Relationship between the main components of the crystalline lens and the anterior chamber depth after cataract formation.

PURPOSE: To assess the relationship between anterior chamber depth (ACD) and lens thickness (LT), as well as its three main components (anterior and posterior cortex and nucleus thickness), in cataractous and non-cataractous eyes, depending on the axial length (AxL). METHODS: Anterior and posterior cortex and nucleus thickness of the crystalline lens, ACD, and AxL were measured using optical low-coherence reflectometry in cataractous and non-cataractous eyes. They were also classified into hyperopia, emmetropia, myopia, and high myopia, depending on AxL; thus, eight subgroups were created. A minimum sample size of 44 eyes (of 44 patients) for each group was recruited. Linear models were fitted for the whole sample and each AxL subgroup to assess if there were differences in the relationships between the crystalline lens variables and ACD, including age as a covariate. RESULTS: Three hundred seventy cataract patients (237 females, 133 males) and 250 non-cataract controls (180 females, 70 males), aged 70.5 ± 9.4 and 41.9 ± 15.5 years, respectively, were recruited. The mean AxL, ACD, and LT for the cataractous and non-cataractous eyes were 23.90 ± 2.05, 24.11 ± 2.11, 2.64 ± 0.45, and 2.91 ± 0.49, 4.51 ± 0.38, 3.93 ± 0.44 mm, respectively. The inverse relationship of LT, anterior and posterior cortex, and nucleus thickness with ACD was not significantly (p ≥ 0.26) different between cataractous and non-cataractous eyes. Further subclassification of the sample depending on AxL showed that the inverse relationship between the posterior cortex and ACD was no longer significant (p > 0.05) for any non-cataractous AxL group. LT, anterior and posterior cortex, and nucleus thickness was not significantly (p ≥ 0.43) different between cataractous and non-cataractous eyes for the whole sample, and all AxL groups after adjusting for age. CONCLUSIONS: The presence of cataracts does not modify the inverse relationship of the LT, anterior and posterior cortex, and nucleus with ACD. And this relationship does not seem to depend importantly on AxL. Besides, the possible differences in LT, anterior and posterior cortex, and nucleus between cataractous and non-cataractous eyes may not be caused by lens opacification, but possibly by the progressive lens growth due to aging.

Inter-eye and postoperative prediction of vault after implantation of EVO + Visian phakic implantable collamer lens.

PURPOSE: To assess whether the postoperative outcomes of the implantation of an EVO + implantable collamer lens (ICL) in one eye can be used as a predictor of the vault of the fellow eye, and to evaluate the vault changes of the implantation in both eyes during the postoperative period. METHODS: A prospective study including 40 eyes of 20 patients with a bilateral EVO + ICL implantation was performed. Subjects were evaluated before the surgery and 1 day, 1 week and 1, 3 and 6 months postoperatively. Central vault was assessed using spectral-domain optical coherence tomography. The inter-eye and follow-up analyses were performed using lineal models and the Bland-Altman method. RESULTS: The vault of the first implanted eye at the 1-day visit highly predicts the vault of the second eye (R2 = .87; P < .001); the mean inter-eye difference was - 0.95 µm, and the superior and inferior limits of agreement were -50.27 µm and 148.37 µm, respectively. This relationship was maintained during the medium-term follow-up, not finding differences in the slopes among visits (P ≥ .09). A progressive decrease of vault was found during the follow-up (P < .001). Larger vault change 6 months after the surgery was associated with higher vault 1 day after the ICL implantation (R2 = .19;P = .005). CONCLUSION: One-day postoperative vault in the first eye can help to predict the optimal ICL sizing in the second eye. Vault tends to decrease during the first 6 months after EVO + ICL implantation. Eyes with higher initial vaults will also show larger reductions during the medium-term follow-up.

Assessment of the iridocorneal angle pigmentation and structures after the implantation of EVO+ Visian Implantable Collamer Lens.

