Clinical outcomes of a modified ophthalmic viscosurgical device-free implantable collamer lens implantation.

PURPOSE: To investigate the efficacy and safety of a modified dual-incision ophthalmic viscosurgical device-free (OVD-free) method for implantable collamer lens (ICL) implantation in high myopic eyes. METHODS: A total of 68 participants were enrolled in this prospective randomized clinical trial, including 33 in the OVD-free group and 35 in the standard group. Operation time and intraocular pressure (IOP) at 2 hours postoperatively were recorded. Visual acuity, refractive power, IOP, corneal endothelium parameters, and anterior segment parameters were assessed at 1 day, 1 week, 1 month, 3 months, and 6 months postoperatively. Postoperative subjective visual quality at 3 months was recorded through a Quality of Vision (QoV) questionnaire. RESULTS: No significant differences in visual acuity, refractive outcomes, and corneal endothelial parameters were found, while the operation time was significantly shorter in the OVD-free group. Both groups showed a significant increase in IOP at 2 hours after surgery, but the increase in the OVD-free group was significantly smaller than that in the standard group. In addition, the frequency of ring-shaped dysphotopsia in the OVD-free group (15.15%) was significantly lower than that in the standard group (40%), and the severity and annoyance of this symptom were also significantly lower in the OVD-free group. CONCLUSION: The modified OVD-free ICL implantation is a safe, effective, and predictable method for myopia correction, which could be a better choice for short surgery time, better subjective visual perception, and low occurrence of IOP elevation.

Silicone oil as a corneal lubricant to reduce corneal edema and improve visualization during vitrectomy.

AIM: To evaluate the efficacy and safety of silicone oil (SO) as a corneal lubricant to improve visualization during vitrectomy. METHODS: Patients who underwent vitreoretinal surgery were divided into two groups. Group 1 was operated on with initial SO (Oxane 5700) as a corneal lubricant. Group 2 was operated on with initial lactated ringer's solution (LRS) and then replaced with SO as required. Fundus clarity was scored during the surgery. Fluorescein staining was performed to determine the damage to corneal epithelium. RESULTS: Totally 114 eyes of 114 patients were included. Single SO use maintained a clear cornea and provided excellent visualization of surgical image. In group 1, the fundus clarity was grade 3 in 41/45 eyes and grade 2 in 4/45 eyes. In group 2, corneal edema frequently occurred after initial LRS use. The fundus clarity was grade 3 in 19/69 eyes, 2 in 37/69 eyes and 1 in 13/69 eyes (P<0.05). SO was applied in 29 eyes of initial LRS use with subsequent corneal edema, which eliminated the corneal edema in 26 eyes. Corneal fluorescein staining score in group 1 was 0 in 28 eyes, 1 in 11 eyes and 2 in 6 eyes, and 40, 20 and 9, respectively, in group 2 (all P>0.05). CONCLUSION: The use of SO as a corneal lubricant is effective and safe for preserving and improving corneal clarity and providing clear surgical field during vitrectomy.

Changes in choroidal hemodynamics of form-deprivation myopia in Guinea pigs.

PURPOSE: We studied changes in the choroid, particularly variation in blood flow, during the development of myopia. The hemodynamic mechanism in play remains unclear. We evaluated blood flow by quantitating indocyanine green (ICG) fluorescence in a guinea pig model of form-deprivation myopia. METHODS: Guinea pigs were divided into form-deprivation myopia (FDM) and normal control (NC) groups. Ocular biometric and choroidal hemodynamics parameters were quantitatively derived via ICG imaging, and included the maximal ICG fluorescence intensity (Imax), rising time (Trising), blood flow index (BFI), and mean transit time (MTT). RESULTS: Form deprivation was associated with significant interocular differences in terms of both refractive error and axial length. ICG fluorescence hemodynamic maps of fundal blood flow and vasculature density were evident. In deprived eyes, the fluorescence signals exhibited significantly longer Trising and MTT but lower Imax and BFI than fellow eyes and NC group. The interocular differences in terms of the ocular biometric and hemodynamic parameters were significantly correlated. Hemodynamic analysis of choriocapillaris lobules revealed weakened fluorescence intensity and prolonged arrival and filling times in deprived eyes. Form deprivation reduced the number of lobulated choriocapillaris structures. CONCLUSION: Form-deprivation myopia triggered changes in the hemodynamic and vascular network structures of the choroid and choriocapillaris. The ICG fluorescence imaging/analysis method provides a unique tool for further myopia research.

