What Are the Dry Eye Questionnaires Available in the Scientific Literature Used for? A Scoping Review.

PURPOSE: Dry eye disease (DED) is a frequent chronic ophthalmic condition. Its diagnosis includes tests and patient reported outcomes (PRO) questionnaires. Although many PRO dry eye questionnaires (PRO-DEQs) are available, they differ greatly from each other and not all have been validated. The purpose of this study was to retrieve the PRO-DEQs present in the scientific literature by performing a descriptive analysis of them and identifying those with known validity and reliability characteristics and to perform a descriptive analysis of the geographic area, year of publication, and characteristics of the target population of the clinical studies that have used validated PRO-DEQs. DESIGN: Scoping review of the literature. METHODS: Searches were conducted in PubMed to retrieve PRO-DEQs published up to July 2018 and written in English, French, Italian or Spanish. RESULTS: One thousand six hundred two records were identified and 973 were included in the final analysis. Of these, 56 provided information on the design and validation of PRO-DEQs and 49 PRO-DEQs were identified. Twenty-two PRO-DEQs were validated (17 original and 5 modified) and 27 had no associated design, validity, and reliability studies. Most of the validated PRO-DEQs were designed in English, the number of items varies from 1 to 57, the dimensions are generally not specified, and they are self-administered. The greatest use of validated PRO-DEQs in clinical studies has been in Asia since 2010, with the Ocular Surface Disease Index being the most used. These questionnaires have been used mostly in adults, retired professionals, and people with visual diseases to diagnose DED. CONCLUSIONS: This study aims to encourage the use of validated PRO-DEQs to guarantee the quality of the results obtained and the comparability and replicability among studies.

Patient selection to optimize near vision performance with a low-addition trifocal lens / Selección del paciente para optimizar el rendimiento visual en visión próxima con una lente trifocal de baja adición

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 (mi). 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 mi 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 (mi). 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 mi 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

Patient selection to optimize near vision performance with a low-addition trifocal lens.

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.

New Approach for the Calculation of the Intraocular Lens Power Based on the Fictitious Corneal Refractive Index Estimation.

PURPOSE: To identify the sources of error in predictability beyond the effective lens position and to develop two new thick lens equations. METHODS: Retrospective observational case series with 43 eyes. Information related to the actual lens position, corneal radii measured with specular reflection and Scheimpflug-based technologies, and the characteristics of the implanted lenses (radii and thickness) were used for obtaining the fictitious indexes that better predicted the postoperative spherical equivalent (SE) when the real effective lens position (ELP) was known. These fictitious indexes were used to develop two thick lens equations that were compared with the predictability of SRK/T and Barrett Universal II. RESULTS: The SE relative to the intended target was correlated to the difference between real ELP and the value estimated by SRK/T (ΔELP) (r = -0.47, p=0.002), but this only predicted 22% of variability in a linear regression model. The fictitious index for the specular reflection (n k) and Scheimpflug-based devices (n c) were significantly correlated with axial length. Including both indexes fitted to axial length in the prediction model with the ΔELP increased the r-square of the model up to 83% and 39%, respectively. Equations derived from these fictitious indexes reduced the mean SE in comparison to SRK/T and Barrett Universal II. CONCLUSIONS: The predictability with the trifocal IOL evaluated is not explained by an error in the ELP. An adjustment fitting the fictitious index with the axial length improves the predictability without false estimations of the ELP.

Standard Clinical Outcomes With a New Low Addition Trifocal Intraocular Lens.