PURPOSE: To evaluate the effect of EVO+ Visian Implantable Collamer Lens (ICL) implantation on the iridocorneal angle pigmentation and structures. METHODS: Myopic refractive surgery candidates who underwent posterior chamber EVO+ ICL implantation were evaluated preoperatively and 3 and 6 months postoperatively. High-resolution images of the iridocorneal angle (nasal, superior, temporal and inferior quadrants) were acquired during gonioscopy. A masked observer, blinded to study visits and patients' information, evaluated the angle width, apparent iris root insertion, iris configuration, and trabecular meshwork pigmentation according to the Spaeth scale in two different occasions. The intra-rater reliability was estimated using the weighted Gwet's Agreement Coefficient (AC2). Differences between visits were analyzed using the Cochran Q test or the Friedman test. RESULTS: Twenty-one patients (13 females and 8 males) aging 31.3 ± 6.3 years old were recruited. The intra-rater reliability of gonioscopy assessment was excellent for every parameter assessed (AC2 ≥ 0.97). No significant differences were found among the study visits for any quadrant in the angle width (p ≥ 0.74), apparent iris root insertion (p ≥ 0.22), iris configuration (p ≥ 0.21) and trabecular meshwork pigmentation (p ≥ 0.24). Mean pigmentation of trabecular meshwork for the four quadrants did not vary either among visits (p = 0.25). CONCLUSIONS: The EVO+ ICL implantation after uneventful procedures appears not to clinically affect the iridocorneal angle pigmentation and/or structures during a short-medium follow-up using gonioscopy assessment. The intra-rater reliability of glaucoma specialists assessing iridocorneal angle structures using gonioscopy images is very high.

Epithelial cells removed in advanced surface ablation (ASA) surgery can be used as a source of corneal samples to perform in vitro studies.

Human corneal epithelial cells are needed to study corneal pathophysiology in vitro. Due to the limitations of cell lines, the use of primary cells is highly desirable, but the scarcity of human tissues, along with ethical issues, make it difficult to accomplish all required experiments. In advanced surface ablation (ASA), the central corneal epithelium is removed and discarded. We hypothesized that ASA samples could be used to perform in vitro assays. In this study, 29 samples from patients undergoing ASA were recovered in supplemented DMEM/F12 culture medium, RIPA buffer, or RLT lysis buffer. The first aim was to determine whether cells could be maintained in culture. Although with the explant technique, tissue pieces did not attach to the culture surface, after disaggregation, cells showed high viability (90.0 ± 6.0%), attached to plates, and remained viable for up to 14 days. The second aim was to elucidate if ASA samples could be used to study protein or gene expression. Cytokeratin-3, ZO-1, Ki67, and E-cadherin protein expression were confirmed by immunofluorescence. Total protein (485.8 ± 115.8 µg) was isolated from cells in RIPA buffer, and GAPDH was detected by Western blotting, indicating that samples are adequate for protein studies. RNA (9.0 ± 3.6 µg) was isolated from samples in RLT lysis buffer, and GAPDH gene expression was studied by PCR, confirming that samples were also suitable for gene expression studies. These results suggest that samples obtained from corneal surface ablation procedures may constitute a valuable source of human cells to accomplish in vitro studies.

Monochromatic higher order aberrations in highly myopic eyes with Staphyloma.

BACKGROUND: Prevalence of high myopia is continuously increasing, thus, patients affected with staphyloma are abundant worldwide. Assessment of the quality of vision in these patients is mandatory for a proper clinical counselling, specially when undergoing surgical procedures that require intraocular lenses implantation. Thus, the purpose of the study was to assess monochromatic higher order aberrations (HOAs) in highly myopic eyes with staphyloma with or without a dome-shaped macula. METHODS: Participants underwent spectral-domain optical coherence tomography, ocular axial biometry, dual Scheimpflug photography and integrated Placido disk topography, and Hartmann-Shack wavefront analysis. Five groups were evaluated: a low-moderate myopia control group (< 6.00 diopters, n = 31) and four high myopia (≥6.00 diopters) groups: eyes without staphyloma (n = 18), eyes with inferior staphyloma (n = 14), eyes with posterior staphyloma without dome-shaped macula (n = 15) and eyes with posterior staphyloma with dome-shaped macula (n = 17). Subsequently, two new groups (including all participants) were created to assess differences between myopia with and without staphyloma. One-way analysis of covariance was performed using age and lens densitometry as covariates. RESULTS: Statistically significant (p ≤ 0.05) differences in anterior corneal fourth-order HOAs were observed between the low-moderate myopia and no-dome-shaped macula (Mean: 0.16 µm) and dome-shaped macula posterior staphyloma groups (Mean: 0.12 µm) in younger patients (≤45 years old). The same groups also showed (p ≤ 0.05) significant differences for anterior corneal primary spherical aberration (Mean: 0.19 and 0.13 µm, respectively). In addition, anterior corneal tetrafoil was significantly higher (p = 0.04) in dome-shaped macula compared to no-dome-shaped macula (Mean: 0.18 vs 0.06 µm, respectively). When all participants were grouped together, significantly lower mean anterior corneal primary spherical aberration (0.15 µm vs. 0.27 µm, p = 0.004) and higher internal primary spherical aberration (0.04 µm vs. -0.06 µm, p = 0.04) was observed in staphyloma compared to no-staphyloma myopic patients. CONCLUSIONS: Eyes with high myopia and staphyloma have less positive anterior corneal primary spherical aberration and less negative internal primary spherical aberration, suggesting that the anterior corneal surface tends to mimic in a specular fashion the posterior pole profile. This corneal behaviour appears to change in patients older than 45 years.

