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With the rapid development of science and technology and the wide application of electronic products, the number of patients with high myopia is gradually increasing. Meanwhile, owing to the continuous optimization of surgical skils and the continuous advancement in materials of posterior chamber intraocular lens and manufacturing processes, implantable collamer lens(ICL)V4c implantation has gradually become one of the main surgeries for the treatment of high myopia. In the rapid era of social information, people pay more attention to the long-term efficacy after ICL V4c implantation, they not only want clear vision, but also the pursuit of visual comfort and durability. Therefore, this paper will specifically discuss the research progress of the post-implantation efficacy of ICL V4c with at least 2 a of follow-up observation within 3 a, aiming to review the latest research progress on the long-term efficacy of ICL V4c implantation from the three dimensions of visual quality, safety, efficacy and stability and possible surgical complications after ICL V4c implantation.
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The foveal avascular zone(FAZ)is the most sensitive region of the retina, which is interconnected by the macular capillary plexus. Its morphology can indirectly reflect the alterations of macular microcirculation. With strong repeatability and reliability, optical coherence tomography angiography(OCTA)can non-invasively visualize and quantify the FAZ. The great value of OCTA makes it an important supplemental examination tool in ophthalmology and other professions. The area and perimeter of FAZ have been demonstrated to be an effective clinical diagnostic indicator in high myopia, diabetic retinopathy, glaucoma and other ocular diseases. In recent years, the geometry of FAZ has also proven to have clinical value. The parameters describing the geometry of FAZ, such as circularity index, acircularity index and axial ratio, provide a new perspective for ocular disease research. The comprehensive investigation of the morphological characteristics of the FAZ is helpful to explore the pathological mechanism of the occurrence and development of ocular diseases, predict preclinical changes, make pathological stages of the disease precise, and provide a theoretical basis for monitoring the disease's progression and assessing patients' visual prognosis.
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AIM: To evaluate the pathogenic variants of the SCO2(OMIM 604272)gene in patients with high myopia from Enshi Tujia and Miao Autonomous Prefecture of China.METHODS: A total of 384 patients with high myopia whose spherical refractive error was ≤ -6.00 D and whose axial length was ≥26.00 mm in at least one eye were recruited. DNA was extracted by the phenol-chloroform method from 5 mL of peripheral venous blood. Sanger sequencing was performed to identify pathogenic variants in exon 2 of SCO2. The detected variants were evaluated via in silico prediction software. A total of 288 people from the same district were included as the normal control cohort.RESULTS: Seven variants were detected, namely, four synonymous variants(c.201C>T/p.=, c.576C>T/p.=, c.633A>C/p.=, c.780T>C/p.=.), two missense variants(c.187A>G/p.Ile63Val, c.59G>C/p.Arg20Pro)and one nonsense variant(c.544C>T/p.Gln182*). The two missense variants were not damaging, as predicted by PolyPhen2, SIFT and Provean. The novel nonsense variant(c.544C>T/p.Gln182*)cannot be found in the 1000 Genomes Project and was not identified in 288 normal controls. Variant Taster suggested that the nonsense variant site was conserved.CONCLUSION: The newly identified nonsense mutation may be responsible for high myopia of the patients in our cohort. SCO2 is associated with high myopia, while the incidence of SCO2 variants in high myopia in this cohort was as low as 1/384; the nonsense mutation may be a scarce variant of high myopia in the Enshi Tujia and Miao Autonomous Prefecture of China.