Association between inflammatory cytokines and oxidative stress levels in aqueous humor with axial length in human myopia.

This study investigated the content of inflammatory cytokines and oxidative stress levels in the aqueous humor (AH) of patients with high myopia (HM) and explored the relationship between these factors and the axial length (AL) of the eye, to explore the roles of mild intraocular inflammation and oxidative stress imbalance in the occurrence and development of myopia. AH samples from 40 patients (70 eyes) were collected during implantable collamer lens (ICL-V4c) surgery. The subjects were divided into three groups according to AL: group A (AL ≤ 26 mm), group B (26 < AL ≤ 28 mm), and group C (AL ≥ 28 mm). The concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2), and interleukin-1ß (IL-1ß) in the AH of the three groups were measured using the Luminex system. Oxidative stress levels were measured using reagent kits targeting total antioxidant capacity (T-AOC), catalase (CAT), and nitric oxide (NO) and malonaldehyde (MDA) content. The results showed compared with group A, IL-1ß, MMP-2, and IL-6 concentrations were significantly higher and T-AOC levels were significantly lower in group C. There were no significant differences in CAT, NO, MDA, or TNF-α levels among the groups. The concentrations of IL-6 (r = 0.379, p = 0.016), MMP-2 (r = 0.469, p = 0.002), and MDA (r = 0.354, p = 0.025) in AH were positively correlated with the AL, whereas T-AOC (r = -0.678, p = 0.000) was negatively correlated with AL. These results suggest that mild intraocular inflammation and oxidative stress imbalance may be associated with myopia. Further experiments are needed to confirm the role of mild intraocular inflammation and oxidative stress imbalance in the occurrence and development of myopia.

MicroRNA Profiling in the Aqueous Humor of Keratoconus Eyes.

Purpose: To identify differentially expressed (DE) microRNAs (miRNAs) in the aqueous humor (AH) of keratoconus (KC) eyes using next-generation sequencing and to explore whether DE miRNAs might play roles in KC pathophysiology. Methods: The small RNAs in the AH of 15 KC eyes and 15 myopia eyes (the control group) were sequenced on an Illumina NovaSeq 6000 platform. Gene Oncology and Kyoto Encyclopedia of Genes and Genome enrichment analyses were performed. Receiver operating characteristic curves were used to identify potential KC biomarkers. Results: We identified 204 miRNAs in the AH of the KC group and 200 in the AH of the control group. Fourteen miRNAs were differentially expressed between the two groups; four miRNAs were upregulated and 10 downregulated in KC AH. The possible pathways regulated by the DE miRNAs included antigen processing and presentation, endocytosis, mismatch repair, and Hippo signaling. The AH concentrations of miR-222-3p, miR-363-3p, and miR-423-5p exhibited areas under the curves of 1. Conclusions: We profiled the DE miRNAs of the AH of KC eyes. These miRNAs may be associated with KC pathogenesis and could serve as KC biomarkers. Translational Relevance: Data on aberrantly expressed miRNAs in KC combined with bioinformatics analyses suggest possible roles for specific miRNAs. The DE miRNAs may serve as diagnostic KC biomarkers.

The immune-related role of beta-2-microglobulin in melanoma.