PURPOSE: To evaluate the standard clinical outcomes, defocus curves, and satisfaction obtained with a new diffractive low addition trifocal intraocular lens (IOL). METHODS: Thirty patients who were implanted with the Versario Multifocal 3F IOL (Valeant Med Sp.zo.o., Warsaw, Poland) were recruited for a prospective observational study at Qvision, Vithas Virgen del Mar Hospital, Almería, Spain. Variables for reporting standard outcomes were collected at the 1-month visit for monocular vision and the 3-month visit for binocular vision, including best spectacle refraction and corrected and uncorrected visual acuities at far, intermediate (67 cm), and near (40 cm) distances. In addition, monocular and binocular visual acuity defocus curves were measured and questionnaires for grading subjective visual quality, satisfaction, and visual function were supplied at the end of the follow-up. RESULTS: Monocular corrected distance visual acuity decreased progressively from far (-0.05 logMAR) to near (0.25 logMAR) and improved approximately -0.1 logMAR along the defocus curve in binocular vision. The mean residual spherical equivalent (SE) was 0.15 ± 0.47 diopters (D), with 79% of eyes within ±0.50 D and 97% within ±1.00 D with the SRK/T formula. All of the visual function tasks improved after surgery, especially driving at night, which increased from 58 to 79 (P < .05). Of 27 patients, 84.4% were satisfied or very satisfied with their general vision. CONCLUSIONS: This new lens was similar in terms of visual performance and satisfaction to other trifocal IOLs. It can be classified as a trifocal extended depth of focus IOL because of the performance between extended depth of focus IOLs and medium-high addition trifocal IOLs. [J Refract Surg. 2019;35(4):214-221.].

Confounding sizing in posterior chamber phakic lens selection due to white-to-white measurement bias.

PURPOSE: To assess the agreement in the white-to-white (WTW) measurement with two different devices, the reproducibility and the probability of confusing sizing (PCS) in selecting a different implantable collamer lens (ICL). STUDY DESIGN: Retrospective observational case series. METHODS: Images of 192 eyes were captured with both devices. The WTW was measured automatically (OA) and manually (OM) with the Orbscan and Keratograph (KA and KM) by one examiner who repeated a total of four measures. A second examiner conducted a single manual measure for each device over the same image. The ICL sizing was computed for each measure of WTW and the PCS was calculated as the percentage of cases for which the confronted or repeated measure resulted in a different size of the ICL. The critical WTWs with highest PCS were identified. RESULTS: KM overestimated the WTW versus OM in 0.13 ± 0.18 mm (P < 0.001) but not in the automated method comparison, 0.01 ± 0.19 mm (P = 0.58). Inter-examiner reproducibility (R) was higher with OM than with KM, and the intra-examiner R decreased with the average of two measures in both cases. The PCS was higher with the increase of mean differences, the limits of agreement (LoAs), and R. WTWs from 11.1 to 11.2 mm, 11.6 to 11.7 mm, and 12.3 to 12.4 mm resulted in higher PCS. CONCLUSION: The mean difference is not enough to apply conversions between devices and the LoAs and R should be considered. Special attention should be taken for WTWs with higher PCS.

Prediction of surgically induced astigmatism in manual and femtosecond laser-assisted clear corneal incisions.

PURPOSE: To assess the surgically induced astigmatism with femtosecond laser-assisted and manual temporal clear corneal incisions and to evaluate the performance of a model for prediction of the surgically induced astigmatism based on the preoperative corneal astigmatism. METHODS: Clinical data of 104 right eyes and 104 left eyes undergoing cataract surgery, 52 with manual incisions and 52 with femtosecond laser-assisted incisions in each eye group, were extracted and revised retrospectively. In all cases, manual incisions were 2.2 mm width and femtosecond incisions were 2.5 mm width, both at temporal location. A predictive model of the surgically induced astigmatism was obtained by means of simple linear regression analyses. RESULTS: Mean surgically induced astigmatisms for right eyes were 0.14D@65° (manual) and 0.24D@92° (femtosecond) (p > 0.05) and for left eyes, 0.15D@101° (manual) and 0.19D@104° (femtosecond) (p > 0.05). The orthogonal components of the surgically induced astigmatism (XSIA, YSIA) were significantly correlated (p < 0.05) with the preoperative orthogonal components of corneal astigmatism (Xpreop, Ypreop) (r = -0.29 for X and r = -0.1 for Y). The preoperative astigmatism explained 8% of the variability of the XSIA and 3% of the variability of YSIA. The postoperative corneal astigmatism prediction was not improved by the surgically induced astigmatism obtained from the model in comparison with the simple vector subtraction of the mean surgically induced astigmatism. CONCLUSION: Temporal incisions induce similar astigmatism either for manual or for femtosecond procedures. This can be clinically negligible for being considered for toric intraocular lens calculation due to the great standard deviation in comparison with the mean. The usefulness of the prediction model should be confirmed in patients with high preoperative corneal astigmatism.

