[Practical Application of Intelligent Vision Measurement System Based on Deep Learning].

To comprehensively assess the true visual function of clinical dry eye patients and the comprehensive impact of blinking characteristics on functional vision of the human eye, an intelligent vision measurement system has been designed and developed to detect and analyze blinks from the side. The system employs deep learning keypoint recognition technology to analyze eyelid features from a lateral perspective. It presents the data of identified key points for the upper and lower eyelids in a line chart format and annotates the trough of each blink. By setting benchmark values, the system automatically calculates the proportion of complete and incomplete blinks in the tested individuals. The results indicate that the system is stable in performance and accurate in measurement, successfully achieving the anticipated design objectives. It thereby provides reliable technical support for future clinical applications.

A rare missense PAX6 mutation causes atypical aniridia in a three-generation Chinese family.

AIM: To investigate the molecular diagnosis of a three-generation Chinese family affected with aniridia, and further to identify clinically a PAX6 missense mutation in members with atypical aniridia. METHODS: Eleven family members with and without atypical aniridia were recruited. All family members underwent comprehensive ophthalmic examinations. A combination of whole exome sequencing (WES) and direct Sanger sequencing were performed to uncover the causative mutation. RESULTS: Among the 11 family members, 8 were clinically diagnosed with congenital aniridia (atypical aniridia phenotype). A rare heterozygous mutation c.622C>T (p.Arg208Trp) in exon 8 of PAX6 was identified in all affected family members but not in the unaffected members or in healthy control subjects. CONCLUSION: A rare missense mutation in the PAX6 gene is found in members of a three-generation Chinese family with congenital atypical aniridia. This result contributes to an increase in the phenotypic spectrum caused by PAX6 missense heterozygous variants and provides useful information for the clinical diagnosis of atypical aniridia, which may also contribute to genetic counselling and family planning.

Preliminary Application of a Continuous Functional Contrast Visual Acuity System in the Assessment of Visual Function in Dry Eye Patients.

Purpose: To investigate the feasibility and efficacy of a continuous functional contrast visual acuity (CFCVA) system in the assessment of visual function in dry eye disease (DED). Methods: Twenty patients with DED and 15 normal controls were recruited. Subjective symptoms were evaluated using the Ocular Surface Disease Index (OSDI) questionnaire, and tear film stability was assessed by a noninvasive corneal topographer. Under natural blinking conditions, the custom-built CFCVA system was used to take serial visual acuity measurements at 100%, 25%, 10%, and 5% contrast for 60 seconds. A 5-minute measurement at a 100% contrast level was defined as the stress test (ST). Mean CFCVA was defined, and visual maintenance ratio (VMR) was the ratio of mean CFCVA divided by baseline visual acuity. Results: In both groups, VMR decreased and mean CFCVA (logarithm of the minimum angle of resolution) increased with decreasing optotype contrast (from 100% to 5%). In ST, the ST VMR at the fourth and fifth minutes (VMR54 and VMR55) showed the strongest correlations with OSDI total, ocular symptoms, and vision-related function (-0.646 and -0.598, -0.688 and -0.693, and -0.599 and -0.555, respectively, P < 0.05). VMR54 and VMR55 also demonstrated the best discriminating ability for detecting DED, with areas under the curve of 0.903 and 0.867, respectively. Conclusions: Extending the continuous measuring time was more effective for detecting vision-related functional abnormalities in patients with DED than simply decreasing the optotype contrast level. Translational Relevance: The proposed CFCVA system and associated parameters offer a potential method for quantifying and interpreting the visual symptoms of DED in clinical care.

Expanded phenotypic spectrum of FOXL2 Variant c.672_701dup revealed by whole-exome sequencing in a rare blepharophimosis, ptosis, and epicanthus inversus syndrome family.

