01), and the VFQ-25 composite score. Conclusion The decreased visual function is reflected in a poor quality of life in patients with GA. Reading speed, contrast sensitivity, fixation, and macular sensitivity are strongly associated with vision-related quality of life. The results suggest the importance of the reading letter size in patients with GA. Microperimetry and reading speed are useful tools to better assess visual impairment in patients with GA.

Purpose: To assess the impact of ocular biometric variables on the visual performance achieved with a low addition trifocal intraocular lens (MIOL). Methods: Retrospective observational study including 34 eyes. Preoperative measured variables included mean corneal power (Km), corneal regular astigmatism (RA), anterior chamber depth (ACD), axial length (AXL), total irregular astigmatism (IA), spherical aberration (SA) and distance from pupil center to vertex normal (µ). Same variables were retrieved from the three month visit follow-up in addition to the actual lens position (ALP), the calculated effective addition (EA), the IOL centration from vertex normal (d), and the visual acuity defocus curve. The area under the defocus curve was computed along the total curve (TAUC) and ranges for far (FAUC), intermediate (IAUC) and near vision (NAUC). The sample was split in two groups of 17 eyes with TAUCs above and below the mean, and the differences among groups for different ocular parameters were assessed. Results: The group of eyes above TAUC of 2.03 logMAR*m-1 showed significantly lower Km and greater AXL and SA. Km was negatively correlated with TAUC and NAUC. NAUC was negatively correlated with IA and positively with d. A multiple lineal regression model including Km, d, and IA predicted NAUC (r-square = 34%). No significant differences between IA and SA were found between preoperative and postoperative values but µ significantly decreased after surgery. Conclusions: The mean corneal power, irregular astigmatism, and centration from vertex normal should be considered for optimizing the near visual performance with this MIOL. Objetivo: Valorar el impacto de las variables biométricas oculares sobre el rendimiento visual con una lente intraocular trifocal de baja adición (MIOL). Métodos: Estudio observacional retrospectivo que incluyó 34 ojos. Las variables preoperatorias medidas incluyeron potencia corneal media (Km), astigmatismo regular corneal (AR), profundidad de la cámara anterior (ACD), longitud axial (AXL), astigmatismo irregular total (AI), aberración esférica (AE) y distancia entre el centro de la pupila y el vértice normal (µ). Algunas variables se obtuvieron de la visita de seguimiento a los tres meses, a las que se añadieron la posición real de la lente (ALP), la adición efectiva (AE), el centrado de las LIO desde el vértice normal (d), y la curva de desenfoque de agudeza visual. El área bajo la curva de desenfoque se calculó a lo largo de la curva total (TAUC) así como los rangos para visión de lejos (FAUC), intermedia (IAUC) y de cerca (NAUC). La muestra se dividió en dos grupos de 17 ojos con TAUCs por encima y por debajo de la media, valorándose las diferencias entre los grupos para los diferentes parámetros oculares. Resultados: El grupo de ojos con un valor por encima de TAUC igual a 2,03 logMAR*m-1 reflejó un menor Km y valores mayores de AXL y AE. Km se correlacionó negativamente con TAUC y NAUC. NAUC se correlacionó negativamente con AI, y positivamente con d. Un modelo de regresión lineal múltiple incluyendo Km, d, y AI realizó la predicción de NAUC (R2 = 34%). No se encontraron diferencias significativas entre AI y AE entre los valores preoperatorios y postoperatorios, aunque µ disminuyó significativamente tras la cirugía. Conclusiones: La potencia corneal media, el astigmatismo irregular y el centrado desde el vértice normal deberían considerarse para optimizar el desempeño visual de cerca con MIOL.

Purpose: To develop a new method that makes it easy to detect accuracy deficiencies of any intraocular lens power calculation formulae and to test it on 9 different formulae. Setting: IOA, Madrid, Spain Design: Retrospective observational case series. Methods: This study’s first stage included 3519 eyes from 3519 candidates to cataract surgery for which frequency distributions for the following biometric eye parameters were computed: axial length (AXL), anterior-chamber depth (ACD), lens thickness (LT), white-to-white (WTW) and mean corneal radius (Rm). The resulting data for each parameter were 5th, 25th, 75th and 95th percentile, which allowed us to define the corresponding normality range. In a second stage, the new graphic-representation method was tested for 9 different formulae in a sample of 70 eyes undergoing cataract surgery with multifocal intraocular lens (MIOL) implantation. Results: Normality ranges (defined as the 25th-to-75th-percentile interval) were 22.84 to 24.42 mm for AXL, 2.86 to 3.39 mm for ACD, 4.36 to 4.88 mm for LT, 11.64 to 12.19 mm for WTW and 7.52 to 7.87 mm for Rm, with lower sizes in women. No significant differences were found along the 9 formulae for percentage of eyes in ±0.50D (p=0.82) or ±1.00D (p=0.97). The new graphical method showed less accuracy in ±0.50 D for ACDs from 2.46 to 2.85 mm (5th to 25th percentile) for several formulae (p