From Presbyopia to Cataracts: A Critical Review on Dysfunctional Lens Syndrome.

Dysfunctional lens syndrome (DLS) is a term coined to describe the natural aging changes in the crystalline lens. Different alterations in the refractive properties and transparency of the lens are produced during the development of presbyopia and cataract, such as changes in internal high order aberrations or an increase in ocular forward scattering, with a potentially significant impact on clinical measures, including visual acuity and contrast sensitivity. Objective technologies have emerged to solve the limits of current methods for the grading of the lens aging, which have been linked to the DLS term. However, there is still not a gold standard or evidence-based clinical guidelines around these new technologies despite multiple research studies have correlated their results with conventional methods such as visual acuity or the lens opacification system (LOCS), with more scientific background around the ocular scattering index (OSI) and Scheimpflug densitometry. In either case, DLS is not a new evidence-based concept that leads to new knowledge about crystalline lens aging but it is a nomenclature change of two existing terms, presbyopia and cataracts. Therefore, this term should be used with caution in the scientific peer-reviewed literature.

Biometric Factors Associated with the Visual Performance of a High Addition Multifocal Intraocular Lens.

Purpose/Aim: To evaluate the impact of ocular parameters on the visual performance achieved with the multifocal intraocular lens (IOL) Bi-Flex M 677MY. MATERIALS AND METHODS: About 26 subjects were included in the current study. Several physiological variables were retrieved from the 3-month follow-up visit, including pupil diameter and distance from pupil center to the vertex normal of the anterior cornea (µ). These variables were also obtained in the preoperative visit. Binocular and monocular visual acuity defocus curves were measured at 1 and 3 months after surgery, respectively. The monocular Area Under the Curve (AUC) was computed along the total range (Total Area Under the Curve (TAUC), +1.00 to -4.00 D) and for the ranges of Far (Far Area Under the Curve (FAUC), +0.50 to -0.50 D), (Intermediate Area Under the Curve (IAUC), -1.00 to -1.50 D) and Near vision (Near Area Under the Curve (NAUC), -2.00 to -4.00 D). Correlations between these areas and the postoperative physiological variables were assessed. RESULTS: The mean µ was reduced from 0.21 to 0.10 mm after surgery, as well as pupil diameters, either photopic (-7.4%) or mesopic (-8.1%) (p < 0.05). The mean AUCs were 2.08 ± 0.74 for TAUC, 0.57 ± 0.17 for FAUC, 0.16 ± 0.09 for IAUC, and 0.81 ± 0.29 for NAUC. Significant correlations were found between NAUC and corneal power  (r = -0.39, p = 0.05) as well as between IAUC and temporal decentration of the lens from vertex normal (ρ = -0.41, p = 0.04). CONCLUSIONS: The visual performance at near distance with the IOL evaluated improved in eyes with less corneal power. On the other hand, a slight temporal IOL decentration from vertex normal also improved intermediate visual acuity. The binocular defocus curve was similar to other trifocal IOLs.

Corneal biomechanics after laser refractive surgery: Unmasking differences between techniques.

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.

Agreement and repeatability of objective systems for assessment of the tear film.