INTRODUCTION: Blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES) is a rare genetic disease with diverse ocular malformations. This study aimed to investigate the disease-causing gene in members of a BPES pedigree presenting with the rare features of anisometropia, unilateral pathologic myopia (PM), and congenital cataracts. METHODS: The related BPES patients underwent a comprehensive ocular examination. Next, whole-exome sequencing (WES) was performed to screen for the disease-causing genetic variants. A step-wise variant filtering was performed to select candidate variants combined with the annotation of the variant's pathogenicity, which was assessed using several bioinformatic approaches. Co-segregation analysis and Sanger sequencing were then conducted to validate the candidate variant. RESULTS: The variant c.672_701dup in FOXL2 was identified to be the disease-causing variant in this rare BPES family. Combined with clinical manifestations, the two affected individuals were diagnosed with type II BPES. CONCLUSION: This study uncovered the variant c.672_701dup in FOXL2 as a disease causal variant in a rare-presenting BPES family with anisometropia, unilateral pathogenic myopia, and/or congenital cataracts, thus expanding the phenotypic spectrum of FOXL2.

Safety and efficacy of cataract surgery performed with a low-energy femtosecond laser compared with conventional phacoemulsification in Chinese patients: a randomized clinical trial.

BACKGROUND: To compare the safety and efficacy of femtosecond laser-assisted cataract surgery (FLACS) performed with the low-energy FEMTO LDV Z8 (Ziemer Ophthalmic Systems AG, Port, Switzerland) laser compared with conventional phacoemulsification (CP) in Chinese patients. METHODS: This prospective, multicenter, interventional study included 126 patients who were randomized (1:1) to undergo either FLACS or CP followed by intraocular lens (IOL) implantation between January 2019 and April 2020. The primary endpoint included the comparison of the endothelial cell loss (ECL) between the two groups at 3 months. Secondary endpoints included the comparison of cumulative dissipated energy (CDE), change in central corneal thickness (CCT) from baseline, and postoperative uncorrected and corrected distance visual acuities (UDVA and CDVA) in the two groups. RESULTS: At all postoperative time points, the FLACS group was found to be non-inferior to CP for the mean ECL (- 409.3 versus - 436.9 cells/mm2 at 3 months) and mean CDE (4.1 versus 4.5 percent-seconds). The increase in CCT was significantly lower in the FLACS group compared with the CP group at Day 7 (4.9 versus 9.2 µm; P = 0.04); however, the difference was not statistically significant at 1 and 3 months. Postoperatively, mean UDVA and CDVA were comparable between the two groups. No intraoperative complications occurred. CONCLUSIONS: Cataract surgery performed with a low-energy femtosecond laser was non-inferior to CP; however, the FLACS group had a statistically significantly lower increase in CCT at Day 7 compared with CP. Trial registration This trial is registered at ClinicalTrials.gov on May 15, 2019, with trial registration number: NCT03953053.

Simultaneous real-time analysis of tear film optical quality dynamics and functional visual acuity in dry eye disease.

BACKGROUND: To assess the effect of tear film instability in dry eye disease (DED) by measuring visual performance and tear film optical quality in a simultaneous real-time analysis system. METHODS: Thirty-seven DED participants and 20 normal controls were recruited. A simultaneous real-time analysis system was developed by adding a functional visual acuity (FVA) channel to a double-pass system. Repeated measurements of FVA and objective scatter index (OSI) were performed simultaneously with this system under blink suppression condition for 20 s. Patient-reported symptoms was evaluated using the Ocular Surface Disease Index (OSDI) questionnaire. Mean FVA, mean OSI, and visual acuity break-up time were defined. The OSI maintenance ratio was calculated as an evaluation index to assess the difference between dynamic OSI changes and baseline OSI. The visual maintenance ratio was also calculated in the same way. RESULTS: Moderate correlations were noted between mean OSI and FVA-related parameters (mean FVA, visual maintenance ratio, visual acuity break-up time: 0.53, - 0.56, - 0.53, respectively, P < 0.01 for all). Moderate to high correlations were noted between OSI maintenance ratio and FVA-related parameters (mean FVA, visual maintenance ratio, visual acuity break-up time: - 0.62, 0.71, 0.64, respectively, all P < 0.01). The metrics derived from the simultaneous real-time analysis system were moderately correlated with the patient-reported symptoms and the visual acuity break-up time possessed the highest correlation coefficients with OSDI total, ocular symptoms, and vision-related function (- 0.64, - 0.63, - 0.62, respectively, P < 0.01). The OSI-maintenance ratio alone appeared to exhibit the best performance of the metrics for the detection of DED with sensitivity of 95.0% and specificity of 83.8% and the combinations of FVA parameters and OSI parameters were valid and can further improve the discriminating abilities. CONCLUSIONS: OSI-related metrics were found to be potential indicators for assessing and diagnosing DED which correlated with both subjective visual performance and patient-reported symptoms; the FVA-related metrics were quantifiable indicators for evaluating visual acuity decline in DED. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry, ChiCTR2100051650. Registered 29 September 2021, https://www.chictr.org.cn/showproj.aspx?proj=134612.