Despite the remarkable success of immunotherapy in the treatment of melanoma, resistance to these agents still affects patient prognosis and response to therapies. Beta-2-microglobulin (ß2M), an important subunit of major histocompatibility complex (MHC) class I, has important biological functions and roles in tumor immunity. In recent years, increasing studies have shown that B2M gene deficiency can inhibit MHC class I antigen presentation and lead to cancer immune evasion by affecting ß2M expression. Based on this, B2M gene defect and T cell-based immunotherapy can interact to affect the efficacy of melanoma treatment. Taking into account the many recent advances in B2M-related melanoma immunity, here we discuss the immune function of the B2M gene in tumors, its common genetic alteration in melanoma, and its impact on and related improvements in melanoma immunotherapy. Our comprehensive review of ß2M biology and its role in tumor immunotherapy contributes to understanding the potential of B2M gene as a promising melanoma therapeutic target.

Effects of low-concentration atropine eye drops on the optical quality of the eyes in myopic children.

Purpose: The present study was performed to compare the optical quality of the eyes of myopic children before and after treatment with atropine eye drops of different concentrations. Methods: In the study population of 71 patients (131 eyes), 34 patients (63 eyes) were given 0.01% atropine eye drops and 37 patients (68 eyes) were given 0.05% atropine eye drops. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs 100%, 20%, and 9%) under different lighting conditions were measured before and after two weeks of atropine treatment. Results: After using 0.05% atropine eye drops for two weeks, the Strehl ratio decreased from 0.27 ± 0.07 to 0.23 ± 0.07 (P = 0.0026), PVA 20% decreased from 1.15 ± 0.32 to 1.03 ± 0.36 (P = 0.0344), and PVA 9% decreased from 0.74 ± 0.23 to 0.64 ± 0.23 (P = 0.0073). The OSI was significantly higher after using 0.05% than 0.01% atropine eye drops (P = 0.0396), while both the Strehl ratio and PVA 20% were lower after using 0.05% than 0.01% atropine eye drops (P = 0.0087 and P = 0.0492, respectively). Conclusion: The children's optical quality did not change significantly after using 0.01% atropine eye drops, whereas it decreased after using 0.05% atropine eye drops.

Artificial intelligence improves accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor for adult refractometry.

AIM: To evaluate the accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor (hICA) with artificial intelligence (AI) by comparing its refraction measurements to those recorded using hICA and a clinical table-mounted automatic refractor (TAR). METHODS: A cross-sectional study using three optometers, including hICA with or without AI and TAR, for refractometry of adults (aged 19-49 years old) with no signs of ocular disease or trauma in the absence of cycloplegia. Right and left eye refraction data were recorded, including the spherical equivalent (SE), diopter of spherical power (DS), diopter of cylindrical power (DC) decomposed into vectors J0 and J45, and measurement times. To avoid analytical difficulties associated with the interdependence of observations between eyes from the same individual, the Generalized Estimation Equation was used to compare the SE, DS, J0 and J45 measurements, and the times thereof, among the different groups. The intraclass correlation coefficient (ICC) and Spearman's rank correlation coefficient were used to evaluate correlations among the measurements recorded by the three different instruments. Bland-Altman were used to analyze the precision of the equipment by the agreement. RESULTS: A total of 70 patients (140 eyes; mean age: 31.37y; range: 19-49y) were assessed using refractometry. In a brightly lit environment, there was no significant difference between the mean SE recorded using TAR and that recorded using hICA with AI or without AI (both P>0.05). In an intense-light environment, hICA equipped with AI showed a better detection rate than without AI. Light intensity had a greater effect on dioptric measurements recorded using hICA without AI (P<0.001) than on those recorded using the one equipped with AI (P<0.05). Measurement times varied significantly between the different light intensities and instruments (P<0.05). CONCLUSION: For the normal human eyes, AI may improve the accuracy, efficiency, and reliability of measurements recorded using hICA in various light environments.

Polyethyleneimine/hydrated titanium oxide-functionalized fibrous adsorbent for removing cobalt: Adsorption performance and irradiation stability.