PURPOSE: To assess the agreement and repeatability of two objective systems for measuring the tear film stability. METHODS: Retrospective analysis of the tear film stability of 99 healthy right eyes measured with a videokeratoscope (VK) and the Optical Quality Analysis System (OQAS, Visiometrics). Two consecutive measures were taken with both systems, with an interval of 10 min between them. Variables included in the study were first and mean non-invasive break-up times (NIBUT and MNIBUT) measured with VK, and mean and standard deviation of the optical scattering index (OSIm and OSIsd) measured with OQAS. The agreement and repeatability of grading scales provided by both devices were also evaluated using the Cohen's k with quadratic weights. The Ocular Surface Disease index (OSDI) questionnaire was also passed out to all subjects. Correlations and associations between subjective and objective metrics were analyzed. RESULTS: Significant differences were found between consecutive measurements of NIBUT (p = 0.04) and MNIBUT (p = 0.01), but not for OSIm (p = 0.11) and OSIsd (p = 0.50). Grading scales resulted in fair (k = 0.20) or poor agreement (k = 0.04) between systems depending if the first or second trial was considered. The repeatability of the grading scale was good for OQAS (k = 0.59) and fair for VK (k = 0.37). No significant correlations or associations were found between OSDI and any of the metrics obtained with both devices (p ≥ 0.36). CONCLUSIONS: The two devices evaluated cannot be used interchangeably for the assessment of tear film stability. Good intrasession repeatability was obtained for tear film grading of the OQAS whereas it was fair for VK.

Ocular surface and tear film status among contact lens wearers and non-wearers who use VDT at work: comparing three different lens types.

PURPOSE: To analyze differences in the ocular surface appearance and tear film status of contact lens wearers and non-wearers in a group of visual display terminals (VDT) workers and additionally to assess differences between lens materials. METHODS: Cross-sectional study of 236 office workers, of whom 92 were contact lens wearers. Workers provided information on their contact lenses (conventional hydrogel, silicone hydrogel or rigid gas permeable lenses) and exposure to VDT at work. Ocular surface and tear film status were determined by the presence of bulbar, limbal and lid redness, lid roughness and corneal staining type, and by Schirmer's and tear break-up time tests (TBUT). A generalized linear model was used to calculate the crude (cRR) and age- and sex-adjusted (aRR) relative risk to measure the association between ocular surface and tear film abnormalities and contact lens use and type. RESULTS: The aRR of ocular surface abnormalities was higher in contact lens wearers compared to non-wearers: bulbar redness (aRR 1.69; 95% CI 1.25-2.30), limbal redness (aRR 2.87; 1.88-4.37), lid redness (aRR 2.53; 1.35-4.73) and lid roughness (aRR 7.03; 1.31-37.82). VDT exposure > 4 h/day increased wearers' risk of limbal and lid redness. Conventional hydrogel wearers had the highest risk of ocular surface abnormalities, followed by silicone hydrogel wearers. Both contact and non-contact lens wearers had a high prevalence of altered TBUT (77.3 and 75.7% respectively) and Schirmer (51.8 and 41.3%). CONCLUSIONS: Regular contact lens use during VDT exposure at work increases risk of bulbar, limbal and lid redness, and lid roughness, especially in soft contact lens wearers. The high prevalence of altered TBUT and Schirmer's results in all participants suggests that VDT use greatly affects tear film characteristics.

New parameters for evaluating corneal biomechanics and intraocular pressure after small-incision lenticule extraction by Scheimpflug-based dynamic tonometry.