Posterior scleral contraction to treat myopic traction maculopathy at different stages.

OBJECTIVE: We aimed to evaluate anatomical and functional outcomes and determine posterior scleral contraction (PSC) timing in treating myopic traction maculopathy (MTM). METHODS: This is a retrospective study of MTM patients undergoing PSC with genipin cross-linked strip at a single hospital site. Differences in demographic and clinical characteristics were compared among three groups defined by the MTM staging system. All patients were followed up for at least one year postoperatively. The best-corrected visual acuity (BCVA), macular hole diameter, axial length (AL), optical coherence tomography findings, and the complications were evaluated. Additionally, regression analyses were performed to account for confounders. RESULTS: Sixty-one MTM patients (24 eyes at stage 2, 22 eyes at stage 3, and 18 eyes at stage 4) were included. The macular holes were closed in 16 eyes (66.7%), 13 eyes (59.0%), and 11 eyes (61.1%) at stage 2, stage 3, and stage 4, respectively. PSC improved the BCVA in patients at each stage (all P < 0.05). Postoperative BCVA at stage 2 was significantly better than that at stage 4 (P = 0.0069). Preoperative BCVA was associated with postoperative BCVA (P < 0.001). Preoperative AL (OR 0.676, 95% CI 0.480 to 0.951, P = 0.025), AL shortening amount (OR 5.129, 95% CI 1.974 to 13.327, P = 0.001) and macular hole diameter (OR 1.003, 95% CI 1.000 to 1.006, P = 0.030) were associated with macular hole closure. CONCLUSIONS: PSC is safe and effective in treating MTM at different stages. Early PSC intervention will have more significant visual benefits.

Clinical Accuracy of 6 Intraocular Lens Power Calculation Formulas in Elongated Eyes, According to Anterior Chamber Depth.

PURPOSE: To investigate the influence of anterior chamber depth (ACD) on the accuracy of the Kane, EVO 2.0, Barrett Universal II (BU II), Olsen, SRK/T, and Haigis formulas in patients with elongated eyes. DESIGN: Retrospective case series study. METHODS: A total of 106 patients (106 eyes) diagnosed with high myopia (axial length ≥26 mm) were enrolled and divided into 3 subgroups according to preoperative ACD. Mean refractive error (ME), mean absolute refractive error (MAE), median absolute refractive error (MedAE), and proportions of eyes within ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D were calculated. RESULTS: In all patients, the MedAE was lowest for the Kane formula (0.28 D), followed by the BU II (0.34 D). In the shallow ACD subgroup, EVO 2.0 formula produced the lowest MedAE (0.22 D), and the highest proportion of eyes within ±0.25 D (58%); the BU II (0.23 D, 50%) and Kane (0.25 D, 50%) formulas produced similar proportions. In the deep ACD group, the MedAEs of the Haigis and SRK/T formulas (0.68 D and 0.50 D, respectively) were significantly higher than those of the EVO 2.0 (0.37 D), Kane (0.30 D), BU II (0.43 D), and Olsen (0.34 D) formulas (P < 0.05). CONCLUSIONS: Overall, the Kane and EVO 2.0 formulas had the highest accuracy. EVO 2.0 and BU II formulas are recommended for patients with shallow ACD; the Kane formula is recommended for patients with deep ACD (especially patients with extremely elongated eyes). The SRK/T and Haigis formulas should be avoided as much as possible.

