Treatment Of Myopia Research Articles

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.

Applications of Artificial Intelligence in Myopia: Current and Future Directions.

With the continuous development of computer technology, big data acquisition and imaging methods, the application of artificial intelligence (AI) in medical fields is expanding. The use of machine learning and deep learning in the diagnosis and treatment of ophthalmic diseases is becoming more widespread. As one of the main causes of visual impairment, myopia has a high global prevalence. Early screening or diagnosis of myopia, combined with other effective therapeutic interventions, is very important to maintain a patient's visual function and quality of life. Through the training of fundus photography, optical coherence tomography, and slit lamp images and through platforms provided by telemedicine, AI shows great application potential in the detection, diagnosis, progression prediction and treatment of myopia. In addition, AI models and wearable devices based on other forms of data also perform well in the behavioral intervention of myopia patients. Admittedly, there are still some challenges in the practical application of AI in myopia, such as the standardization of datasets; acceptance attitudes of users; and ethical, legal and regulatory issues. This paper reviews the clinical application status, potential challenges and future directions of AI in myopia and proposes that the establishment of an AI-integrated telemedicine platform will be a new direction for myopia management in the post-COVID-19 period.

Efficacy and safety of traditional Chinese medicine decoction in the treatment of adolescent myopia: A protocol for systematic review and network meta-analysis.

Background:Adolescent myopia has become a major public health problem in Asian countries and even the world. Due to its unstable prognosis and numerous complications, it has caused serious social and economic burden. As a common treatment in Asia, Chinese medicine has been shown to be effective in controlling the development of myopia, but its evidence-based medical evidence is not sufficient. Therefore, the purpose of this study is to evaluate the efficacy and safety of traditional Chinese medicine (TCM) in the treatment of adolescent myopia through network meta-analysis, and to provide evidence for clinical and scientific research.Methods:We searched seven databases for randomized controlled trials of TCM decoction for adolescent myopia, including PubMed, the Cochrane Library, EMbase, China National Knowledge Infrastructure, China Biological Medicine, Chinese Scientific Journals Database, and wan-fang databases, from the date of the establishment of each database to January 31, 2022. The network meta-analysis will be implemented through Aggregate Data Drug Information System 1.16.8 and Stata 13.0 software. Primary outcomes include distant vision, intraocular pressure, and diopter. Mean differences or odds ratios will be used for statistical analysis. We will ensure the reliability of the results through node-split model and heterogeneity analysis. In addition, the Cochrane Collaboration's tool and Grading of Recommendations Assessment, Development and Evaluation system will be used for the methodological quality and the evidence quality.Results:This study will provide reliable evidence for the clinical selection of TCM decoction in the treatment of adolescent myopia.Conclusion:The results of this study will evaluate the efficacy and safety of TCM decoction in the treatment of adolescent myopia, and provide decision-making references for future clinical and scientific research.Ethics and dissemination:This study did not require ethical approval. We will disseminate our findings by publishing results in a peer-reviewed journal.OSF registration number:DOI 10.17605/OSF.IO/VXQUP.

Efficacy of mitomycin C 0.02% for prevention of haze after transepithelial photorefractive keratectomy for mild and moderate myopia