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Objective:To systematically evaluate the efficacy of phacoemulsification and intraocular lens (IOL) with and without capsular tension ring (CTR) in patients with high myopia and cataract.Methods:MEDLINE, EMBASE, Cochrane Library, and Chinese databases including CNKI, Wanfang Data, and VIP databases were searched from their establishment to October 2020 to obtain peer-reviewed clinical studies comparing the efficacy of cataract phacoemulsification and IOL implantation combined with CTR implantation (experimental group) and cataract phacoemulsification and IOL implantation (control group) in patients with high myopia and cataract.Literature screening, data extraction and methodological quality assessment were implemented based on inclusion and exclusion criteria.A meta-analysis of postoperative best corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution unit, posterior capsular opacification (PCO), capsular contraction syndrome (CCS), retinal detachment (RD) was performed using Revman 5.3 software with mean difference ( MD) and odds ratio ( OR) describing the effect sizes of measurement data and count data, respectively. Results:Eight studies with 2 085 eyes were included in this study, including 1 054 eyes in the experimental group and 1 031 eyes in the control group.Meta-analysis showed that there was no significant difference in BCVA between the two groups at 1 week, 1 month, and 3 months after surgery, but the improvement in BCVA at 6 months after surgery was significantly better in the experimental group than in the control group ( MD: -0.11; 95% CI: -0.15--0.07; P<0.01). The incidence rates of postoperative PCO ( OR: 0.24; 95% CI: 0.15-0.36; P<0.01) and CCS ( OR: 0.08; 95 % CI: 0.01-0.65; P=0.02) and RD ( OR: 0.21; 95% CI: 0.05-0.82; P=0.02) were lower in the experimental group than in the control group, and the differences were statistically significant. Conclusions:The combination of CTR in the treatment of patients with high myopia and cataract can improve the postoperative visual quality and reduce the incidence of postoperative PCO, CCS and RD.
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Objective:To analyze the genotype of hereditary eye diseases with early-onset high myopia (eoHM) and its relationship with phenotype.Methods:The families with eoHM were collected in Ningxia Eye Hospital from January 2019 to June 2020.The medical records of the probands and their family members were inquired and recorded in detail, and the relevant ocular examinations were performed.Peripheral venous blood samples were collected from patients and their family members, and whole-genome DNA was extracted.Sequence capture sequencing technology was applied to screen for disease-causing gene mutations in probands.The detected suspected pathogenic variants were verified by Sanger sequencing and were analyzed by family cosegregation analysis.According to ACMG guidelines, the pathogenicity of novel variants was evaluated.The original literature about hereditary eye diseases with eoHM was searched to analyze the relationship between mutated genes and clinical phenotype.This study protocol adhered to the Declaration of Helsinki.All subjects or their guardians were informed of the purpose and procedure of the study and signed the informed consent form.The study protocol was approved by the Ethics Committee of the People's Hospital of Ningxia Hui Autonomous Region (No.2016018).Results:A total of 20 eoHM families were collected, among which pathogenic variants associated with inherited eye diseases were detected in 8 families.Of the 8 probands, two were diagnosed with familial exudative vitreoretinopathy, one with X-linked retinitis pigmentosa, one with congenital stationary nightblindness, one with Stickler syndrome, one with achromatopsia, one with Leber congenital amaurosis, and one with gyrate atrophy of the choroid and retina.The first diagnosis age of the 8 probands was 4-7 years old, and they were all diagnosed as high myopia, with a refractive status ≤-6.00 DS.Genetic tests showed that the 8 probands carried a heterozygous variant c. 313A>G (p.M105Val) in FZD4 gene, a heterozygous variant c. 14_15insAAGA (p.Asp5fs *) in TSPAN12 gene, a heterozygous frameshift variant c. 2234_2237del (p.Arg745fs) in RPGR gene, a compound heterozygous variant of c. 481C>T (p.Gln161Ter *) and c. 355>T (p.Arg119Cys *) in GPR179 gene, a frameshift variant c. 1659_1660insACGGTGACCCTGGCCGTCCTGG (p.Pro554fs *) in COL2A1 gene, a compound heterozygous variant of c. 1811C>T (p.Thr604Ile *) and c. 967G>A (p.Gly323Ser) in PDE6B gene, a compound heterozygous variant of c. 604_619delTCCACGGCACTCAGGG (p.Ser202fs *) and c. 995G>C (p.Arg332Pro) in GUCY2D gene, a homozygous variant c. 772C>T (p.Pro241Leu) in OAT gene.Seven of them were novel variants.Compared with the previous literature, the clinical and gene phenotypes of the 8 families were analyzed in detail in this study, which provided the basis for the diagnosis of hereditary eye diseases with eoHM. Conclusions:EoHM is closely related to some hereditary eye diseases, which may be the reason for the early diagnosis of children and an important clue for clinicians to detect potential hereditary eye diseases.Further clinical evaluations of ocular structure and function as well as genetic screening in children with eoHM are recommended.