POSTERIOR SCLERAL CONTRACTION TO TREAT MYOPIC FOVEOSCHISIS IN HIGHLY MYOPIC EYES.

PURPOSE: To evaluate the efficacy of posterior scleral contraction to treat myopic foveoschisis (MF). METHODS: The records of MF patients treated with posterior scleral contraction were reviewed. During posterior scleral contraction, a cross-linked fusiform strip from allogeneic sclera was used and designed axial length (AL) shortening amount was around 2.0∼3.0 mm based on preoperative AL. The middle part of the strip was placed at the posterior pole of the eye. After few aqueous humors were released, the strip was tightened to contract posterior sclera and shorten AL. Clinical data were collected at pre-operation (op) and post-op follow-ups for 12 months. RESULTS: Twenty-four eyes were collected. The AL at pre-op, post-op 1-week, 3-month, 6-month, and 12-month were 29.84 ± 1.24, 27.39 ± 1.32, 27.73 ± 1.23, 27.86 ± 1.26, and 27.91 ± 1.29 mm. There was no AL difference between post-op 6-month and 12-month (P = 0.242). The accumulated MF reattachment rate at post-op 1-week, 3-month, 6-month, and 12-month were 8.3%, 16.7%, 50.5%, and 95.8%. The best-corrected visual acuity at post-op 6-month and 12-month were 0.71 ± 0.39 (Snellen acuity 20/80) and 0.64 ± 0.37 (Snellen acuity 20/63), improving significantly compared with pre-op (P = 0.006 and <0.001). CONCLUSION: The posterior scleral contraction was effective to treat MF. The AL stabilized after post-op 6-month and MF reattached gradually with improved visual acuity up to post-op 12-month.

Corneal biomechanical properties in myopic eyes evaluated via Scheimpflug imaging.

BACKGROUND: To investigate the biomechanical properties of the cornea in myopic eyes using corneal visualization Scheimpflug technology (Corvis ST). The relationships between the biomechanical properties of the cornea and the degree of myopia were also investigated. METHODS: 265 eyes of 265 subjects were included. Based on spherical equivalent (SE) in diopters (D), participants were divided into four groups: low myopia/control (SE: - 0.50 to - 3.00D), moderate myopia (SE: - 3.00 to - 6.00D), high myopia (SE: - 6.00 to - 10.00D) and severe myopia (SE greater than - 10.00D). Axial length (AL), anterior segment parameters, and corneal biomechanical properties were obtained with the Lenstar LS900, Pentacam HR and Corvis ST, respectively. RESULTS: Mean (±SD) SE was - 7.29 ± 4.31D (range: - 0.63 to - 25.75D). Mean AL was 26.31 ± 1.82 mm (range: 21.87 to 31.94 mm). Significant differences were detected within the four groups in terms of six corneal biomechanical parameters: deformation amplitude (DA), time from start until second applanation (A2-time), length of flattened cornea at the second applanation (A2-length), corneal velocity during the first and second applanation (A2-velocity), time from start to highest concavity (HC-time), and central curvature at highest concavity (HC radius). AL was positively associated with DA whereas negatively associated with A1-velocity and A2-length. SE was positively associated with A2-time, HC-time and A2-velocity, whereas negatively associated with DA. IOP was positively associated with four corneal biomechanical parameters and negatively associated with three parameters. CONCLUSIONS: Eyes with severe myopia showed greater DA, lesser A2 time, HC time, and faster A2-velocity compared to low to high myopia. This suggests the cornea becomes weaker and more deformable with elongation of axial length with corresponding increases in myopia. DA, A2-time and A2-velocity could be useful corneal biomechanical indicators in patients with myopia.