Objective: To investigate the efficacy of mitomycin C (MMC) 0.02% for prevention of haze after transepithelial photorefractive keratectomy (Trans-PRK) for mild and moderate myopia. Methods: Retrospective cohort study. We reviewed medical records of 295 patients (588 eyes) who underwent Trans-PRK with or without use of MMC. There were 45 patients (90 eyes) in the mild myopia group (aged between 18 and 41 years; 37 males and 8 females; myopia diopter <3.00 D) and 250 patients (498 eyes) in the moderate myopia group (aged between 18 and 46 years; 168 males and 82 females; myopia diopter: 3.00 to 6.00 D). The two groups were divided into subgroups with MMC 0.02% and without MMC, respectively. The time of intraoperative application of MMC, if there was, was 15 s and 30 s in the mild myopia group and the moderate myopia group, respectively. The mean follow-up time was 6 months. Postoperative best corrected visual acuity (BCVA), spherical equivalent (SE) and haze were analyzed and compared using an independent Student t-test or Mann-Whitney U test between subgroups. Haze variables were compared using chi-square statistics. Results: Haze was quantified with Fantes from grade 0.5 to 4. In the mild myopia group, all haze grades were 0.5 within 3 months. The incidence of haze was 6.25% (2/32) in eyes treated with MMC and 8.62% (5/58) in eyes treated without MMC; there was no statistical significance (χ²=0.00, P>0.999). In the moderate myopia group, the incidence of haze was 9.19% (24/261) in eyes treated with MMC within 3 months; the grade was 0.5 in 91.67% (22/24) of eyes with haze and 1 in 8.33% (2/24). The incidence of haze was 29.53% (70/237) in eyes treated without MMC; the grade was 0.5 in 60.00% (42/70) of eyes with haze, 1 in 18.57% (13/70), and 2 in 5.71% (4/70) within 3 months, and 0.5 in 15.71% (11/70) after 3 months (χ²=12.36, P=0.002). In the mild myopia group, BCVA was 5.0(5.0, 5.1) versus 5.0(5.0, 5.1) in the subgroups with MMC and without MMC (Z=-0.34, P=0.733). In the moderate myopia group, BCVA was 5.0(5.0, 5.1) versus 5.0(5.0, 5.1) in the subgroups with and without MMC (Z=-2.05, P=0.040). In the mild myopia group, SE was (0.33±1.07) D versus (0.32±0.57) D in the subgroups with and without MMC (t=0.25, P=0.805). In the moderate myopia group, SE was (0.66±0.85) D versus (0.53±0.67) D in the subgroups with and without MMC (t=2.97, P=0.003). Conclusions: MMC 0.02% was effective in preventing haze after Trans-PRK in the treatment of moderate myopia. However, it was not effective in mild myopia.

Efficacy and safety of acupuncture for patients with pseudomyopia: A protocol for systematic review and meta-analysis.

Background:Myopia are common health problems that people experience in daily life. Pediatric myopia has become a major international public health concern that has a negative impact on physical, mental health of patients, and quality of life. Currently, there is no cure available. Press needle as an adjuvant therapy is currently undergoing clinical trials in different medical centers. However, no relevant systematic review or meta-analysis has been designed to evaluate the effects of press needle patching on early myopia. There is also a lack of systematic evaluation and analysis of acupoints and thumbtack needle.Methods:We will electronically search Medline, Embase, PubMed, Web of Science, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Scientific Journal Database, and Wan-Fang Database from their inception to October 2021. In addition, we will manually retrieve other resources including the reference lists of identified publications, conference articles, and gray literature. The clinical randomized controlled trials or quasi-randomized controlled trials related to press needle for the treatment of early myopia will be included in the study. The language is limited to Chinese and English. Research selection, data extraction, and research quality assessment will be independently completed by 2 researchers. Data were synthesized by using afixed effect model or random effect model depend on the heterogeneity test. The total effective rate was the primary outcomes. RevMan V.5.3 statistical software will be used for meta-analysis. If it is not appropriate for a meta-analysis, then a descriptive analysis will be conducted. Data synthesis will use the risk ratio and the standardized or weighted average difference of continuous data to represent the results.Results:This study will analyze the clinical effective rate, pesudomyopia outcomes, quality of life, improvement of clinical symptoms of pesudomyopia, and validity of thumbtack needle for patients with pesudomyopia.Conclusion:This systematic review will provide evidence to judge whether thumbtack needle is an effective intervention for patients with early myopia.Systematic review registration:PROSPERO, CRD42021243151.

Alteration of EIF2 Signaling, Glycolysis, and Dopamine Secretion in Form-Deprived Myopia in Response to 1% Atropine Treatment: Evidence From Interactive iTRAQ-MS and SWATH-MS Proteomics Using a Guinea Pig Model.