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Posterior staphyloma (PS) refers to the local abnormal bulge of the posterior wall of the eyeball, which is one of the common pathological changes in high myopia.The appearance of PS is often accompanied by changes in fundus microstructure such as sclera, choroid and Bruch membrane.The abnormality of fundus microstructure leads to the decrease of its resistance to the expansion of ocular axis, or causes the remodeling of tissue structure in the corresponding area, resulting in the change of microvascular structure, and then giving rise to abnormal blood circulation in the posterior pole.The microcirculatory changes may be followed by changes in fundus microstructure, seriously affecting the visual acuity of the affected eyes.There is still no clear conclusion on the pathogenesis of PS in the world, and there are no good preventive measures or treatment methods.This article reviewed and summarized the interaction between PS, fundus structure and microcirculation in high myopia, so as to provide a theoretical basis for exploring the pathogenesis, prevention and treatment of PS and improving the visual function of high myopia.
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AIM: To investigate the influencing factors of vault after the posterior chamber phakic refractive lens(PC-PRL)implantation for patients with super high myopia.METHODS: Retrospective case study. A total of 40 patients with super high myopia(77 eyes)who underwent PC-PRL implantation in the Haixiang Eye Hospital from January 2019 to January 2021 were selected. They were followed up for at least 2a, postoperative anterior segment parameters, such as the uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), central anterior chamber depth(ACD), anterior chamber volume(ACV), anterior chamber angle(ACA), lens thickness and vault were evaluated, and then the influencing factors of postoperative vault were analyzed.RESULTS: The UCVA and BCVA of the patients significantly improved after PC-PRL implantation(P<0.001). Average safety index(postoperative BCVA/preoperative BCVA)was 1.36±0.32, and average effective index(postoperative UCVA/preoperative BCVA)was 1.23±0.31 in 2a after surgery. The vault in 2a after surgery was correlated with preoperative ACD, ACV, ACA and lens thickness, and the preoperative ACV and lens thickness had significant impact on vault in 2a after surgery.CONCLUSIONS: The PC-PRL implantation is safe and effective in super high myopia, and it can significantly improve visual acuity. Furthermore, preoperative ACV and lens thickness are important influencing factors of postoperative vault.
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AIM: To investigate the clinical efficacy of pars plana vitrectomy(PPV)combined with inverted internal limiting membrane flap technique in the treatment of macular hole retinal detachment(MHRD)in high myopia.METHODS: A retrospective clinical study was conducted. A total of 63 patients(64 eyes)with high myopia and MHRD who treated at our hospital from October 2017 to October 2021 were selected as research subjects. They were divided into two groups according to different surgery, with 34 cases(35 eyes)who received PPV combined with inverted internal limiting membrane flap technique in group A, and 29 cases(29 eyes)received PPV combined with internal limiting membrane peeling in group B. The patients were followed up for 6mo. The two groups were compared in terms of the hole closure rate, the reduction rate of retinal detachment and best corrected visual acuity(BCVA)before operation and at 1wk, 1, 3 and 6mo after operation, and the postoperative complications were recorded.RESULTS: The hole closure rate within 6mo after operation was significantly higher in group A than in group B(P&#x003C;0.05), but there was no statistically significant difference in the reduction rate of retinal detachment(P&#x003E;0.05). The BCVA of the two groups was significantly improved over time after operation(P&#x003C;0.05). There was no statistically significant difference in BCVA between the two groups before operation and at 1wk, 1, 3 and 6mo after operation(P&#x003E;0.05). Complications were observed in the two groups, but there was no statistically significant difference in the incidence of complications between the two groups(P&#x003C;0.05).CONCLUSION: PPV combined with inverted internal limiting membrane flap technique is safe and effective in the treatment of MHRD in high myopia, which can effectively improve the patients' BCVA and the hole closure rate without influence on intraocular pressure.
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Myopia is a harmful ophthalmic disease that may change the activity of the visual cortex and affect the corresponding neural function. At present, the incidence rate of myopia in China has been rising unprecedentedly, especially in high myopia(HM). Therefore, efficacious prevention and treatment of myopia are extremely important. However, since the specific pathogenesis of myopia has not been clarified so far, it is difficult to achieve the prevention and control of the disease at its source. Recently, there have been studies on the pathogenesis of myopia from the perspective of genetics, environment, neurotransmitters, etc., but few studies have explored the neuroimaging mechanism of myopia from the perspective of brain structure and function. With the development of magnetic resonance imaging(MRI)technology, brain images gradually appear in the study of myopia-related mechanisms. Therefore, this paper summarizes the research on myopia-related brain images, to provide an important reference for the clinical prevention and control of myopia.