Radionuclides of 60Co often encountered in the fields of radiation therapy, medical preparation, and equipment sterilization, which have been considered fatal. Therefore, developing efficient and irradiation-stable adsorbents for the removal of 60Co in wastewater is urgently needed. An irradiation-stable fibrous adsorbent was fabricated through the surface functionalization of collagen fibers (CFs) by polyethyleneimine (PEI) and hydrated titanium oxide (TiO) (PEI-TiO-CFs). PEI-TiO-CFs, including their adsorption performance and irradiation stability, were systematically investigated. Results showed that PEI-TiO-CFs exhibit a maximum adsorption capacity of 0.5575 mmol g-1. In addition, the adsorption capacity of PEI-TiO-CFs only demonstrated a slight decrease in the selectivity investigation of Co2+ mixed with another coexisting ion, such as Na+, K+, and NO3-, Cl-. Furthermore, breakthrough point of PEI-TiO-CFs in column is high at 80 BV (bed volume) and the PEI-TiO-CF column can be mostly regenerated using 12 BV of Na2EDTA solution. Excellent irradiation stability of PEI-TiO-CFs was confirmed by the maintained morphology and adsorption capacity after irradiation at 350 kGy of 60Co γ-ray. Results indicated that PEI-TiO-CFs are an effective adsorbent for radioactive cobalt removal from aqueous solutions.

Scleral remodeling in myopia development.

With the increasing prevalence in recent years, myopia has become an essential global health concern. In most instances, an increased axial length of the eye is the structural cause of nearsightedness. The scleral remodeling, primarily dependent on the scleral extracellular matrix (ECM) changes, is significantly linked to eye lengthening. Scleral remodeling plays a critical function in the incidence and progression of myopia. This mini-review will focus on recent research progress of scleral remodeling in the hope of providing new ideas for the prophylaxis and treatment of myopia.

MicroRNA-29a May Influence Myopia Development by Regulating Collagen I.

PURPOSE: The aim of this study was to characterize the regulatory role of microRNA-29a (miR-29a) in myopia, providing support for potential biomarkers and new therapeutic targets of myopia in humans. METHODS: The miR-29a expression level was detected in the aqueous humor and peripheral blood plasma of 21 high myopic patients and eight cataract control patients using quantitative polymerase chain reaction. iTRAQ analysis of proteomes was conducted to show the regulatory effect of miR-29a on human scleral fibroblasts (SFs) cultured in vitro. We also assessed proliferation, migration, and collagen I synthesis in SF cells, mediated by miR-29a. RESULTS: MiR-29a expression was significantly higher in the aqueous humor of highly myopic patients than in the cataract control patients (fold change: 4.861, p = 0.001). miR-29a inhibited the synthesis of type I collagen in human SF cells and enhanced cell migration, but had no significant effect on cell proliferation. CONCLUSION: MiR-29a was highly expressed in aqueous humor of myopia patients and inhibited the synthesis of type I collagen in human SF cells in vivo, thereby it may play an important role in myopia development.

Contribution of Total Screen/Online-Course Time to Asthenopia in Children During COVID-19 Pandemic via Influencing Psychological Stress.

Objectives: During the coronavirus disease 2019 (COVID-19) self-quarantine period, the transition to online-course has profoundly changed the learning modes of millions of school-aged children and put them at an increased risk of asthenopia. Therefore, we aimed to determine associations of the total screen/online-course time with asthenopia prevalence among that children during the COVID-19 pandemic, and whether the associations were mediated by psychological stress. Methods: Asthenopia was defined according to a validated computer vision syndrome questionnaire (CVS-Q). We used CVS-Q to collect the frequency and intensity of 16 asthenopia-related eye symptoms of 25,781 children. Demographic features, eye care habits, visual disorders, lifestyle, psychological and environmental factors, were also collected. Results: The overall asthenopia prevalence was 12.1%, varying from 5.4 to 18.2% across grade/gender-classified subgroups. A 100-h increment of total screen/online-course time were associated with an increased risk of asthenopia by 9% [odds ratio (OR) = 1.09] and 11% (OR = 1.11), respectively. Mediation analysis showed that the proportions of total effects mediated by psychological stress were 23.5 and 38.1%, respectively. Age, female gender, having myopia or astigmatism, bad habits when watching screens were also risk factors. Conversely, keeping 34-65 cm between eyes and screen, increased rest time between classes, and increased eye exercise were all associated with a decreased risk. Conclusion: Our study indicated that the influence of long total screen or online-course time on psychological stress increases asthenopia risk. The findings of this study have provided a new avenue for intervening screen-related asthenopia in addition to incorporating a reasonable schedule of online courses into educational policy.

