The association of myopia progression with the morphological changes of optic disc and ß-peripapillary atrophy in primary school students.

PURPOSE: To study the association of myopia progression with the morphological changes of optic disc and ß-peripapillary atrophy (ß-PPA) in 8-11 years old primary school students. METHODS: This study was a prospective, school-based investigation. This study included 610 children (1008 eyes) who were continuously observed and had data available from 2016 to 2017 in the Sanhe Cohort Study of the Risk Factors for Myopia (SCSRFM). The children underwent a comprehensive eye examination including measurement of visual acuity, autorefractometry, and posterior segment of the eye. ß-PPA regions and optic disc ovality index were identified and measured on the fundus photographs. RESULTS: The prevalence of myopia was 72.62% (732/1008) in 2016. In myopic children, the prevalence of the vertical ß-PPA, the horizontal ß-PPA, and the oval optic disc were 75.68% (554/732), 75.96% (556/732) and, 11.61% (85/732) respectively. From 2016 to 2017, with the progression of vertical ß-PPA, horizontal ß-PPA, area of ß-PPA, and optic disc ovality index, the myopic diopter and the axial length (AL) were increased. The progression of horizontal ß-PPA was significantly correlated with the progression of myopic diopter and AL (all p < 0.05). The analysis on the distribution of progression rate of parameters in different groups found that the progression rate of horizontal ß-PPA, area of ß-PPA, and optic disc ovality index increased with the increase of the progression of diopter and AL. The progression of horizontal ß-PPA, area of ß-PPA, optic disc ovality index, and diopter in girls were greater than that in boys, and the progression of optic disc ovality index and diopter had a statistical significance (all p < 0.05). CONCLUSIONS: The 1-year follow-up study of the third-grade primary school students showed that with the progression of myopia and the growth of AL, ß-PPA and optic disc ovality index also changed. There was a positive correlation between the change of ß-PPA and optic disc ovality index and the progression of myopia diopter and AL.

Comparison of different pupil dilatation methods for phacoemulsification in eyes with a small pupil.

PURPOSE: To compare 6 methods for intraoperative pupil dilatation in eyes with insufficient pupil size during phacoemulsification. METHODS: This was a prospective case-control study. 99 microcoria cataract patients (120 eyes) were collected and were divided into 6 groups(20 eyes each group), and their pupils were dilated by bimanual stretching pupil (group I), pupil radial cut open(group II), mechanical pupil dilatation with iris-retractor hooks (group III), OASIS iris expander (group IV), and Malyguin-ring (Microsurgical company, America) (group V), B-HEX Pupil Expander (Med Invent Devics, India)(group VI),respectively. 3.0 mm clear corneal incision were used in phacoemulsification. All cases were followed up at 1 week and 1, 3, 6 months after the surgery. The best corrected visual acuity (BCVA), intraocular pressure(IOP), corneal endothelium cell density(ECD), pupil diameter(PD) of before and after surgery were compared. RESULTS: One same doctor finished all cataract surgeries successfully. The eyes' condition before surgery and at 6 months after surgery were compared. There were no significant statistical differences for the conditions of the eyes before surgery among six groups. The ECDs were better at 6 months postoperatively in group III and V, median values: 2114/mm2, 1961/mm2. PD was largest in group II (median value: 5.5 mm), which was significantly larger than other groups (Padjusted < 0.05). CONCLUSIONS: All 6 methods used in this study were effective for the mechanical dilatation of small pupils and didn't affect the postoperative visual acuity and intraocular pressure in microcoria cataract phacoemulsification. Iris-retractor hooks and the Malyugin Ring can reduce intraoperative corneal endothelium cell loss. Postoperative PD is larger when the iris was cut open radially.

Knockout of TGF-ß receptor II by CRISPR/Cas9 delays mesenchymal transition of Lens epithelium and posterior capsule opacification.

Posterior capsule opacification (PCO) is the most common postoperative complication of cataract surgery. Transforming growth factor-ß (TGF-ß) is related to epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) that is proven to induce PCO formation in clinical and experimental studies. In this study, CRISPR sequences targeting exon of TGF-ßRII were knocked out with lentiviral transfection in LECs. Rabbits' PCO model was established and recombinant adeno-associated virus (AAV) for transferring the gRNA of TGF ßRII were intravitreally injected. SgRNA inhibited TGF-ßRII expression and human LECs proliferation. In TGF-ßRII knockout group, LECs motility and migration were suppressed, N-cadherin and vimentin expressions were significantly decreased, whereas E-cadherin was increased. The animal model showed that TGF-ßRII knockout in vivo was effective in suppressing PCO. The current study suggested that the CRISPR/Cas9 endonuclease system could suppress TGF-ßRII secretion, which participates in the EMT procedure of LECs in vitro and PCO in vivo. These findings might provide a new gene-editing approach and insight into a novel therapeutic strategy for PCO.