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High myopia is a state of refractive error with myopia over -6.00D. High myopia is typically accompanied by multiple fundus lesions, thus making patients with high myopia suffer from varying degrees of impairment in visual function. As an emerging auxiliary way in ophthalmology, optical coherence tomography angiography(OCTA)can efficiently and non-invasively obtain microvascular stratified images of the retina and choroid and quantitatively analyze blood flow signals. Since the advent of OCTA, there have been numerous studies observing fundus changes in those with high myopia through OCTA. In this paper, some studies in which OCTA is applied to obtain retinal and choroidal thickness from patients with high myopia are reviewed, with a view to revealing the correlation between high myopia and the parameters such as retinal thickness, choroidal thickness, vessel density and the area of the foveal avascular zone and providing novel ideas to deeply investigate the mechanism of high myopia and delay the occurrence and development of high myopia.
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AIM: To evaluate the accuracy of SRK/T, Haigis, Barrett Universal II and Wang-Koch modified SRK/T formula in the operation of cataract complicated by super-high myopia.METHODS: A total of 44 cases(52 eyes)with super-high myopia complicated with cataract who underwent phacoemulsification with tension ring implantation combined with intraocular lens implantation in our hospital from January 2020 to June 2021 were collected. SRK/T, Haigis, Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula were used to calculate the postoperative reserved diopter before surgery, and the actual diopter was measured by comprehensive optometry at 3mo after surgery. The mean absolute refractive error(MAE)of four formulas was obtained to evaluate the accuracy of the calculation formula.RESULTS: The MAE of SRK/T formula, Haigis formula, Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula were 0.86(0.56, 1.20), 0.79(0.56, 1.16), 0.68(0.30, 0.87), 0.65(0.43, 0.75)D, respectively, and MAE of SRK/T formula and Haigis formula were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula(P<0.01). According to preoperative corneal curvature(K), enrolled patients were divided into K >46D group(12 eyes), 44D< K ≤46D group(24 eyes), and K ≤44D group(16 eyes). The MAE of SRK/T formula and Haigis formula were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula in the three groups(P<0.01). According to preoperative axial length(AL), patients were divided into AL ≤30 mm group(24 eyes)and AL >30mm group(28 eyes). The MAE of SRK/T formula and Haigis formula in two groups were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula(P<0.05).CONCLUSIONS: Wang-Koch modified SRK/T formula and Barrett Universal Ⅱ formula are more accurate in predicting the degree of intraocular lens in patients with super-high myopia complicated with cataract.
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AIM: To evaluate the visual quality of patients with high myopia and cataract who received micro binocular single vision implantation of Tecnis Symfony intraocular lens(IOL), hybrid implantation of Tecnis Symfony IOL and Tecnis ZMB00 multifocal IOL, and binocular implantation of AcrySof IQ Panoptix IOL.METHODS: A prospective non-randomized controlled study was conducted to select patients with high myopia and cataract who underwent phacoemulsification combined with IOL implantation in the First Affiliated Hospital of Baotou Medical College from August 2020 to March 2022. According to the different IOL implantation schemes selected by patients, they are divided into micro single vision group, hybrid group and trifocal group. The postoperative follow-up was 3mo. The observation indexes included uncorrected far(5m), middle(80, 60cm)and near(33cm)visual acuity at 3mo after operation, contrast sensitivity(CS), uncorrected defocus curve under far vision, subjective visual quality score and light interference at 1 and 3mo after operation.RESULTS: There was no significant difference among the three groups in uncorrected far(5m)and middle(60cm)visual acuity at 3mo after operation(P<0.05); Uncorrected middle(80cm)distance visual acuity in the micro single vision group was similar to that in the hybrid group, and both were better than that in the trifocal group(P<0.05); Uncorrected near(33cm)distance vision of the hybrid group showed the best, followed by the trifocal group, and the lowest was in the micro single vision group(all P<0.05). The CS of dark light plus glare(12, 18c/d)was the best in the trifocal group, followed by the hybrid group, and the lowest was in the micro single vision group(all P<0.05). The defocus curve at 3mo after operation showed a span of +1.00～-3.00D, and the visual acuity of the three groups was better than 0.3 LogMAR; In the span of -1.00～-1.25D, the visual acuity of the hybrid group and micro single vision group was better than that of the trifocal group(all P<0.05); In the span of -3.00～-3.50D, the visual acuity of the hybrid group was the best, followed by trifocal group, and the lowest was in the micro single vision group(all P<0.05). At 3mo after operation, there was no significant difference in subjective visual quality scores among the three groups(P<0.05). Light interference in the micro single vision group was higher than that of the other two groups at 1mo after operation(P<0.05), and it decreased in the three groups at 3mo after operation, with no statistical significance(P<0.05).CONCLUSION: The three IOL implantation schemes can provide excellent visual quality for patients with high myopia and cataract. The vision of the micro single vision group and the hybrid group is better in the span of -1.00～-1.25D, and the hybrid group performs the best near vision in the span of -3.00～-3.50D. Although the design of micro single vision can make up for the weakness of Symfony IOL's lack of near vision, it is still worse than the hybrid group and the trifocal group.