Relationship between Axial Length and Levels of TGF-ß in the Aqueous Humor and Plasma of Myopic Patients.

PURPOSE: To investigate the levels of transforming growth factor-ß (TGF-ß) in human aqueous humor (AH) and plasma (PL) of patients with myopia, and verify whether there is an association between these levels and their association with axial length (AL). METHODS: Thirty-eight myopic patients who received intraocular collamer lens (ICL) implantation were enrolled in this cross-sectional study. Patients were divided into three groups based on AL with cut-off points of 26 and 28 mm. AH and PL samples were obtained during ICL implantation surgery. The levels of TGF-ß1, TGF-ß2, and TGF-ß3 in the AH and PL samples were measured using Luminex xMAP Technology kits (Milliplex xMAP kits). The protein levels of TGF-ßs in both AH and PL samples and their relationships with AL were analyzed. RESULTS: In all, 38 patients (59 eyes) were enrolled and divided into the three groups: group A contained 7 people (10 eyes), group B contained 22 people (37 eyes), and group C contained 9 people (12 eyes). In the AH group, we detected TGF-ß1 (P 50: 19.97 pg/mL), TGF-ß2 (2446.00 pg/mL), and TGF-ß3 (26.33 pg/mL); in PL, these concentrations were 8984.00, 523.44, and 210.47 pg/mL, respectively. The levels of TGF-ß1 and TGF-ß3 in AH were positively associated with AL. None of the three isoforms in PL were related to those in AH or to AL. CONCLUSIONS: The levels of TGF-ß1 and TGF-ß3 in AH were more strongly associated with the severity of myopia than the types of TGF-ß in PL.

Irradiation-stable hydrous titanium oxide-immobilized collagen fibers for uranium removal from radioactive wastewater.

Developing efficient adsorbents with radiation stability for uranium removal from nuclear wastewater is greatly important for resource sustainability and environmental safety in manufacturing nuclear fuel. A novel adsorbent of hydrous titanium oxide-immobilized collagen fibers (HTO/CFs) with good radiation stability for UO22+ removal was developed. Results showed that the adsorption capacity of HTO/CFs for UO22+ was 1.379 mmol g-1 at 303 K and pH 5.0 when the initial concentration of UO22+ was 2.5 mmol L-1. Moreover, HTO/CFs showed high selectivity for U(VI) in bilateral mixed solution including UO22+ with another coexisting ion, such as Cl-, NO3-, Zn2+, and Mg2+. The adsorption behavior of UO22+ from radioactive wastewater on HTO/CF column was also investigated, and the breakthrough point was approximately 250 BV (bed volume). Notably, the HTO/CFs column can be rapidly regenerated by using only 4.0 BV of 0.1 mol L-1 HNO3 solution. The regenerated HTO/CFs column exhibited slight change in the breakthrough curve, suggesting its excellent reapplication ability. Furthermore, after irradiation under 60Co γ-ray at total doses of 10-350 kGy, HTO/CFs still preserved fibrous morphology and adsorption capacity, indicating significant radiation stability. These results demonstrate that HTO/CFs are industrial scalable adsorbents for the adsorptive recovery of uranium.

Association between MMP/TIMP Levels in the Aqueous Humor and Plasma with Axial Lengths in Myopia Patients.