Clinical and tear cytokine profiles after advanced surface ablation refractive surgery: A six-month follow-up.

Neuropathic dry eye is one of the most frequently seen complications after corneal refractive surgery, however, its incidence decreases in a significant manner along the first six months postoperative, reaching between 10 and 45% incidence. However, little is known on the inflammatory status of the ocular surface during this recovery process. We aim to analyze the clinical and tear molecule concentration changes along six months after advanced surface ablation for myopia correction, in a prospective study including 18 eyes of 18 subjects who bilaterally underwent advanced surface ablation corneal refractive surgery. Clinical variables (uncorrected distance visual acuity, symptoms, conjunctival hyperemia, tear osmolarity, tear stability, corneal fluorescein staining, conjunctival lissamine staining, Schirmer test, and corneal esthesiometry) and a panel of 23 pro and anti-inflammatory cytokines/chemokines concentration in tears preoperatively and at 1, 3 and 6 months postoperatively were evaluated. We found that uncorrected distance visual acuity improved significantly from baseline at 1-month visit, symptoms improved and tear osmolarity decreased significantly from baseline at 3-month visit and there was a decrease in mechanical corneal threshold between 1-month and 3- and 6-month visits. Regarding tear molecules, IL-4, IL-5, IL-6, IL-13, IL-17A, and IFN-γ tear levels were significantly increased at all the three visits, compared to preoperative levels at V0; IL-2 and VEGF were also significantly increased at 1-month and 6-month visits, but not at 3-month visit, whereas IL-9 IL-10 and IL-12 were only significantly increased at 6-month visit. Although we found that there is a recovery in clinical variables at 6 months postoperatively (i.e. neuropathic dry eye was not developed in the sample), ocular surface homeostasis is not completely restored, as it can be seen by the changes in concentration of some pro and anti-inflammatory molecules measured in tears.

Transforming growth factor beta-induced p.(L558P) variant is associated with autosomal dominant lattice corneal dystrophy type IV in a large cohort of Spanish patients.

IMPORTANCE: Rare transforming growth factor beta-induced (TGFBI) gene variants are involved in autosomal dominant corneal dystrophies (CDs) with heterogeneous clinical features. BACKGROUND: The purpose of this study was to analyse TGFBI gene variants and genotype-phenotype correlations in a cohort affected by atypical stromal CD. DESIGN: Retrospective cohort study (from May 2014 to September 2017). PARTICIPANTS: Thirty-five individuals from 10 unrelated South European families presenting atypical lattice CD (LCD) were included. METHODS: Corneal phenotypes were assessed by slit-lamp examination and optical coherence tomography (OCT). Contrast sensitivity was measured under mesopic conditions. Genomic DNA was obtained from blood samples, and all 17 TGFBI exons were screened for variants by Sanger sequencing. MAIN OUTCOME MEASURES: p.(L558P) variant of TGFBI gene. RESULTS: The p.(L558P) variant was identified in 22 members of the 10 families diagnosed with atypical LCD, characterized by late-onset and absence of recurrent erosion syndrome. OCT revealed punctiform deposits in the deep-mid stroma and normal anterior stroma. This variant was demonstrated to be transmitted with the disease according to autosomal dominant inheritance in most families. CONCLUSIONS AND RELEVANCE: To the best of our knowledge, we describe a detailed clinical characterization of the largest CD cohort carrying the TGFBI p.(L558P) variant. We propose that the atypical phenotype of this recently reported alteration can be classified as a form of LCD type IV. The results show that OCT and anterior-posterior analysis of the stromal location of the opacities, along with a genetic analysis of TGFBI, are required to ensure accurate diagnosis and management of CDs.