Purpose: Atropine, a non-selective muscarinic antagonist, effectively slows down myopia progression in human adolescents and several animal models. However, the underlying molecular mechanism is unclear. The current study investigated retinal protein changes of form-deprived myopic (FDM) guinea pigs in response to topical administration of 1% atropine gel (10 g/L). Methods: At the first stage, the differentially expressed proteins were screened using fractionated isobaric tags for a relative and absolute quantification (iTRAQ) approach, coupled with nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS) (n = 24, 48 eyes) using a sample pooling technique. At the second stage, retinal tissues from another cohort with the same treatment (n = 12, 24 eyes) with significant ocular changes were subjected to label-free sequential window acquisition of all theoretical mass spectra (SWATH-MS) proteomics for orthogonal protein target confirmation. The localization of Alpha-synuclein was verified using immunohistochemistry and confocal imaging. Results: A total of 1,695 proteins (8,875 peptides) were identified with 479 regulated proteins (FC ≥ 1.5 or ≤0.67) found from FDM eyes and atropine-treated eyes receiving 4-weeks drug treatment using iTRAQ-MS proteomics. Combining the iTRAQ-MS and SWATH-MS datasets, a total of 29 confident proteins at 1% FDR were consistently quantified and matched, comprising 12 up-regulated and 17 down-regulated proteins which differed between FDM eyes and atropine treated eyes (iTRAQ: FC ≥ 1.5 or ≤0.67, SWATH: FC ≥ 1.4 or ≤0.71, p-value of ≤0.05). Bioinformatics analysis using IPA and STRING databases of these commonly regulated proteins revealed the involvement of the three commonly significant pathways: EIF2 signaling; glycolysis; and dopamine secretion. Additionally, the most significantly regulated proteins were closely connected to Alpha-synuclein (SNCA). Using immunostaining (n = 3), SNCA was further confirmed in the inner margin of the inner nuclear layer (INL) and spread throughout the inner plexiform layer (IPL) of the retina of guinea pigs. Conclusion: The molecular evidence using next-generation proteomics (NGP) revealed that retinal EIF2 signaling, glycolysis, and dopamine secretion through SNCA are implicated in atropine treatment of myopia in the FDM-induced guinea pig model.

Early onset X‐linked female limited high myopia in three multigenerational families caused by novel mutations in the ARR3 gene

This study describes the clinical spectrum and genetic background of high myopia caused by mutations in the ARR3 gene. We performed an observational case series of three multigenerational families with high myopia (SER≤−6D), from the departments of Clinical Genetics and Ophthalmology of a tertiary Dutch hospital. Whole‐exome sequencing (WES) with a vision‐related gene panel was performed, followed by a full open exome sequencing. We identified three Caucasian families with high myopia caused by three different pathogenic variants in the ARR3 gene (c.214C>T, p.Arg72*; c.767+1G>A; p.?; c.848delG, p.(Gly283fs)). Myopia was characterized by a high severity (<−8D), an early onset (<6 years), progressive nature, and a moderate to bad atropine treatment response. Remarkably, a female limited inheritance pattern was present in all three families accordant with previous reports. The frequency of a pathogenic variant in the ARR3 gene in our diagnostic WES cohort was 5%. To conclude, we identified three families with early onset, therapy‐resistant, high myopia with a female‐limited inheritance pattern, caused by a mutation in the ARR3 gene. The singular mode of inheritance might be explained by metabolic interference due to X‐inactivation. Identification of this type of high myopia will improve prompt myopia treatment, monitoring, and genetic counseling.

The 100 most influential articles in myopia: a bibliometric analysis.

To identify and characterize the 100 most influential articles in the field of myopia over the last decades. Articles on myopia published between January 1975 and March 2020 were searched through the Web of Science Core Collection database. Two independent authors reviewed and determined the 100 most cited articles. The characteristics of each eligible article were recorded, including authors, institutions, countries, journals, publication date, total citations (TCs), annual citations (ACs), research focus and article type. The top 100 most influential articles were published between 1983 and 2016, with 1999 as the most prolific year. The mean number of TCs was 288 (range: 193-537) and the mean number of ACs was 19 (range: 7-109). Treatment and epidemiology of myopia were the most important research focus. These articles were published in 21 journals led by Ophthalmology (29%) followed by Investigative Ophthalmology & Visual Science (23%). The number of ACs for articles published in the last ten years was significantly higher than that for the other most-cited articles (44 vs 16, Mann-Whitney U test P<0.01). There is no difference in the number of TCs between original articles and review articles, while the number of ACs for review articles was significantly higher than that for original articles (22 vs 17, Mann-Whitney U test P<0.05). This bibliometric analysis can provide us with concise information about the development trend of research in the field of myopia in the past few decades, and provide an important reference for researchers to guide future research.