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With the prevalence of myopia in Asia, the prevalence of high myopia is gradually increasing, and high myopia has undoubtedly become a public health problem in Asia and even around the globe. As a relatively common pathological change in the eyes of patients with high myopia, optic disc tilt may also become a risk factor for diseases such as glaucoma and macular degeneration, thereby increasing the risk of visual impairment. However, the mechanism of optic disc tilt in high myopia and the role of optic disc tilt in the aggravation of high myopia complications still needs to be further explored. Therefore, this article collects and organizes relevant literatures on optic disc tilt, and makes a comprehensive discussion on the mechanism of optic disc shape changing caused by high myopia and the impact on various complications, so as to provide a certain basis for clinical diagnosis and treatment of high myopia and its complications.
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AIM: To observe the efficacy of moderate and high myopia patients with vault greater than 1 000μm after implantation of phakic posterior chamber implantable contact lens(ICL).METHODS: A total of 42 patients(73 eyes)who received ICL implantation in the hospital and had postoperative vault greater than 1 000 μm between January 2014 and January 2017 were selected and retrospectively studied. Changes in visual acuity, intraocular pressure, corneal endothelial cell density, anterior chamber-related parameters(chamber angle, central anterior chamber depth, anterior chamber volume)and vault were compared among patients before surgery, at 1, 3, 6mo and 1a after surgery and at the last follow-up.RESULTS: The uncorrected visual acuity(UCVA)at 1, 3, 6mo and 1a after surgery and at the last follow-up was better than that before surgery(all P&#x003C;0.05), and the chamber angle, central anterior chamber depth and anterior chamber volume were smaller or lower than those before surgery(all P&#x003C;0.05), but there were no statistical differences in UCVA, chamber angle, central anterior chamber depth and anterior chamber volume at each time point after surgery(all P&#x003E;0.05). The intraocular pressure at 1mo after surgery was lower than that before surgery(P&#x003C;0.05), but the intraocular pressure at 3, 6mo and 1a after surgery and at the last follow-up was not statistically different from that before surgery(all P&#x003E;0.05). There was no statistical significance in the corneal endothelial cell density at 1, 3, 6mo and 1a after surgery and at the last follow-up compared with that before surgery(all P&#x003E;0.05). The vault at 1, 3, 6mo and 1a after surgery and at the last follow-up showed a decreasing trend, and the difference was statistically significant at each time point after surgery(all P&#x003C;0.05).CONCLUSION: The short-term and long-term efficacy are better in moderate and high myopia patients with vault greater than 1 000 μm after ICL implantation, and there are no significant effects on the intraocular pressure and corneal endothelial cell. The postoperative anterior chamber structure is relatively stable and the vault tends to decrease over time. In most cases, close observation is sufficient and intraocular lens replacement is generally not required.