Comparison of specular microscopy and ultrasound pachymetry before and after cataract surgery.

PURPOSE: To compare specular microscopy (Topcon SP-3000P, Topcon Corporation, Tokyo, Japan) and ultrasound (US) technology when evaluating central corneal thickness (CCT) prior to and after phacoemulsification. METHODS: Corneal edema was assessed in phacoemulsification patients due to senile cataract by measuring CCT preoperatively and 1 day, 1 month, and 3 months postoperatively. Bland-Altman analysis was performed to assess interchangeability between pachymetry techniques for each visit. Repeated measures analysis of variance was performed to evaluate variation in CCT agreement depending on the degree of corneal edema. RESULTS: One hundred and eighteen patients aged 73.9 ± 10.1 years were recruited. Topcon SP-3000P provided significant (p < 0.0001) lower CCT values than US with and without induced corneal edema. Mean differences between CCT techniques for baseline, 1 day, 1 month and 3 months after cataract surgery were -28.9 ± 22.6, -30.5 ± 41.4, -32.3 ± 16.2 and -33.0 ± 16.9 µm, respectively. The systematic bias observed was not significantly different among the 4 visits (p = 0.59). The estimated limits of agreement (based on 1.96 standard deviation) were substantial, being 90.5, 165.8, 64.9 and 67.5 um at baseline, 1 day and 1 and 3 months. CONCLUSIONS: Topcon SP-3000P provides similar systematic bias in comparison with US technique for CCT measurements regardless of the degree of corneal edema after phacoemulsification, which should be reduced after applying a constant calibration adjustment of ∼30 µm. However, interchangeability between techniques may be still limited by the notable random measurement error.

Lack of Agreement among Electrical Impedance and Freezing-Point Osmometers.

PURPOSE: To assess the interchangeability of tear osmolarity measurements between electrical impedance and freezing-point depression osmometers and to analyze inter-eye tear osmolarity variability measured with these osmometers in healthy subjects. METHODS: Tear osmolarity was measured using the TearLab osmometer (OcuSense Inc., San Diego, CA) and the Fiske 210 microsample osmometer (Advanced Instruments Inc., Norwood, MA). We randomly selected one eye in 50 subjects (29 women, 21 men; mean age, 33.16 ± 6.11 years) to analyze whether osmolarity measurements by these osmometers were interchangeable. Both eyes of 25 patients (15 women, 10 men; mean age, 34.32 ± 6.37 years) were included to analyze inter-eye osmolarity variability. RESULTS: The mean tear osmolarity values measured with the TearLab osmometer were higher (305.22 ± 16.06 mOsm/L) than those with the Fiske 210 osmometer (293.40 ± 12.22 mOsm/L), with the intraclass correlation coefficient being 0.23 (p = 0.051). A Bland-Altman plot showed that the systems were not interchangeable because there was a systematic difference, with the limits of agreement being -17.93 to 41.57 mOsm/L. There were no statistically significant differences (p = 0.5006 and p = 0.6533, respectively) between an individual's eyes measured with either osmometer. CONCLUSIONS: Because the TearLab tear osmolarity measurements were higher than those of the Fiske 210 measurements and the limits of agreement were too wide, the two osmolarity values cannot be used interchangeably. In healthy subjects, there is no difference in tear osmolarity between right and left eyes of the same individual measured with both instruments.

New trends in quantitative assessment of the corneal barrier function.