Comparison of visual and refractive outcomes between femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and photorefractive keratectomy (PRK): a long-term outcomes analysis

Aim: We aimed to compare the results of photorefractive keratectomy (PRK) and femtosecond-assisted laser in situ keratomileusis (FS-LASIK) procedures in the treatment of myopia and myopic astigmatism.&#x0D; Material and Method: Seventy eyes of 35 patients with myopia and/or myopic astigmatism who had undergone PRK procedure were compared retrospectively with 70 eyes of 35 patients with myopia and/or myopic astigmatism who had undergone FS-LASIK procedure. &#x0D; Results: All patients completed the 2-year follow-up period. With respect to age and sex, PRK and FS-LASIK groups were comparable. The differences in uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and spherical equivalent were significantly better with PRK than with FS-LASIK at 6- and 24-month visits. FS-LASIK and PRK had similar values of safety index, efficacy index, and predictability at 6 and 24 months postoperatively. No significant complications were observed in neither of the procedures during the follow-up period. &#x0D; Conclusion: Both PRK and FS-LASIK seem equally effective options for the correction of myopia and myopic astigmatism. However, PRK provided slightly better visual and refractive outcomes than FS-LASIK at 6 and 24 months postoperatively.

Analysis of the Effectiveness of SMILE, FS-LASIK, and SBK in Myopic Patients and the Impact in UCVA and Tear Film Stability.

The aim of the present study was to investigate the effect of femtosecond laser small incision stromal lens extraction (SMILE), femtosecond laser-assisted excimer laser keratomileusis (FS-LASIK), and anterior elastic sublaminar laser keratomileusis (SBK) in myopic patients, and their effects on uncorrected visual acuity (UCVA) and tear film stability. 600 myopic patients admitted to our hospital from January 2020 to December 2021 were selected for the study and divided into SMILE group (200 patients, SMILE treatment), FS-LASIK group (200 patients, FS-LASIK treatment), and SBK group (200 patients, SBK treatment) according to the random number table method. Uncorrected visual acuity (UCVA), tear breakup time (BUT), tear secretion function test (Sit), and corneal higher-order image aberration global higher-order aberration (HOAS) were compared among the three groups. The UCVA values before operation, 2 weeks after operation, 1 month after operation, and 3 months after operation in the three groups were similar, and the BUT, Sit value, and HOAS of corneal higher-order image difference in the three groups were similar, and the differences were not statistically significant (P > 0.05). The BUT, Sit value, and HOAS of corneal higher-order image difference at 1 and 3 months after surgery in the SMILE group were higher than those in the FS-LASIK and SBK groups, and the differences were statistically significant (P < 0.05). SMILE, FS-LASIK, and SBK are effective in the treatment of myopia, which can effectively improve the uncorrected visual acuity and help the patients to recover their normal visual ability, but SMILE is more effective in tear film stability and corneal higher-order aberrations.

Mechanism of Myopic Defocus or Atropine for Myopia Control: Different or Similar Ways?

