We aimed to summarize the outcomes reported following the implantation of the V4c implantable collamer lens with a central port (ICL, STAAR Surgical Inc) for myopia correction. A literature search in PubMed, Web of Science and Scopus was carried out to identify publications reporting clinical outcomes of patients who were implanted with the V4c ICL model and had a follow-up period of at least 6 months. A total of 35 clinical studies published between 2012 and 2020 were included in the present review. A comprehensive analysis of the available data was performed, focusing on visual and refractive outcomes at different time-points post-surgery. In addition, adverse events and other parameters such as endothelial cell density, intraocular pressure and vault measurements-which were evaluated in some of the studies-were also compared. This review encompassed a total of 2904 eyes. The outcomes reported in this review lead us to conclude that ICL V4c implantation for myopia correction is a safe and efficient procedure, with stable visual and refractive outcomes and low adverse event rates. The patient's anterior segment should be thoroughly characterized, and the ICL parameters should be carefully selected so as to achieve good outcomes and avoid complications.

Purpose: To evaluate the agreement between different parameters obtained with 2 swept-source optical coherence tomography (SS-OCT)-based biometers and 1 Scheimpflug camera with partial coherence interferometry (PCI). Setting: Single center, Oftalvist, Alicante, Spain. Design: Prospective case series. Methods: Biometry was performed in 49 eyes using 3 optical biometers: ANTERION SS-OCT, IOLMaster 700 SS-OCT, and Pentacam AXL PCI. Keratometry (K), J0 and J45 vectors, anterior chamber depth (ACD), central corneal thickness (CCT), white-to-white (WTW), lens thickness (LT), and axial length (AL) were measured with each device. Bland-Altman analysis was applied. Results: This study comprises 49 eyes of 49 patients. There were no statistically significant differences for K1, K2, J0 and J45 between the 3 devices (P > .9). In contrast, there was a statistically significant difference in the ACD, CCT, WTW, LT, and AL between the biometers (P < .001). Specifically, there was a statistically significant difference between ACD, CCT, and WTW values for all-pairwise comparisons. IOLMaster showed the shortest ACD value and ANTERION showed the largest ACD. IOLMaster showed the highest CCT and Pentacam showed the lowest CCT. IOLMaster showed the largest WTW and Pentacam showed the shortest WTW. The LT measured with IOLMaster was thicker than that measured with ANTERION. There was a statistically significant difference in the AL between IOLMaster and Pentacam, with a shorter AL measured with IOLMaster (P < .001), but no differences were found between ANTERION and IOLMaster (P = .599) and between ANTERION and Pentacam (P = .054). Conclusions: Mean differences and the limits of agreement obtained in all-pairwise comparisons of the different parameters should be judged clinically to consider the interchangeability of these devices.

SS-OCT–based biometers provide repeatable and reproducible measurements in different ocular parameters. Optical biometers based on this technology are likely to become the gold standard for ocular biometry.

Purpose To assess the interchangeability of different devices for measuring white-to-white (WTW) distance. Methods WTW distance was measured in 53 eyes of 53 patients using Anterion swept-source optical coherence topographer (SS-OCT), IOLMaster 700 SS-OCT, Pentacam HR Scheimpflug and Cassini color LED. Statistical analysis was done by means of the Friedman test and the post hoc Tukey test. The Bland-Altman analysis was applied to carry out pairwise comparisons with the average difference, 95% confidence interval of the average difference and limits of agreement 95% (LoA). Results WTW values obtained by the Anterion, IOLMaster 700, Pentacam HR and Cassini were: 11.84 ± 0.41 mm, 11.96 ± 0.41 mm, 11.68 ± 0.38 mm and 12.65 ± 0.52 mm, respectively. Statistically significant differences were found in all pairwise comparison (p \ 0.001). The lowest mean difference was found between the Anterion and IOLMaster 700 (-0.11 mm) and the highest between the Pentacam HR and Cassini (-0.96 mm). The widest LoA ranges were those that compared any device with the Cassini. LoA ranges when the other three devices were compared among them were similar: Anterion versus IOLMaster 700, Anterion versus Pentacam HR and IOLMaster versus Pentacam HR (about 0.2 mm). Conclusions Our results show that there were statistically significant differences in WTW measurement among the four devices, but under a clinical point of view, we believe that Anterion and IOLMaster 700 may be considered interchangeable and so Anterion and Pentacam HR, however, IOLMaster 700 and Pentacam HR may not and neither is Cassini with any of the other three devices.