Purpose: To assess differences in a new objective metric obtained with a double-pass technique between a group with accommodation insufficiency (AI) and a control group and to explore the diagnostic capabilities of this new tool in comparison to conventional procedures. Methods: Retrospective cross-sectional case-control phase 1 study. Two groups age ranging from 8 to 18 years were recruitment: AI and control group. The diagnostic criterion of AI was based on monocular accommodative amplitude (AA) 2 D below Hofstetter’s calculation for minimum AA and monocular accommodative facility (MAF) failing with minus lens and cut-off at ≤ 6 cycles per minute. Accommodative response with a double pass device (HD Analyzer, Visiometrics) was measured, performing an evaluation from +1.00 D to −3.50D (−0.5D steps), offering the width of the profile at 50% (WP) in minutes of arc. Results: Differences were found between groups for the AA, MAF and MEM retinoscopy (p < 0.0001, p < 0.001, p = 0.037). The discriminative capacity of MEM retinoscopy for AI diagnosis was significant and the cut-off that maximized the sensitivity and specificity was > 0.5 D. Considering WP 50% in different points, the discriminative AI diagnosis capacities for the points of 2.0 D and 2.50 D were significant (ROC-AUC 0.78; p = 0.03 and p = 0.02). Conclusions: Double-pass system metric differed between patients with AI and control group, therefore the aim of a Phase I study was achieved. Further steps with higher sample sizes are required to evidence if the system really provides any advantage versus conventional methods in the diagnosis of AI.

PURPOSE: To evaluate whether the prediction of visual performance based on the modulation transfer function area (MTFa) calculated with optical simulations is better correlated with visual acuity or contrast sensitivity obtained from defocus curves in patients implanted with a trifocal intraocular lens. METHODS: Biometric eye data from 43 patients were used to create a mean eye model. A trifocal intraocular lens with a power obtained from the mean of the eyes implanted was incorporated into the model and the MTFa was calculated at the 11 defocus planes corresponding the 11 defocus locations measured in clinical practice. Simulations were conducted for pupil diameters of 2.5, 3, 3.5, and 4 mm. The MTFa correlation with visual acuity and contrast sensitivity was evaluated with the mean obtained after stratification of the clinical sample in four groups according to the previous pupil diameters. RESULTS: A linear model predicted the visual acuity and contrast sensitivity from MTFa with similar accuracy to nonlinear models, with R 2 approximately 0.50 for visual acuity and approximately 0.42 for contrast sensitivity. A change of −0.01 logMAR and −0.02 logC was produced per unit of MTFa for visual acuity and contrast sensitivity, respectively. The mean difference between the visual acuity and contrast sensitivity obtained from the model and that measured in clinical practice was close to zero, but the bias varied depending on the defocus lens used, with higher deviation at −0.50 and −3.00 diopters of defocus. CONCLUSIONS: The MTFa obtained from optical simulations can be used to predict the mean visual acuity and contrast sensitivity consistently, with contrast sensitivity being more sensitive but with higher bias. [ J Refract Surg. 2019;35(12):789–795.]

Intraocular lens (IOL) opacification is an infrequent complication of cataract surgery. Surface analysis has demonstrated that the opacification of IOLs is related to calcium or phosphate precipitation on or within the lenses, but the associated mechanisms are unknown, and the scientific literature is heterogeneous and limited to case series and retrospective studies. The purpose of this systematic review was to analyse the most frequent conditions associated with opacification of IOLs reported by studies. A search was carried out using the PubMed MEDLINE, Web of Science and Scopus databases. The quality of the studies selected was evaluated using the Pierson tool. The search provided a total of 811 articles, of which 39 were selected following the inclusion and exclusion criteria. The most common opacified lenses were hydrophilic IOLs according to our analysis. The mean time of appearance of lens opacification was 14.93 ± 17.82 months. The most frequent conditions associated with opacification of the IOLs were Descemet Stripping with Automated Endothelial Keratoplasty (DSAEK/DSEK) and diabetes mellitus (DM), followed by pars plana vitrectomy (PPV), blood hypertension (HT), and glaucoma. Concerning the quality analysis, the mean score was 7.00 ± 1.43 (scoring range from 0 to 10), indicating an acceptable quality of the case reports and retrospective studies. In conclusion, DSAEK/DSEK, DM, PPV, glaucoma and hypertension are conditions with potential risk of IOL opacification after cataract surgery, especially when implanting hydrophilic acrylic IOLs. Ministry of Economy, Industry and Competitiveness of Spain, Grant/Award Number: RYC‐2016‐20471.