The cornea is a very particular tissue due to its transparency and its barrier function as it has to resist against the daily insults of the external environment. In addition, maintenance of this barrier function is of crucial importance to ensure a correct corneal homeostasis. Here, the corneal epithelial permeability has been assessed in vivo by means of non-invasive tetrapolar impedance measurements, taking advantage of the huge impact of the ion fluxes in the passive electrical properties of living tissues. This has been possible by using a flexible sensor based in SU-8 photoresist. In this work, a further analysis focused on the validation of the presented sensor is performed by monitoring the healing process of corneas that were previously wounded. The obtained impedance measurements have been compared with the damaged area observed in corneal fluorescein staining images. The successful results confirm the feasibility of this novel method, as it represents a more sensitive in vivo and non-invasive test to assess low alterations of the epithelial permeability. Then, it could be used as an excellent complement to the fluorescein staining image evaluation.

Senile Cataract Formation Does Not Affect Crystalline Lens Thickness.

INTRODUCTION: Characterizing lens thickness (LT) in patients with cataracts is important for better understanding the lens aging process and for designing new intraocular lens power formulas. This study aimed to analyze the influence of common senile cataract formation on the LT, anterior (ACS) and posterior (PCS) cortex space, and nuclear thickness (NT), controlling for sex, age, and axial length. METHODS: A cross-sectional study was performed. A consecutive sample of 603 volunteers (403 women, 200 men) aged 59.1 ± 18.8 years was recruited. The standardized Lens Opacification Classification System (LOCS)-III was used to classify eyes (randomly selected) into cataractous and non-cataractous groups. Also, they were classified according to the cataract location (presence or absence of cortical, nuclear, or posterior subcapsular cataract). Optical biometry was performed to measure LT, ACS, NT, and PCS. Propensity score was used to match participants one-to-one for sex, age, and axial length. Groups were compared using the Student's t test or Yuen's test. RESULTS: The four classifications divided unmatched eyes into: 361 cataractous lenses and 242 non-cataractous, 226 cortical and 377 non-cortical cataractous, 313 nuclear and 290 non-nuclear cataractous and 242 subcapsular and 361 non-subcapsular cataractous. Before matching, cataractous eyes showed significantly higher LT (4.52 ± 0.39 vs. 3.94 ± 0.46 mm, p < 0.001), ACS (0.75 ± 0.20 vs. 0.58 ± 0.23 mm, p < 0.001), NT (3.34 ± 0.23 vs. 3.18 ± 0.25 mm, p < 0.001) and PCS (0.42 ± 0.19 vs. 0.37 ± 0.19 mm, p = 0.003). Matched lens, cortical, nuclear, and subcapsular cataract samples comprised 146, 258, 182, and 226 eyes, respectively. After matching, no significant differences were observed in LT (4.34 ± 0.37 vs. 4.33 ± 0.36 mm, p = 0.94), ACS (0.72 ± 0.20 vs. 0.76 ± 0.19 mm, p = 0.08), NT (3.31 ± 0.22 vs. 3.30 ± 0.23 mm, p = 0.24) and PCS (0.42 ± 0.19 vs. 0.43 ± 0.16 mm, p = 0.79). CONCLUSIONS: The presence of senile cortical, nuclear, and posterior subcapsular cataract have no effect on LT, ACS, NT, and PCS. Confounding factors should be controlled for when measuring LT and its main components.

Design and evaluation of a customized reading rehabilitation program for patients with age-related macular degeneration.

PURPOSE: To evaluate the efficacy of a reading rehabilitation program (RRP) specifically designed for patients with impaired central vision from age-related macular degeneration (AMD) and the impact of the program on the quality of life (QoL) and to determine any predictable reading performance improvements between visits. DESIGN: Prospective case series. PARTICIPANTS: Forty-one patients with AMD who attended to the Institute of Applied Ophthalmobiology Eye Institute. METHODS: An ad hoc-created RRP comprising 4 customized in-office training and in-home training visits over 6 weeks was undertaken by AMD patients. The RRP was based on the principle of stepwise progressive goal achievement: the difficulty of training tasks increased depending on the success obtained when performing previous easier ones. Reading performance was evaluated during each in-office training visit, and the individual's perception of his or her QoL was assessed before and after the RRP. Reading performance parameters were assessed to evaluate RRP effectiveness. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), reading speed, reading duration, near visual acuity (VA), font size, and the World Health Organization Quality of Life (WHOQOL-BREF) questionnaire scores. The effect sizes (mean differences and standard deviations) also were calculated. RESULTS: The mean distance BCVA was 0.81±0.29 logarithm of the minimum angle of resolution units. The mean near VA with the appropriate low-vision aid was 0.91±0.18 (M notation) at baseline. The mean near magnification was 4.32±1.15 at the last in-office visit. The mean reading speed, reading duration, and font size improvement after the reading rehabilitation program were 48.31±22.06 words per minute (P<0.001), 35.46±15.68 minutes (P<0.001), and -4.08±2.19 font points (P<0.001), respectively. The effect sizes of reading speed, reading duration, and font size after the last visit were 2.19, 2.26, and -1.86, respectively. The final score of each WHOQOL-BREF domain improved significantly (P≤0.004) after the RRP. The increased ability to read a smaller font size was correlated with improvement in the physical health domain score of the WHOQOL-BREF (r=0.35; P=0.04). CONCLUSIONS: This customized RRP significantly enhanced reading performance and perceived QoL in patients with AMD. The improvement between visits seemed to be consistent. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Patient-reported outcomes in Spanish patients diagnosed with bilateral age-related macular degeneration.