A novel ophthalmic viscosurgical device-free phakic intraocular lens implantation makes myopic surgery safer.

PURPOSE: To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free (OVD-free) method for posterior chamber phakic intraocular lens (PIOL) implantation in myopic eyes. METHODS: In this retrospective cohort study, the medical records of myopic eyes that underwent PIOL (Implantable Collamer Lens, ICL) implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed. A total of 49 eyes with complete data that met follow up requirements (2 h, 1 day, 1 week, 3 months postoperatively) were recruited. Based on the surgical techniques used, the eyes were divided into the OVD-free method group and the standard method group. The clinical data, including intraocular pressure (IOP), corrected distance visual acuity (CDVA) and spherical equivalent (SE), at each follow-up were collected for comparison. Endothelial cell loss and complications were also investigated. RESULTS: Twenty-one eyes received the standard method, and 28 eyes received the OVD-free method. A rise in IOP > 22 mmHg at 2 h was noted in 14 eyes (66.7%) in the standard group and none (0%) in the OVD-free group (p < 0.001). The rise in IOP from baseline was significantly higher at 2 h in the standard group (10.5 ± 5.2 mmHg vs. 2.2 ± 3.3 mmHg, difference: 8.3, 95% CI 5.8 to 10.8; p < 0.001). There was a significant difference in the time course of LogMAR CDVA changes between the two groups (p = 0.047). The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day (- 0.076, 95% CI - 0.134 to - 0.018; p = 0.012), 1 week (- 0.071, 95% CI - 0.135 to - 0.007; p = 0.03), but not at 3 months (- 0.046, 95% CI - 0.107 to 0.015; p = 0.134). There was no significant difference in the time course of SE changes between the two groups (p = 0.471; p = 0.705). In the OVD-free group, mean endothelial cell loss was 4.6% at 3 months (2522 ± 281 vs. 2407 ± 226 cells/mm2, difference: -115, 95% CI - 295 to 65; p = 0.187). No complications were reported in both groups except for the early IOP elevation in the standard group during the observation period. CONCLUSIONS: The OVD-free method is safe and efficient for ICL implantation. It can be a safer method of ICL implantation compared to the standard method in that it completely eliminates ophthalmic viscoelastic devices-related complications without causing additional complications.

A comprehensive Chinese experience against SARS-CoV-2 in ophthalmology.

The 2019 novel coronavirus disease (COVID-19) has now swept through the continents and poses a global threat to public health. Several investigations have been conducted to identify whether COVID-19 can be transmitted through the ocular route, and the conclusion is that it is a potential route but remains uncertain. Due to the face-to-face communication with patients, frequent exposure to tears and ocular discharge, and the unavoidable use of equipment which requires close proximity, ophthalmologists carry a high risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Based on 33 articles published by Chinese scholars, guidelines and clinical practice experience in domestic hospitals, we have summarized the Chinese experience through the lens of ophthalmology, hoping to make a contribution to protecting ophthalmologists and patients around the world.

POSTERIOR SCLERAL CONTRACTION TO TREAT RECURRENT OR PERSISTENT MACULAR DETACHMENT AFTER PREVIOUS VITRECTOMY IN HIGHLY MYOPIC EYES.