PURPOSE: The present study investigated the profiles of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) of the aqueous humor (AH) and plasma (PL) in myopia patients, to determine whether there was an association between these levels with their axial length (AL) and to investigate if MMPs/TIMPs were regulated locally or systemically. METHODS: A cross-sectional study was conducted. Thirty-nine patients (78 eyes) diagnosed with high myopia were recruited. The AL was measured using IOL Master. And the patients were divided into three groups based on their AL, Group A (AL ≤ 26 mm), Group B (26 < AL ≤ 28 mm), and Group C (AL > 28 mm). The AH in both eyes and blood samples were collected before the patients underwent implantable collamer lens surgery. In all, 78 samples of the AH and 39 samples of the PL were analyzed using MILLIPLEX map assays, followed by statistical analyses of the results. RESULTS: There were 8 patients (16 eyes) in Group A, 22 patients (44 eyes) in Group B, and 9 patients (18 eyes) in Group C. MMP-1 (p = 0.014, Β = 0.118), MMP-2 (p ≤ 0.001, Β = 0.278), MMP-9 (p ≤ 0.001, Β = 0.019), and TIMP-1 (p = 0.014, Β = 0.062) in the AH were positively associated with the AL. MMP-1 (p = 0.004, Β = 0.001) and TIMP-1 (p = 0.030, Β = 1.171) concentrations in the PL increased linearly with longer ALs. No concentration-dependent relationship was found between MMP-2 in the PL and AL. CONCLUSIONS: There was a consistent relationship between MMP-2 in the AH and AL. AL was not consistently or substantially affected by MMP-2 in the PL, indicating myopia formation was possibly a localized process. Associations among MMP-1, MMP-9, and TIMP-1 in the AH and AL were also observed.

Optical Quality of Highly Myopic Eyes under Different Lighting Conditions and Other Relevant Parameters.

Purpose: To evaluate the optical quality of highly myopic eyes under light and dark conditions and correlate it with other relevant parameters. Materials and Methods: A cross-sectional, observational study was performed on 180 eyes of 90 highly myopic patients (29 males and 61 females; mean age: 27.833 ± 0.364 years [range: 18-45 years]). The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuity (PVA; 100%, 20%, and 9%) under different lighting conditions were measured to evaluate the optical quality, which was correlated with probable relevant factors, including, axis length, spherical equivalent (SE), uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BDVA), astigmatism, and corneal curvature. The relationship between these visual parameters and optical quality was analyzed using a generalized linear model. Results: The OSIs were 1.241 ± 0.068 and 1.515 ± 0.076; the MTF cutoff frequencies were 37.725 ± 0.559 and 30.238 ± 0.550 cpd; the Strehl ratios were 0.219 ± 0.004 and 0.175 ± 0.003; and the PVAs at 100%, 20%, and 9% were 1.257 ± 0.019 and 1.001 ± 0.018, 0.949 ± 0.017 and 0.719 ± 0.015, and 0.579 ± 0.011 and 0.439 ± 0.010, under bright and dark conditions respectively. The optical quality parameters were correlated with age, SE, BDVA, corneal astigmatism, and curvature to different degrees under different lighting conditions. Conclusions: The optical quality declined in highly myopic eyes under both bright and dark lighting conditions. SE, BDVA, corneal astigmatism, and curvature were correlated with optical quality to different degrees under different lighting conditions.

microRNA profiling in the aqueous humor of highly myopic eyes using next generation sequencing.

PURPOSE: To characterize microRNAs (miRNAs) and their possible roles in high myopia by using next generation sequencing. METHODS: Aqueous humor samples were obtained from 25 highly myopic eyes and 25 cataract eyes at the onset of surgery. miRNA next generation sequencing and bioinformatics analyses were performed using RNA extracted from 30 samples. The remaining 20 samples were used for quantitative polymerase chain reaction validation of sequencing results. RESULTS: A total of 341 microRNAs were detected in the aqueous humor samples of highly myopic eyes; 201 miRNAs were detected in the aqueous humor samples of cataractous control eyes. A total of 249 mature miRNAs and 17 novel miRNAs were differentially expressed during myopia. Possible pathways regulated by these aberrantly expressed miRNAs included the TNF, MAPK, PI3K-Akt, and HIF-1 signaling pathways. The relative expression patterns of hsa-let-7i-5p, hsa-miR-127-3p, and hsa-miR-98-5p were confirmed by quantitative polymerase chain reaction. CONCLUSIONS: The current study provided an overall view of miRNA profiling in the aqueous humor of highly myopic eyes. These profiles may be associated with myopia pathogenesis, and are potential biomarkers.