PURPOSE: To evaluate the patient-reported outcomes (PRO) in age-related macular degeneration (AMD) patients by using instruments for eliciting health status and vision specific issues. METHODS: PRO were assessed using the 25-item National Eye Institute Visual Function Questionnaire (NEIVFQ-25) and the Short-Form General Health Survey (SF-12). RESULTS: The mean age and corrected distance visual acuity (CDVA) in the better eye of the AMD patients were 82.53 ± 5.17 years and 0.82 ± 0.43 logMAR, respectively. The overall NEIVFQ-25 composite score was 57.89. SF-12 physical and mental component summary scores were 37.28 and 57.25, respectively. There were significant correlations (p ≤ 0.05) between CDVA and the following NEIVFQ-25 subscales: general (r = -0.73), near (r = -0.40) and distance vision (r = -0.60), role limitations (r = -0.40), social function (r = -0.48) and mental health (r = -0.38). CONCLUSIONS: Visual function is severely affected in AMD patients. It hampers their daily living without, however, deeply disturbing their social function. This may help them retain adequate mental health despite their poor physical status.

Reliability and agreement of apparent chord mu measurements between static and dynamic evaluations.

PURPOSE: To assess the repeatability and agreement of Cartesian coordinates and the length of apparent chord mu and pupil diameter measurements during static (Galilei G4) and dynamic (Topolyzer Vario) evaluations. SETTING: IOBA-Eye Institute, Valladolid, Spain. DESIGN: Case series. METHODS: 3 consecutive measurements per scenario (Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions) were performed by the same clinician. The intrasession repeatability was assessed using the within-subject SD (Sw), the precision, the coefficient of variation, and the intraclass correlation coefficient (ICC). The agreement was analyzed using repeated-measures analysis of variance and the Bland-Altman method. RESULTS: Thirty-seven healthy participants were recruited. The Sw values for chord mu parameters and pupil diameter ranged from 0.01 to 0.03 and 0.08 to 0.21, respectively. The ICC was ≥0.89 for all parameters. Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions provided significantly different measures of apparent chord mu length (0.23 ± 0.11 mm, 0.30 ± 0.10 mm, and 0.25 ± 0.11 mm, respectively, P ≤ .02), X-coordinate (-0.18 ± 0.12 mm, -0.27 ± 0.11 mm, and -0.21 ± 0.12 mm, respectively, P < .001), and pupil diameter (3.38 ± 0.50 mm, 6.29 ± 0.60 mm, and 3.04 ± 0.41 mm, respectively, P < .001). Y-coordinate values obtained by Galilei G4 and Topolyzer Vario under low mesopic conditions were significantly different (0.06 ± 0.13 mm vs 0.03 ± 0.11 mm, respectively, P = .02), in contrast to Galilei G4 and Topolyzer Vario under photopic conditions (0.05 ± 0.13 mm, P = .82) and both illumination conditions of Topolyzer Vario (P ≥ .23). CONCLUSIONS: Galilei G4 and Topolyzer Vario provide consistent measurements of apparent chord mu Cartesian coordinates and length, as well as pupil diameter; however, the measurements are not interchangeable. Ophthalmic surgeons should consider these findings when planning customized intraocular lens implantation and refractive surgery procedures.

EVO/EVO+ Visian Implantable Collamer Lenses for the correction of myopia and myopia with astigmatism.