PURPOSE: To determine the efficacy of posterior scleral contraction (PSC) to treat recurrent or persistent macular detachment after previous vitrectomy in highly myopic eyes. METHODS: We reviewed the medical records of patients with high myopia and recurrent or persistent macular detachment after previous vitrectomy treated with PSC at our hospital between April 2013 and March 2017. Fourteen eyes (14 patients; mean age, 58.93 ± 11.08 years) were included. Sclera cross-linked with genipin was used for PSC. The desired axial length decrease was 0.1-fold. The reattachment rate, best-corrected visual acuity, and axial length changes were evaluated. RESULTS: The macular reattachment rate was 100%. In seven eyes with a silicone oil tamponade, the oil was successfully removed 2 weeks to 4 months after surgery. The best-corrected visual acuity improved significantly postoperatively (Snellen acuity improved from 20/1,000-20/400) (1.75 ± 0.90 vs. 1.34 ± 0.58 logarithm of the minimal angle of resolution; P < 0.05). Eight eyes (57.14%) improved; six eyes (43.86%) remained stable. The axial length decreased significantly postoperatively (31.32 ± 3.04 vs. 29.08 ± 3.05 mm; P < 0.05). CONCLUSION: Posterior scleral contraction is safe and effective for recurrent and persistent macular detachment after previous vitrectomy in highly myopic eyes. The silicone oil is removed after PSC, and vision can be preserved in these refractory cases.

Changes and Diurnal Variation of Visual Quality after Orthokeratology in Myopic Children.

PURPOSE: To assess the changes and the diurnal variation of visual quality after orthokeratology in myopic children. METHODS: Forty-four eyes of 22 subjects with a mean age of 10.55 ± 1.53 years (8 to 14 years) were enrolled in this prospective study. Their spherical equivalent ranged from -1.25 to -4.25 diopters (D) and astigmatism was less than 1.00 D. Parameters including corneal curvature, ocular objective scatter index (OSI), the modulation transfer function (MTF), root mean square of ocular and corneal wavefront aberrations, and contrast sensitivity function (CSF) were measured before and at two time points during the same day after 1 month of orthokeratology. RESULTS: After orthokeratology, uncorrected visual acuity (UCVA) and spherical equivalent were significantly improved from baseline (P < 0.001), and their diurnal variation was not significant (P=0.083, 0.568). OSI increased from 0.29 ± 0.15 to 0.65 ± 0.31 (P < 0.001). MTF decreased significantly (P < 0.01). Corneal curvature and ocular total aberration decreased (P < 0.001), while the ocular and corneal higher-order aberration increased significantly (P < 0.01). The CSF under photopic condition decreased at 3 cpd (P=0.006) and increased at 18 cpd (P=0.012). The diurnal variation of CSF at 18 cpd under mesopic and high glare conditions and at 12 cpd under photopic condition was significant (P=0.002, 0.01, 0.017). CONCLUSIONS: Orthokeratology can effectively improve UCVA and high spatial frequency CSF by decreasing the low-order aberrations. However, MTF and CSF at low spatial frequency decreased because of the increase of intraocular scattering and high-order aberrations. Meanwhile, CSF at high spatial frequency fluctuates significantly at two times during the same day after 1 month orthokeratology.

Age-Related Changes in Corneal Spherical Aberration.

PURPOSE: To analyze the age-related changes in corneal spherical aberration (CSA) and higher order aberrations (HOAs) and to develop a novel model to estimate the change in CSA with age. METHODS: This was a cross-sectional study of the right eyes of 3,769 patients. Anterior corneal spherical aberration (ASA), posterior corneal spherical aberration (PSA), total corneal spherical aberration (TSA), and the root mean square of corneal HOAs were measured using a Scheimpflug tomographer. Smoothed fitting curves were plotted as a function of age and the average change in spherical aberration was calculated for different ages. RESULTS: The mean magnitude of ASA, PSA, TSA, and HOAs (6 and 4 mm) were 0.270 ± 0.111, -0.144 ± 0.031, 0.228 ± 0.120, 0.453 ± 0.194, and 0.141 ± 0.075 µm, respectively. All parameters showed a statistically significant non-linear change with age. The age after which the aberrations increased at a faster rate, namely the turning points of age, were 39 years for ASA, PSA, TSA, and 6-mm HOAs (95% confidence interval [CI]: 35 to 42, 36 to 41, 36 to 42, and 35 to 56 years, respectively) and 46 years for 4-mm HOAs (95% CI: 36 to 56 years). There were significant increases in increment rates after the turning points. The average change of TSA was -0.013 µm/10 years from 18 to 39 years and 0.057 µm/10 years after 39 years. There were statistically significant correlations between ASA and TSA (r = 0.976, P < .001) and PSA and TSA (r = 0.192, P < .001), but not between ASA and PSA (r = -0.003, P = .835). CONCLUSIONS: CSA and HOAs increased non-linearly with age and became more positive after 39 and 46 years of age, respectively. Based on the increment rates and turning points of age, a novel model is provided to help calculate the value required to compensate for the increasing CSA associated with the aging cornea. [J Refract Surg. 2018;34(11):760-767.].