Background: To measure angle-to-angle (ATA) and spur-to-spur (STS) distances along six meridians using highresolution swept-source optical coherence tomography (SS-OCT) and to compare those values with horizontal white-to-white (WTW) distance. Methods: 68 eyes from 68 patients were quantitatively assessed with the Anterion SS-OCT (Heidelberg Engineering, Heidelberg, Germany). ATA and STS distances were measured with the SS-OCT's B-Scan in six cross-sectional images corresponding to the vertical (6-12 o'clock), 1-7 o'clock, 2-8 o'clock, horizontal (3-9 o'clock), 4-10 o'clock and 5-11 o'clock meridians. WTW was measured horizontally with the device's infrared camera. A Pearson correlation analysis was carried out to compare ATA and STS distances with WTW. Results: The largest values were found for the vertical meridian and the shortest for the 2-8 o'clock meridian, both for ATA and STS distances. No statistically significant differences were found between WTW, ATA and STS along the horizontal meridian (p > 0.1). However, ATA and STS showed statistically significant differences elsewhere, except for the horizontal and the 2-8 o'clock meridians (p > 0.05). Moreover, we found that ATA and STS varied significantly depending on the meridian being assessed, except for ATA at 4-10 versus 3-9 o'clock and for STS at 4-10 versus 3-9 o'clock and at 3-9 versus 2-8 o'clock (p > 0.1). R 2 values ranged from 0.49 to 0.75 for ATA and STS at the different meridians, showing the best correlation at 3-9 o'clock meridian (0.64 and 0.75, respectively) and the worst at 6-12 o'clock meridian (R 2 = 0.49 for both ATA and STS). Conclusions: ATA and STS distances vary radially, thus showing that the anterior chamber is vertically oval. Therefore, it is advisable to measure these two distances along the meridian to be used.

No abstract

Introduction:To analyze the effects of PRE-SERFLO on corneal endothelial cell density (ECD). Methods: Forty-six eyes that underwent PRE-SERFLO implantation were followed up for 12 months. Specular microscopy was performed preoperatively and at 1, 3, 6, and 12 months postoperatively to measure central ECD and mean monthly reduction (MMR). Anterior segment optical coherence tomography (AS-OCT) was applied to measure the tube-endothelium (TE \ 200 lm, 201-500 lm, [ 500 lm) distance. The relationship between TE distance and ECD was analyzed with a linear mixed-effects model. Results: Central ECD decreased significantly at 1 year (7.4%, p = 0.04), with an MMR of -15 ± 25 cells/mm 2 . Regarding TE distance groups, there was an 18% ECD reduction in the \ 200 lm group vs. 1% in the [ 500 lm group (p = 0.08). Endothelial cell loss was related to TE distance (mean 482.9 ± 238 lm), with a higher rate at 1 month in comparison to 12 months for the same tube position in the anterior chamber (-174.8 ± 65.2 cells/mm 2 at 1 month vs. 30.2 ± 11.3 cells/mm 2 at 12 months, p \ 0.01). From month 6, tubes located [ 600 lm from the endothelium showed EC loss close to zero. Conclusions: The PRESERFLO implant is associated with a loss of EC from the immediate postoperative period that continues over time at lower rates. A shorter TE distance appears to cause more severe ECD loss.

Purpose: The aim of this study was to evaluate the repeatability of several corneal parameters provided by a high-resolution swept-source optical coherence tomographer (SS-OCT). Methods: One eye from each of 74 patients was measured five times consequently using the ANTERION SS-OCT. The following corneal parameters were analyzed: average, steep and flat keratometry (K), astigmatism for anterior, posterior and total at 3-mm, average K and astigmatism at 6-mm, anterior and posterior eccentricity, higher-order aberrations (HOA) and spherical aberration ([Formula: see text]), and anterior and posterior best-fit sphere at 8-mm. The intrasubject standard deviation (Sw), coefficient of variation (CoV), coefficient of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated for each parameter to assess the repeatability. Results: We have not found statistically significant differences between repeated measurements ( p > 0.05). Repeatability was good considering the different metrics used. Sw values were <0.09, varying from 0.035 (posterior average K at 6-mm) to 0.0878 (anterior flat K at 3-mm). CoV values were also low and similar among the different parameters (from 0.08% to 0.21%), except for anterior, posterior and total astigmatism (from 2.25% to 8.46%). Both anterior and posterior eccentricity, and corneal aberrations (HOA and [Formula: see text]) CoV values were also high. The CoR values were low for all parameters showing those related to the posterior cornea the lowest values (about 0.01). ICC values were >0.98. Conclusions: The ANTERION SS-OCT showed good repeatability when reconstructed different parameters for the whole cornea. This device produces measurements with high repeatability that could be useful for clinical research.