Optical quality after posterior chamber Phakic implantation of an intraocular Lens with a central hole (V4c implantable Collamer Lens) under different lighting conditions.

BACKGROUND: The current study compared optical quality before and after implantation of a posterior chamber phakic intraocular lens with a central hole [V4c implantable collamer lens (ICL)] under bright and dark lighting conditions by means of the Optical Quality Analysis System™ (OQAS; Visiometrics, Terrassa, Spain). METHODS: This prospective study involved 91 eyes of 46 consecutive high myopia patients (15 males and 31 females, average spherical equivalent - 10.50 ± 0.33D) undergoing implantation of a V4c ICL. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs; 100, 20, and 9%), under different lighting conditions, were measured before and 1 week, 1 month, and 3 months after surgery. RESULTS: All optical parameters showed significant improvements, at all time points, under dark condition after surgery. We observed no significant changes in PVA 9% at 1 week (mean value 0.539, P = 0.12) or 1 month after surgery (mean value 0.573, P = 0.08) under bright condition; but all other postoperative parameters improved significantly. Comparing the two lighting conditions, the OSI decreased more under dark conditions at 1 week (P = 0.02), 1 month (P = 0.004), and 3 months (P = 0.002), but there was no significant difference in any other parameter. In addition, patients were divided into super high myopia (group S, spherical equivalent greater than - 10 D) and high myopia (group H, spherical equivalent from - 6 D to - 10 D), the group S improved significantly more than group H in all parameters, under both bright and dark conditions. CONCLUSIONS: V4c ICL implantation improved optical quality under both bright and dark lighting conditions, and had a better ability to reduce the extent of scattering in the dark. Furthermore, group S achieved greater improvement in visual quality, which should be considered by physicians before surgery.

Influence of refractive error on pupil diameters in highly myopic eyes with implantable collamer lenses.

PURPOSE: To investigate the influence of refractive error on pupil diameters in highly myopic eyes with implantable collamer lenses. SETTING: Shanghai, China. DESIGN: A prospective consecutive observational study. METHODS: Sixty-six eyes of 66 patients that underwent ICL V4c implantation were included. Pupil diameters before and 1 week, 1 month, and 3 months after surgery were measured using an automatic pupillometry system (MonCv3; Metrovision, Pérenchies, France) under four standardized illumination conditions: 0, 1, 10, and 100 cd/m2. The correlations between changes in pupil diameter and spherical equivalent values and patient age were investigated. RESULTS: Based on preoperative spherical equivalent values, included eyes were divided into a high-myopia group (-6.3 to -9.9 D (diopters)) and a super-high-myopia group (-10 to -20 D). Pupil sizes remained unchanged after surgery in the high-myopia group and decreased at 1 and 10 cd/m2 in the super-high-myopia group. A between-group comparison showed that pupils were significantly smaller in the super-high-myopia group 1 week postoperatively under all illumination conditions and remained smaller at 1 month and 3 months under 1 and 10 cd/m2 lighting conditions. Preoperative spherical equivalent values were significantly correlated with the percent decrease in pupil diameter 1 week postoperatively under 0, 1, and 10 cd/m2 illumination conditions; the greater the degree of myopia, the greater the reduction in pupil diameter. CONCLUSION: Preoperative refractive error significantly affects pupil diameter in highly myopic eyes after implantable collamer lens implantation. Pupils of super highly myopic eyes remained smaller than preoperative levels under mesopic conditions after implantable collamer lens implantation.