Posterior scleral reinforcement using genipin-cross-linked sclera for macular hole retinal detachment in highly myopic eyes.

BACKGROUND/AIMS: To investigate the surgical outcomes of posterior scleral reinforcement (PSR) using genipin-cross-linked sclera to treat macular hole retinal detachment (MHRD) in highly myopic eyes. METHODS: Nineteen patients with high myopia (19 eyes) with MHRD were treated sequentially with genipin-cross-linked PSR and were followed at least for 1 year after the surgery. The best corrected visual acuity (BCVA), axial length (AL), optical coherence tomography (OCT) outcomes and the complications were evaluated. RESULTS: Macular hole was closed in 73.7% of the eyes, foveal reattachment rate was 100%. The mean logMAR BCVA improved from 1.27±0.55 preoperatively to 0.88±0.55 postoperatively. The preoperative AL (29.88±1.97 mm) was decreased (27.73±1.84 mm) after the operation (p<0.001). CONCLUSIONS: For at least a 1-year period of follow-up, PSR with genipin-cross-linked sclera should be considered as a preferred surgical approach to treat MHRD in highly myopic eyes, especially when foveal retinoschisis is also documented.

The efficacy of posterior scleral contraction in controlling high myopia in young people.

OBJECTIVE: To investigate the clinical effectiveness and safety of posterior scleral contraction (PSC) surgery in controlling high myopia in young people. METHODS: Twenty patients with high myopia (30 eyes) were treated with PSC. The average age for the patients was 11.45 ± 5.17 years old (range 3-22). A genipin cross-linked sclera was implanted to the posterior sclera in PSC surgery. Axial length and myopia progression rates were measured at least two years before and after PSC surgery. RESULTS: Prior to surgery, the mean AL progression was 0.73 ± 0.33 mm, compared to -0.08 ± 0.31 mm (P=0.00) post-surgery; the degree of myopia increased was -1.40 ± 0.95 D, compared to 0.18 ± 1.10 D post-surgery (P=0.00). The best corrected visual acuity (BCVA, in LogMAR) improved from 0.21 ± 0.16 preoperatively to 0.13 ± 0.13 two years after PSC (P=0.014). CONCLUSIONS: PSC can restrict AL extension and safely control high myopia progression in young people.

Age-Related Changes in Corneal Astigmatism.

PURPOSE: To analyze the changes in corneal astigmatism as a function of age and develop a novel model to estimate corneal astigmatic change according to age. METHODS: This was a cross-sectional study of right eyes of 3,769 individuals. Total corneal astigmatism, keratometric astigmatism, anterior corneal astigmatism, and posterior corneal astigmatism were measured by a Scheimpflug tomographer. Smoothing fitting curves of polar values of corneal astigmatism as a function of age were drawn and average changes in corneal astigmatism at different ages were calculated. RESULTS: Two turning points of age on total corneal astigmatism were 36 and 69 years. The average change of total corneal astigmatism toward against-the-rule astigmatism was 0.13 diopters (D)/10 years from 18 to 35 years, 0.45 D/10 years from 36 to 68 years, and decreased after 69 years, mainly caused by anterior corneal astigmatism. The mean magnitude of posterior corneal astigmatism was -0.33 D and exceeded 0.50 D in 14.27% of eyes. The vectorial difference between total corneal astigmatism and keratometric astigmatism was correlated with posterior corneal astigmatism, polar value of anterior corneal astigmatism, age, and corneal higher order aberrations (r = 0.636; standard partial regression coefficients were 0.479, -0.466, 0.282, and 0.196, respectively; all P < .001). Based on the non-linear model to estimate corneal astigmatic change with age, a formula was developed to calculate recommended correction of astigmatism according to age and astigmatic type. CONCLUSIONS: The rate of change of total corneal astigmatism showed a non-linear trend toward against-the-rule astigmatism, which was low at young and old age, high at middle age, and should be taken into account when performing surgery to correct astigmatism. [J Refract Surg. 2017;33(10):696-703.].