Introduction: Myopia is usually caused by excessive elongation of the eye during development. This condition is common worldwide. In clinical practice, the progression of myopia is commonly controlled through optical or drug measures, but the specific mechanisms underlying these two treatments remain unclear. To verify whether the effects of these two treatments on posterior-pole tissues are similar or different, we studied a set of common transcriptional changes in chicken models. Methods: Chicks were divided into four groups, and they were given the intervention measures of plus-lens induction, minus-lens induction, minus-lens induction with atropine injection, and minus-lens induction with saline injection. Then, the genetic changes in each tissue at the posterior pole were detected, and the results of different genes were compared. A semiquantitative real-time polymerase chain reaction method was used to further study the visually induced changes in the transcription of potential candidate genes. Results: Based on RNA sequencing (RNA-seq) analysis of the transcriptome, we identified variations between the differentially expressed transcripts in three tissues from the two treatment groups. Through Kyoto Encyclopedia of Genes and Genomes enrichment analyses, eukaryotic protein translation elongation factor 1α2 (EEF1A2) was enriched in the “leishmaniasis” pathway in the choroid and showed increased expression in both the plus-lens induction and injection atropine groups. The expression levels of selected genes verified by quantitative real-time PCR were concordant with the RNA-seq data. Conclusions: Overlapping differentially expressed mRNAs of only one-tenth could suggest a different mechanism of myopic defocus and intravitreal injection of atropine controlling myopia. EEF1A2 might play an important role in the choroid during the treatment of myopia.

Comparison of Long-Term Visual and Refractive Results of Transepithelial and Mechanical Photorefractive Keratectomy.

Objectives:The aim of the study was to present and compare 2 years results of mechanical photorefractive keratectomy (M-PRK) and transepithelial photorefractive keratectomy (T-PRK) for myopia.Methods:One hundred and nine eyes of 55 patients were included in this retrospective study. The mean age of the patients was 26.9±5.2 years. Forty-four eyes (40.4%) had M-PRK and 65 eyes (59.6%) had T-PRK. Follow-up time was 2 years. Refractive errors (RE), uncorrected visual acuity (UCVA), and high-order corneal aberrations were compared.Results:The mean RE was −2.33±0.88 D and the mean UCVA was 0.24±0.17 logMAR at baseline for M-PRK patients. At month 24, those measurements were changed to −0.27±0.32 D and 0.99±0.04 logMAR. The mean RE was 2.19±0.73 D and the mean UCVA was 0.23 ± 0.15 logMAR at baseline for T-PRK patients. At month 24, those measurements were changed to −0.14±0.32 D and 0.99±0.01 logMAR. The mean REs significantly decreased and the mean UCVA significantly increased after both type of surgeries (all p<0.001). In M-PRK group, 4 mm zone total corneal aberration and 6 mm total-coma-spherical corneal aberrations were statistically significantly increased in post-operative term. In T-PRK group, only 6 mm total-spherical corneal aberrations were statistically significantly increased in post-operative term. There was no serious complication during surgeries or follow-up time.Conclusion:M-PRK and T-PRK were a safe and effective in the treatment of myopia in 2 years term. Some high-order aberrations may be increase after those treatments.

PREVALENCE AND CONTROL OF MYOPIA AMONG CHILDREN IN PLEVEN, BULGARIA

Purpose: To observe the factors affecting the prevalence and control of myopia among children in Pleven, Bulgaria. Methods: A retrospective study was done. From March 2019 to March 2021, 404 consecutive patients from 3 to 18 years old with the main diagnosis myopia after cycloplegia passed through the private ophthalmology practice. The following signs were analyzed: age, sex, location, type and degree of myopia, review result and accompanying diseases. Results: The demographic profile of the evaluated children was: 43.8% males and 56.2% females (р&lt; 0.05); most of them are living in the city (89.2%). The most significant number of children with myopia were between 9 and 12 years old. Children with new onset myopia were 27.7% and 72.3% were with existing one. Patients between 8 and 18 years of age with existing myopia are more than those with new onset one (p &lt;0.05). There were 76.7% children with a low degree of myopia, 17.6% with a medium degree and 2.0% with a high degree. Without accompanying diseases were 65.6% of our patients. Conclusion: The control and treatment of myopia seem promising. However, it is necessary to develop a state policy for the prevention of children's eye health in Bulgaria.