Comparison of the accuracy of three intraocular lens power calculation formulas in cataract patients with prior radial keratotomy.

PURPOSE: To compare the accuracy of three intraocular lens (IOL) formulas in Chinese cataract patients with prior radial keratotomy (RK). METHODS: Medical records of cataract patients with prior RK at Beijing Tongren Hospital were retrospectively analysed. The absolute error (AE) was calculated as the absolute difference between the actual postoperative spherical equivalent and the predicted spherical equivalent. The AE and percentages of eyes with AE within 0.5D, 1.0D, and 2.0D for three formulas [Barrett True-K, Holladay 1 (D-K), Haigis] were calculated and compared. RESULTS: Forty-seven eyes of 28 cataract patients were included. The Median AE (MedAE) was significantly different among the three formulas (P < 0.001). The MedAE was lowest for the Barrett True-K formula (0.62), followed by the Haigis (0.76), and Holladay 1 (D-K) (1.16). The percentages of eyes with AE within 0.5D, and 1.0D were significantly different among the 3 formulas (P = 0.009, and P < 0.001). The Barrett True-K formula achieved the highest percentages (46.8%) of eyes with AE within 0.5D. Haigis achieved the highest percentages (70.21%) of eyes with AE within 1.0 D. CONCLUSIONS: Barrett True-K is the most accurate IOL power calculation formula among the 3 formulas and Haigis is an alternative choice. Considering the relatively lower accuracy of IOL formulas in cataract patients with prior RK, newer and more accurate IOL formulas are desirable.

Congenital coralliform cataract is the predominant consequence of a recurrent mutation in the CRYGD gene.

BACKGROUND: Congenital cataract is a leading cause of treatable childhood blindness and both clinically and genetically heterogeneous. Among the already characterized phenotypes, coralliform cataract is a rare special form of congenital cataracts. Although previous studies had shown that mutations in the γD-crystallin (CRYGD) can result in congenital coralliform cataracts, no conclusive genotype-phenotype correlation might be drawn. Here we aimed to identify the spectrum and frequency of CRYGD gene mutations in congenital coralliform cataracts of Chinese origin. METHODS: The medical records of 392 Chinese families with congenital cataracts were reviewed between January 2011 and December 2021. The families, clinically documented to have congenital coralliform cataracts, were screened for mutations in candidate CRYGD gene. The genomic DNA of all subjects was extracted from peripheral blood leukocytes. PCR amplified and direct sequencing were performed to identify the disease-causing mutation. RESULTS: A total of 12 families with coralliform cataracts were recruited in this study in the past 10 years, accounting for 3.1% of the families with congenital cataracts. Of the 12 families, all affected individuals presented with bilateral non-progressive coralliform cataracts since birth, with the best-corrected Snellen visual acuities ranging from 20/200 to 20/25. A recurrent c.70 C > A (p. P24T) mutation in CRYGD was identified in 10 families (83.3%) with congenital cataract, which co-segregated with all affected individuals and was not observed in unaffected family members or ethnically matched normal controls. CONCLUSIONS: The coralliform cataract is characterized by being bilateral, non-progressive and present at birth. A recurrent p.P24T CRYGD mutation occurs independently in 83.3% of the Chinese families with congenital coralliform cataracts and most likely represents a mutational hot spot, which underscore the relations between coralliform cataract and p.P24T CRYGD.

Prevalence and Clinical Characteristics of Myelinated Retinal Nerve Fibres in a Chinese Teleophthalmology System.

Purpose: To investigate the prevalence and clinical characteristics of myelinated retinal nerve fibre (MRNF) in a large teleophthalmology system.Methods: All records between January 2015 and December 2015 from Daheng Prust teleophthalmology system were reviewed by 2 ophthalmologists independently. MRNF was classified into continuous group and discontinuous group according to the relationship between MRNF patches and optic disc. The number, total area and location of MRNF patches were analysed. Concomitant ocular diseases were documented.Results: Out of 51469 subjects, MRNF was detected in 304 eyes of 263 subjects with a prevalence rate of 0.51 ± 7.1% per subject and 0.30 ± 5.4% per eye. Among 304 eyes with MRNF, 239 (78.6%) eyes were in continuous group and 65 (21.4%) eyes were in discontinuous group. Single MRNF patch was found in 249 (81.9%) eyes and multiple MRNF patches were found in 55 (18.1%) eyes. MRNF of small size was found in 150 (49.3%) eyes. The ratios of multiple MRNF patches and small-sized MRNF in the continuous group were significantly higher than those in the discontinuous group (P = .014 and P < .001). In continuous group, the MRNF patches were located most frequently in the superior region (68.6%) of the optic disc; In discontinuous group, the MRNF patches were located most frequently in the inferotemporal region (38.5%) of the retina. Epiretinal membrane (12 eyes, 3.9%) was the most common concomitant ocular disease.Conclusion: MRNF is uncommon in China. MRNF usually presents unilaterally and as a single small whitish patch that is connected with optic disc.