Investigation of a real-time location system of corneal astigmatic axis.

BACKGROUND: To construct a real-time computerized location system (RCLS) to analyze and display the axis of corneal astigmatism and to compare its accuracy with the Scheimpflug method. METHODS: Fifty-seven eyes of 39 volunteers with corneal astigmatism more than 1.00 diopter (D) were recruited. The RCLS was composed of a circular light-emitting diode (LED) light source, surgical microscope, surgical video system, computer and self-programming image analysis software. Scheimpflug imaging measurements (Pentacam HR, Oculus, Wetzlar, Germany) were performed on all subjects to determine the axis and power of corneal astigmatism. Thereafter, the axis of corneal astigmatism was analyzed in real-time and displayed by the RCLS on supine position, and videos were recorded. The MB-Ruler 4.0 software was used to measure the astigmatic axis. The accuracy of the RCLS was compared with the Scheimpflug method. RESULTS: The RCLS was able to display the axis of corneal astigmatism in real-time. The axial deviation of corneal astigmatism between the two methods was 0.63 ± 3.78° when astigmatism was 1.00 to 2.00 D and decreased to 0.06 ± 1.38° when astigmatism was greater than 2.00 D. A linear correlation of astigmatic axis was noted between the two methods: AxisRCLS = 1.01 × AxisScheimpflug - 1.02 (R2 = 0.998, P < 0.001). The Bland-Altman analysis revealed that the RCLS agreed sufficiently well with the Scheimpflug method. CONCLUSIONS: The RCLS can accurately analyze and display the axis for corneal astigmatism greater than 1.00 D in real-time. The RCLS simplifies marking procedures and may have potential clinical application to improve the postoperative visual outcomes in surgical correction of corneal astigmatism.

Clinical Investigation of the Posterior scleral contraction to Treat Macular Traction Maculopathy in Highly Myopic Eyes.

Myopic traction maculopathy (MTM) can cause vision disabilities in highly myopic eyes. This retrospective case series investigated the clinical outcomes of posterior scleral contraction (PSC) using genipin-cross-linked sclera as the material to treat MTM in highly myopic eyes. In total, 32 eyes from 29 highly myopic patients who underwent PSC for MTM were recruited. The changes in best-corrected visual acuity (BCVA) and axial length were evaluated, macular reattachment and macular hole (MH) closure was assessed by optical coherence tomography, and complications were evaluated. At the final follow-up, the retina was completely reattached in 25 eyes (78.1%), essentially reattached in 4 eyes (12.5%), and partially reattached in 3 eyes (9.4%). The logMAR BCVA improved significantly from 1.18 ± 0.45 preoperatively to 0.87 ± 0.45 postoperatively (P < 0.001). The 32 eyes were further divided into the MH group (16 eyes) and the non-MH group (16 eyes) for comparison. The MH was closed in 9 eyes (56.3%). The retinal reattachment rate was 75.0% in the MH group and 81.25% in the non-MH group, and the logMAR BCVA improved significantly in both groups. The PSC using genipin-cross-linked sclera as the material can effectively treat MTM in highly myopic eyes, and significant visual improvement can be achieved with minimal complications.