Measurement of Myopia and Normal Human Choroidal Thickness Using Spectral Domain Optical Coherence Tomography

Myopia is a common ophthalmic deficiency. The structure and function of choroid layer is assumed to be associated with myopia. In this study, a laboratory developed spectral domain optical coherence tomography scanning system is used to image human eyes. The axial resolution of the system is about 7 μm, and the acquisition rate is 100 kHz. Firstly, a cross-sectional image was acquired by averaging 100 images from imaging posterior segment of each eye. The choroid thickness was measured by 11 discrete points. The average thickness of normal human eyes was (0.296 ± 0.126) mm, whereas the average choroid thickness of myopic eyes was (0.220 ± 0.095) mm. Afterwards, the T test is used to calculate the data statistically. The analysis of the final result is based on the average thickness measured and the thickness of each measuring point. There was a significant difference in choroid thickness between myopia and normal eyes (P value < 0.01), which indicates that the choroid thickness of myopia was significantly thinner than that of normal eyes. Besides, there are findings that the choroidal thickness in nasal side is thinner than that in the fovea and temporal side in each eye. The choroidal thickness on temporal side in myopia eye has the most significant difference comparing with that in normal eye. The comprehensive evaluation of myopia and normal choroidal thickness using spectral domain optical coherence tomography may provide an important reference for the development of medical methods for diagnosis and treatment of myopia.

Evalution of the state of the lipoperoxidation and enzymal antioxidant protection in treatment of high-grade complicated myopia

Evalution of the state of the lipoperoxidation and enzymal antioxidant protection in treatment of high-grade complicated myopia

Myopia: A Behavioral Approach for Prescribing and Vision Therapy

Myopia has reached serious epidemic proportions in many developed countries throughout the world, and is a public health issue with which the optometric profession is deeply concerned. Different clinical approaches are available to the optometrist for treatment of myopia. For the majority of patients, prescribing minus lenses to achieve 20/20 visual acuity at distance does little to prevent a patient from becoming more myopic or to improve vision function in the broadest sense, though it provides immediate improvement in distance visual acuity. A behavioral optometric clinical approach is presented in this paper to give the doctor a clear-cut strategy offering more alternatives to the patient with myopia. Employing this approach has the potential to prevent patients from developing myopia to levels higher than -2.00 diopters, reversing minus lens powers in patients that come to the optometrist already wearing a minus lens prescription, and reducing dependency on using minus lens prescriptions. Vision therapy is addressed as a procedure to improve a patient’s vision function in addition to visual acuity. Book retinoscopy is employed as a valuable technique to arrive at a training eyeglass prescription. At the completion of treatment, a patient typically improves in distance visual acuity, reduces minus lens powers, develops increased confidence in vision capabilities (with and without minus lens wear), develops an awareness and appreciation for additional aspects of vision such as space, forms, colors, patterns, periphery, and feels empowered that they have learned how to improve distance vision through self-initiated control.

First Experiences with Implantation of Phakic Lenses in Correction of Myopia in R. N. Macedonia

Abstract Objective: Analysis of visual acuity parameters in patients with moderate to high myopia and myopic astigmatism 1 year after treatment with phakic intraocular lenses. Material and methods: This was a retrospective study on 35 patients (52 eyes) with moderate to high myopia who were implanted with the Visian V4c phakic implantable Collamer lens (Staar Surgical, Nidau, Switzerland). Examined parameters were: uncorrected distance visual acuity (UDVA) and best corrected visual acuity (CDVA), manifest and cycloplegic refraction, intraocular pressure, and endothelial cell count. The investigated parameters were measured preoperatively, 1, 3, 6 and 12 months postoperatively. Results: In 17 patients, phakic lenses were implanted binocularly and in 18 patients monocularly. Preoperatively 34.62% of patients had CDVA from 0.9 to 1.0. One year after the surgery 48.08% of patients had UDVA from 0.9 to 1.0. Preoperatively 80.77% of patients had diopter range from -6.00 Dsph to -10.00 Dsph. At 1 year postoperatively 78.85% of patients were within 0.00 Dsph to -1.00 Dsph. Preoperatively, in patients with astigmatism -4 Dcyl to -2 Dcyl dominated, as opposed to significant improvement postoperatively when 94.23% had astigmatism ranging from -1.0 Dcyl to 0 Dcyl. Conclusion: The implantation of phakic lenses demonstrated a successful postoperative outcome in the treatment of myopia and myopic astigmatism. Visual acuity and refraction show a gradual and significant improvement in visual function parameters within 1 year of lens implantation.