PURPOSE: To evaluate parameters and dynamic corneal densitometry with a new dynamic Scheimpflug analyzer (Corvis ST) in eyes having small-incision lenticule extraction (SMILE). SETTING: Qvision, Vithas Virgen del Mar Hospital, Almería, Spain. DESIGN: Retrospective case series. METHODS: The study comprised eyes from the same institution having small-incision lenticule extraction surgery. Preoperative and 1-month postoperative measurements were taken. RESULTS: Forty-three eyes were evaluated. The mean difference in intraocular pressure (IOP) and biomechanically corrected IOP before and after surgery was 2.24 mm Hg ± 1.26 mm (SD) (P = .001) and 0.57 ± 1.77 mm Hg (P = .04), respectively. All dynamic Scheimpflug analyzer parameters changed significantly after surgery (P < .05). The variation in each parameter was correlated with the removed corneal thickness (P < .05), except the stiffness parameter at the first applanation (P = .15). None of the 4 dynamic corneal densitometry parameters changed significantly as a result of surgery (P ≥ .29). A new sign, described as an inclined brightness fringe moving through the corneal periphery, appeared preoperatively in eyes with higher dynamic corneal densitometry. This sign was more prevalent postoperatively (48.8% versus 72.1%) (P = .04). CONCLUSIONS: The biomechanically corrected IOP measured after surgery with the dynamic Scheimpflug analyzer showed better agreement with the preoperative values than IOP. The stiffness parameter was not dependent on the amount of removed corneal thickness. A new sign correlated with dynamic corneal densitometry was found and might be related to changes in corneal hydration and biomechanics.

Corneal Thickness After SMILE Affects Scheimpflug-based Dynamic Tonometry.

PURPOSE: To evaluate the corneal biomechanical changes due to small incision lenticule extraction (SMILE) measured by Scheimpflug-based dynamic tonometry and to assess the impact of the corneal thickness. METHODS: Sixty-eight patients measured with the Corvis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany) preoperatively and 1 month after SMILE were included in this retrospective observational study. Patients were divided into three groups depending on the preoperative spherical equivalent: low from -1.00 to -3.00 diopters (D), medium from -3.25 to -5.00 D, and high from -5.25 to -7.25 D. Changes in Corvis ST parameters due to the surgery were analyzed and new indexes for correcting the impact of corneal thickness were proposed. RESULTS: First and second applanation times changed after SMILE (P < .0001) but no differences were found in the comparison between these relative changes (P = .31). First applanation time was correlated with central corneal thickness (r = 0.368, P = .002) but not second applanation time (r = -0.149, P = .23). The change in first applanation time due to SMILE was different among myopic groups (P = .007) but equal when a new index that considers the removed central corneal thickness was used for comparison (P = .31). Deformation amplitude was also increased after SMILE (P < .0001), but after subtracting the removed corneal thickness from the postoperative deformation amplitude the result was equal to the preoperative deformation amplitude (P = .26). CONCLUSIONS: SMILE produces significant changes in the Corvis ST parameters of time and deformation amplitude, but these changes are mainly explained by the confounding variable of corneal thickness. [J Refract Surg. 2016;32(12):821-828.].

Effect of contact lens use on Computer Vision Syndrome.

PURPOSE: To analyse the relationship between Computer Vision Syndrome (CVS) in computer workers and contact lens use, according to lens materials. METHODS: Cross-sectional study. The study included 426 civil-service office workers, of whom 22% were contact lens wearers. Workers completed the Computer Vision Syndrome Questionnaire (CVS-Q) and provided information on their contact lenses and exposure to video display terminals (VDT) at work. CVS was defined as a CVS-Q score of 6 or more. The covariates were age and sex. Logistic regression was used to calculate the association (crude and adjusted for age and sex) between CVS and individual and work-related factors, and between CVS and contact lens type. RESULTS: Contact lens wearers are more likely to suffer CVS than non-lens wearers, with a prevalence of 65% vs 50%. Workers who wear contact lenses and are exposed to the computer for more than 6 h day(-1) are more likely to suffer CVS than non-lens wearers working at the computer for the same amount of time (aOR = 4.85; 95% CI, 1.25-18.80; p = 0.02). CONCLUSIONS: Regular contact lens use increases CVS after 6 h of computer work.