INTRODUCTION: Intraocular lens implantation in phakic eyes for the correction of refractive error is currently a widespread procedure. The EVO and EVO+ Visian Implantable Collamer Lenses (ICL) are two of the most prevalent lenses implanted. They incorporate a central orifice to avoid the need for iridotomy. The main difference between both ICL is the higher optical diameter zone provided by the EVO+, allowing a better quality of vision at night. This review aims to provide an overview of the current ICL models available for correcting myopia and myopic astigmatism. AREAS COVERED: During the last decade, more than 100 scientific papers analyzing the performance of EVO and EVO+ lenses have been published. This review describes the objective visual performance achieved with the implantation of central hole ICL lenses and the subjective perception of the patients implanted with these lenses. In addition, the safety and the potential complications associated with undergoing an EVO and EVO+ ICL implantation have been addressed. EXPERT OPINION: Refractive surgeons and candidates to undergo ICL implantation should be aware of the excellent safety and visual outcomes provided by the implantation of central hole ICL lenses. However, future research could address minor issues currently not resolved.

Influence of decentration and tilt of Tecnis ZCB00 on visual acuity and higher order aberrations.

BACKGROUND/OBJECTIVES: To determine the influence of decentration and tilt of a pseudophakic aspheric intraocular lens (IOL) on visual acuity (VA) and higher-order aberrations (HOAs), and to analyze the agreement between pupil center/axis and iridocorneal angles center/axis when assessing IOL decentration and tilt. SUBJECTS/METHODS: A prospective interventional case series study including thirty-three patients undergoing Tecnis ZCB00 (Abbott Medical Optics) implantation. IOL decentration and tilt with respect to two reference systems (pupil and iridocorneal angles centers/axes), in cartesian (X,Y) and polar (radius/tilt, polar angle/azimuth) coordinates, were assessed with optical coherence tomography. VA and internal and ocular HOAs were evaluated. Multiple linear regression models and intraclass correlation coefficient (ICC) were computed. RESULTS: IOL decentration only showed a significant effect on internal HOAs for [Formula: see text] (R2 = 0.20, P = 0.04). IOL decentration with respect to the pupil center showed a significant effect on ocular [Formula: see text] (R2 = 0.18, P = 0.05), [Formula: see text] (R2 = 0.36, P = 0.001) and [Formula: see text] (R2 = 0.24, P = 0.02); and with respect to the center of iridocorneal angles, on ocular [Formula: see text] (R2 = 0.21, P = 0.03), [Formula: see text] (R2 = 0.32, P = 0.003), primary coma (R2 = 0.41, P < 0.001), and coma-like (R2 = 0.40, P = 0.001). Poor agreement between both reference systems was found for IOL decentration measurements (ICC ≤ 0.41), except for the polar angle coordinate (ICC = 0.83). Tilt measurements showed good agreement (ICC ≥ 0.75). CONCLUSIONS: Tecnis ZCB00 decentration and tilt values after uneventful implantation appear not to have influence on VA, and their effect on HOAs are not high enough to clinically affect quality of vision. Pupil and iridocorneal angles used as reference systems may be interchangeable for IOL tilt measurements, but not for decentration.

Hyaluronan receptors in the human ocular surface: a descriptive and comparative study of RHAMM and CD44 in tissues, cell lines and freshly collected samples.

The purpose of this study was to demonstrate the presence of the receptor for hyaluronan-mediated motility (RHAMM) in human conjunctival epithelium and in two widely used cell lines from human corneal (HCE) and conjunctival (IOBA-NHC) epithelia. We compared the distribution of RHAMM proteins and mRNAs in human ocular surface tissues (corneal, limbal and conjunctival), HCE and IOBA-NHC cell lines, and corneal and conjunctival epithelia primary samples from healthy donors with the previously identified hyaluronan receptor CD44. We also aimed to determine if soluble CD44 (sCD44) was present in human tears, as it could have a role in the interaction of the tear fluid with hyaluronan. Protein expression was evaluated by Western blots and immunofluorescence microscopy. mRNA expression was evaluated by RT-PCR and Q-PCR. sCD44 was analyzed by ELISA in culture supernatants and in human tears. We describe the expression of RHAMM in human healthy conjunctiva and in HCE and IOBA-NHC cells at both protein and mRNA levels, and the presence of sCD44 in human tears. Furthermore, we detected CD44 and sCD44 expression variations in in vitro inflammatory conditions. This study also focused on the necessary caution with which the conclusions extracted from cell lines should be made, and in the great value of using primary samples as often as possible.