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AIM: To measure the indexes including postoperative distance, middle, near visual acuity and near stereopsis vision of patients with high myopia cataract and corneal astigmatism by femtosecond laser, which can quantify the diameter of capsulorhexis opening, and to evaluate the availability and necessity of Toric intraocular lenses(IOL)in high myopia.METHODS: Prospective case-control study. Patients with binocular high myopia cataract and corneal astigmatism who undergone femtosecond laser-assisted cataract surgery in our hospital were selected, and they were divided into two groups, with 20 cases(40 eyes)in group A(Toric IOL)and 20 cases(40 eyes)in group B(IQ IOL). Indexes, including preoperative corneal astigmatism and spherical equivalent and best-corrected distance visual acuity, uncorrected middle visual acuity, uncorrected near visual acuity, residual refractive astigmatism, near stereopsis acuity, total high-order aberration and total spherical aberration, were measured postoperatively at 7d, 1 and 3mo.RESULTS: The uncorrected middle and near visual acuity, Titmus near stereopsis acuity and residual astigmatism at 7d, 1 and 3mo after surgery were significantly improved in the Toric IOL group than the non-Toric group(all P&#x003C;0.05). The dependence on glasses was reduced. The postoperative best-corrected distance visual acuity, total high-order aberration and total spherical aberration of the two groups showed no statistically significant differences(all P&#x003E;0.05).CONCLUSIONS: The implantation of Toric IOL in patients with high myopia cataract and corneal astigmatism can effectively correct corneal astigmatism, improve postoperative uncorrected middle and near visual acuity and near stereopsis visual function, reduce postoperative dependence on glasses and enhance binocular stereopsis visual function.
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AIM: To investigate the changes in anterior chamber depth(ACD), axial length(AL), and corneal curvature(K)after operation in patients with high axial myopia combined with cataract, and the effect on postoperative mean refractive error(MFE)by different surgical approaches.METHODS: A total of 126 patients(126 eyes)performed cataract combined with intraocular lens(IOL)implantation were selected and divided into 3 groups according to different surgical approaches and axial length. Group A included 42 patients(42 eyes)who had cataract combined with high myopia and were performed cataract phacoemulsification combined with IOL implantation; Group B included 42 patients(42 eyes)who had cataract combined with high myopia and underwent small incision cataract extracapsular extraction combined with IOL implantation; Group C included 42 patients(42 eyes)who had cataract with normal axial length and underwent cataract phacoemulsification combined with IOL implantation. Then, the ACD, AL, K value and visual acuity of the three groups at 1d before operation and 3mo after operation were measured, and statistical analysis was performed.RESULTS: The differences in the mean values of preoperative and postoperative changes in ACD(△ACD)and AL(△AL)between groups A and B showed no statistical significance. The differences in the mean values of △ACD and △AL between groups A and C and groups B and C were both statistically significant(both P&#x003C;0.01). △ACD and △AL in all three groups showed positive correlation(rA=0.855, rB=0.856, rC=0.639, all P&#x003C;0.05). Furthermore, preoperative AL, △AL, △ACD and MFE in all three groups showed positive correlation(rA=0.874, 0.877, 0.858, rB=0.875, 0.879, 0.858, rC=0.428, 0.766, 0.862, all P&#x003C;0.05). The standardized regression coefficients of groups A and B were △AL&#x003E;△ACD(1.32 and 1.31 times), and the standardized regression coefficients of group C were △ACD&#x003E;△AL(1.66 times).CONCLUSION: Different surgical procedures had no significant effect on the postoperative K value and MFE in patients with high axial myopia combined with cataract, of which main influencing factor is the change in the AL before and after surgery. The postoperative MFE in patients with normal AL was more due to the change of ACD.
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High myopia is the main cause of visual impairment in the world. With the development of society, the myopia rate is increasing year by year. The development of high myopia is closely related to the progressive extension of the eye axis, and a series of fundus changes will inevitably occur with the extension of the eye axis, such as comus, lacquer cracks, choroidal neovascularization, macular choroidal atrophy, retinal detachment, posterior scleral staphyloma, etc. At present, characterized by younger age and high degree, myopia has become the main cause of blindness in China. This paper briefly summarizes the latest research on the morphological changes of the optic disc, macula, retina, choroid and sclera of high myopia, aiming to provide references for the development of intelligent prediction models, clinical diagnosis and further research on the treatment measures in combination with the fundus morphology of high myopia.