Finite element analysis of the effect of local posterior sclera collagen cross-linking on eyeball shape

China is the country with high incidence of high myopia in the world. High myopia can cause severe vision impairment. So far, there is no effective treatment for high myopia in clinic. Scleral collagen cross-linking surgery has been proven to be effective in preventing animal eye axial elongation in vitro and in vivo. However, the influence of posterior scleral collagen cross-linking on the deformation of the whole eyeball is still unclear. In this study, finite element simulation were used to analyze the changes of eyeball shape and the position of light casting on the retina after posterior sclera cross-linking, and the mathematical algorithm was written to verify their similarity. The results showed that the shape of the whole eyeball was still very similar before and after cross-linking, and the diopter of the eyeball after cross-linking had little change, which had almost no effect on the position of light projection on the retina. Our results indicate that posterior sclera cross-linking wouldn't lead to distortion to the optometry, that is, the increase of elastic modulus in local scleral tissue after cross-linking wouldn't cause new problem of optometry and vision.

Reversal of Myopic Correction for Patients Intolerant to LASIK

Purpose To evaluate the outcome of the reversal of myopia correction in patients intolerant to LASIK. Methods This study is a retrospective and case series of patients who decided to reverse their previous myopic LASIK correction between July 2012 and July 2020. It was conducted at a private refractive surgery centre, Ismailia, Egypt. The patients were followed up after reversal treatment for one year. Primary LASIK and reversal treatment were performed by a 500 kHz Amaris excimer laser platform. The main outcomes included refractive predictability, stability, efficacy, and safety and any reported complications. Results This study included 48 eyes of 24 patients (6 male and 18 female patients). The average duration between the primary LASIK surgery and reversal treatment was 3.20 ± 0.30 months (range 3 to 4 months). Reversal treatment was bilateral in all patients. The mean age of the patients was 38 ± 1.9 years (range 37 to 45 yrs). After reversal, the mean postreversal cycloplegic refraction spherical equivalent was −1.82 ± 0.34 D (range −1.50 to −3.00 D). The mean ablation depth was 34.10 ± 7.36 μm (range 20 to 46 μm), and the mean of the central corneal thickness 12 months after reversal treatment was 510.2 ± 14.4 μm (range 515 to 487 μm). The mean keratometric reading was 42.6 ± 1.6 (range 42.5 to 44.8). The mean of CDVA was 0.2 ± 0.03 log MAR (range −0.10 to 0.4 log MAR). The mean optical zone of reversal treatment was 6.1 ± 0.3 mm (range 5.9 to 6.2 mm). UDVA was 0.4 log MAR in 87.5% of the patients, 0.5 log MAR in 8.3% of the patients, and 0.6 log MAR in 4.2% of the patients. CDVA remained unchanged in 83.3% of patients; 2.1% of the patients gained one line of CDVA (Snellen); 8.3% of the patients lost one line of CDVA; 6.3% of the patients lost two lines of CDVA. No cases of corneal ectasia were recorded. The only postoperative complications were flap microfolds in 3 eyes (6.25%). Conclusion In conclusion, this study demonstrates that reversal of myopic LASIK treatment is a safe, stable, and effective option for intolerant patients.

Analysis of the treatment effect of posterior scleral reinforcement on pathological myopia

Pathological myopia, a blinding eye disease, is the most common cause of visual impairment in Asian countries. The most obvious features of pathological myopia are the elongation of the eye axis, the appearance of posterior scleral staphyloma, and even degenerative changes in the retina and choroid, resulting in corresponding complications and ultimately leading to marked visual impairment. Controlling the elongated eye axis is a key factor in preventing the complications of pathological myopia. Posterior scleral reinforcement is the main surgical method to delay the elongation of the eye axis and treat the posterior scleral staphyloma. Although most studies have confirmed that posterior scleral reinforcement is effective in delaying axial elongation and treating myopia, some scholars hold negative views on this surgery. This article summarizes the relevant research results of posterior scleral reinforcement surgery in the treatment of pathological myopia, concerning patients' vision, refractive power, eye axis, and corneal curvature, and discusses the effectiveness of the surgery. (Chin J Ophthalmol, 2021, 57: 952-957).