Can we measure mesopic pupil size with the cobalt blue light slit-lamp biomicroscopy method?

BACKGROUND: The aim of this work is to assess a previously described slit-lamp biomicroscopy-based method (SLBM) for measuring pupil diameter and compare it to Colvard infrared pupillometry (CIP). METHODS: Two examiners performed three repeated measurements with each instrument in 40 healthy eyes. We determined the agreement of SLBM and CIP, intraobserver and interobserver repeatabilities, and interobserver concordance (kappa) and SLBM ability for detecting pupil sizes over 6.0 mm. RESULTS: The mean (±standard deviation [SD]) pupil diameter was 5.81 ± 0.70 mm with SLBM and 6.26 ± 0.68 mm with CIP (p = 0.01) averaging both examiner's results. Mean differences between the SLBM and CIP were -0.60 mm and -0.30 mm for each examiner using the average of the three readings (p = 0.02), and they were very similar using the first reading. Intraobserver reproducibility: the width of the 95% LoA ranged from 1.79 to 2.30 mm. The ICCs were 0.97 and 0.92 for SLBM, and 0.96 and 0.90 for CIP. Interobserver reproducibility: the width of the LoA ranged from 1.82 to 2.09 mm. Kappa statistics were 0.39 and 0.49 for the first and mean SLBM readings, respectively, and 0.45 for both the first and mean CIP readings. Sensitivity and specificity of SLBM for detection of pupils larger than 6 mm ranged from 55.56% to 73.68% and from 76.19% to 95.45%, respectively. The best trade-off between sensitivity and specificity ranged from 5.4 mm to 6.2 mm. CONCLUSIONS: Although the SLBM is quite repeatable, it underestimates mesopic pupil size and shows a too wide range of agreement with CIP. SLBM shows low sensitivity in detecting pupils larger than 6 mm, which may be misleading when planning anterior segment surgery. Previous grading-consensus training strategies may increase interrater reproducibility, and compensation for the systematic underestimation could improve accuracy of the SLBM.

Mesopic Disability Glare in Stage-Two Dysfunctional Lens Syndrome.

INTRODUCTION: There is a lack of evidence about the exact deterioration of visual function associated with the age-related natural changes in the lens, particularly in intermediate (stage-2) dysfunctional lens syndrome (DLS). Standard photopic visual acuity and contrast sensitivity tests may not show the visual worsening in daily life activities, such as oncoming vehicle headlights at night. The purpose of this study was to analyze visual function under different conditions and glare sources in stage-2 DLS. METHODS: Forty patients over 49 years of age with initial bilateral lens opacification (Lens Opacities Classification System III [LOCS-III] scores up to 3), best-corrected visual acuity of 20/25 or better, and no ocular disease were evaluated. Binocular photopic and mesopic contrast sensitivity (CS) with/without halogen and xenon increasing glare sources were analyzed. Mesopic disability glare (MDG) was calculated as the difference between mesopic CS with/without the glare source. RESULTS: The median logarithmic CS (logCS) values were lower under mesopic conditions (1.05) than under photopic illumination (1.65; P < 0.001). Halogen and xenon glare further decreased mesopic CS (both, median logCS 0.75, P < 0.001). The mean MDG was 0.31 ± 0.10 log units for halogen glare and 0.33 ± 0.09 log units for xenon glare. The mesopic CS and MDG were not associated with any photopic test. The mesopic CS with glare but not photopic CS or mesopic CS was correlated with the LOCS-III scores. The best association was provided by MDG, which showed a pooled correlation with LOCS-III nuclear opalescence (r = 0.411, P < 0.001) and cortical scores (r = 0.226, P = 0.04). CONCLUSION: The mesopic CS under a glare source is an independent early indicator of visual impairment in stage-2 DLS patients, and appears to be substantial. Furthermore, the MDG is more sensitive than photopic and mesopic CS for evaluating patients with initial phacosclerosis. Surgeons should consider this in the decision-making process of the correct timing for lens surgery.