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AIM: To compare the accuracy of different intraocular lens(IOL)calculation formulas in cataract patients with axial length longer than 28mm and a history of radial keratotomy(RK).METHODS: Retrospective study. The medical records of 19 cataract patients(29 eyes)after RK and with axial length longer than 28mm who underwent cataract surgery from January 2011 to July 2020 in Beijing Tongren Hospital were analyzed. The absolute error(AE)of the difference among three different formulas was calculated. AE refers to the absolute value between the actual spherical equivalent after cataract surgery and the spherical equivalent predicted by the IOL formula. The AE values of the three formulas and the percentages of eyes with AE≤0.5, 0.75, 1.0, and 2.0D were calculated and compared.RESULTS: The AE values of the three formulas were significantly different(χ2=8.759, P=0.013). The Barrett True-K formula had the smallest median AE, which was only 0.62(0.20, 1.15)D, followed by the Haigis formula 0.76(0.34, 1.26)D, and the Holladay 1(D-K)formula had the largest 1.01(0.49, 1.62)D. The percentages of affected eyes with AE ≤0.5, 0.75, 1.0, and 2.0D for the Barrett True-K formula were 48%, 59%, 69%, and 93%, which were equal to or higher than the other two formulas.CONCLUSION: The Barrett True-K formula is more recommended among the three formulas for cataract patients after RK and with axial length longer than 28 mm.
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AIM: To analyze the effect of full-femtosecond small incision lenticule extraction(SMILE)on the treatment of high myopia based on propensity score matching.METHODS: A total of 48 cases(48 eyes)of high myopia patients who underwent SMILE surgery in our hospital from May 2019 to May 2021 were selected as the observation group, and 48 cases(48 eyes)of high myopia patients who underwent FS-LASIK surgery were matched using propensity score matching as the control group. Follow up for 6mo after surgery, the changes in cylindrical, central corneal thickness, uncorrected visual acuity(UCVA), corneal endothelial cell related indicators [percentage of hexagonal endothelial cells(6A), coefficient of variation(CV)of endothelial cell area, central corneal endothelial cell density(ECD)] and corneal biomechanical indicators [simulated Goldman intraocular pressure(IOPg), corneal hysteresis(CH), corneal resistance factor(CRF), corneal compensated intraocular pressure(IOPcc)] between the two groups were compared, and the incidence of complications in both groups of patients was recorded.RESULTS: Both groups of patients showed significant improvements in cylindrical and UCVA at 3 and 6mo after surgery, as well as decreased central corneal thickness, corneal endothelial cells, and corneal biomechanics related indicators. The changes in the observation group were more significant(all P<0.05). During the follow-up period, there was no significant difference in the incidence of complications between the observation group and the control group(8% vs. 17%, P>0.05).CONCLUSION: SMILE has a definite effect on patients with high myopia and is helpful to improve visual acuity.
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AIM:To observe the effect of implantable collamer lens V4c(ICL V4c)implantation on high myopia, and the changes in anterior segment morphology.METHODS:A prospective study was conducted on 100 patients(200 eyes)with high myopia who were treated with ICL V4c implantation in the hospital from February 2018 to March 2021. The best corrected visual acuity(BCVA), uncorrected visual acuity(UCVA), intraocular pressure, higher-order aberration, anterior segment morphology [iridocorneal angle(ICA), central anterior chamber depth(ACD), anterior chamber volume(ACV), central corneal thickness(CCT)and K-value(K)], photopic and scotopic contrast sensitivity before operation and 6 and 12mo after operation were comparatively analyzed.RESULTS:All patients were followed-up. UCVA and BCVA were significantly improved at 6 and 12mo after operation(P<0.05). Total higher-order aberration, horizontal coma and vertical coma showed no significant difference before and after operation(P>0.05). Spherical aberration, ICA, ACD and ACV at 6 and 12mo after operation were significantly smaller than those before operation(P<0.05). Under photopic state, the contrast sensitivity of 3.0 and 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P<0.05). Under scotopic state, the contrast sensitivity of 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P<0.05); there was no significant difference in CCT, K, or intraocular pressure before and after operation(P>0.05).CONCLUSION:Although ICA, ACD and ACV in patients with high myopia are reduced after ICL V4c implantation, the operation can effectively improve visual acuity and visual quality.