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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.

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 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.

(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 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

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 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 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.]

Over the last years it the amount of biomedical information published has reached an unstoppable progression. One ophthalmologist fully dedicated would only reach a very little proportion of the information published, during his working day.