Study on the myopia control effect of OK lens on children with different corneal curvature

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Method: A total of 178 myopic children admitted to our hospital from April 2019 to July 2021 were selected and grouped according to the baseline (at enrollment), and the children were divided into three groups, namely axial group (corneal curvature 41.5D, n=58), curvature group (corneal curvature 44D, n=55), and mixed group (41.5D corneal curvature 44D, n=65). All the children were treated with ok lens; comparing the growth rate of refraction, axial length, corneal curvature and axial axis respectively, and analyzing the prevention and control effect of myopia in different cycles and whether the prevention and control effect of different types of myopia were different. Result: The axis and refraction of the three groups improved within 2 years after wear, but the corneal curvature in the three groups showed a decreasing trend; After comparing the refraction, corneal curvature and axial length after wear, the refraction, corneal curvature and axial length were significantly better than those before wear (P <0.05). The growth rate of the axial axis of patients in the half-annual cycle decreased significantly, and the increase of axial axis also showed a decreasing trend. The difference between the increase of axial axis in the half year, 1 year, 1.5 years and 2 years after wearing the mirror was not significant (P> 0.05). In addition, corneal curvature in all patients in the study decreased after lens wear, and there was significant differences in corneal curvature between the axial and curvature groups (P <0.05). At the same time, the axial growth was significantly higher than that in the curvature and mixed groups (P <0.05). Conclusion: There is a close correlation between corneal curvature and the effectiveness of OK lens treatment. Compared to children with flat corneal curvature, OK lens has a more ideal effect on controlling the axial length of the eyes in children with steep corneal curvature, but has less impact on naked eye vision. Children Myopia Corneal curvature OK mirror Eye axis length Introduction Myopia is a common clinical eye disease, which is characterized by abnormal elongation of the eyeball and increased refractive power. The disease is also a serious public health problem, with a high prevalence rate, about 3.4%-42.2% in European and American countries, and about 13.8%-70.9% in China [1]. Among them, children have a high incidence of myopia. Once myopia occurs, it will show a progressive trend and is irreversible, and the development rate can be slowed down until early adulthood [2]. Without timely intervention, it will progress to high myopia, which may induce a series of serious eye complications such as retinal detachment and glaucoma, and have a serious impact on the quality of life of patients. Therefore, it is clinically believed that myopia prevention and control should be paid attention to [3]. Among them, ok lenses, also known as orthokeratology lenses, can effectively delay the progression of myopia and control the growth of axial length [4-5]. Although many studies have confirmed the effect of ok lens on myopia control, the treatment effect of this technique is affected by many factors. Among them, corneal curvature is an important eyeball biological parameter, and abnormal steepening of corneal curvature is a common cause of myopia [6-8]. Studies have reported that corneal curvature may be an important factor for the therapeutic effect of ok lens [9]. Another study [10] reported that corneal curvature was not an independent influencing factor for the treatment effect of ok lens. At present, there is still some controversy about whether corneal curvature will affect the efficacy of ok lens. Based on this, this study will analyze the effect of ok lens on myopia with different corneal curvature, in order to clarify the relationship between corneal curvature and the therapeutic effect of ok lens. The trial is reported as follows: 1 Materials and Methods 1.1 General Information A total of 178 myopic children admitted to our hospital from April 2019 to July 2021 were selected and grouped according to different corneal curvature at baseline. The children were divided into three groups: axial group (corneal curvature ≤ 41.5D, n = 58), curvature group (corneal curvature ≥ 44D, n = 58), and axial group (corneal curvature ≥ 44D, n = 58). n = 55) and mixed group (41.5D ≤ corneal curvature ≤ 44D, n = 65). Among them, there were 58 patients in the axial group, including 28 males and 30 females, aged 6–15 years, with an average age of 10.24 ± 1.27 years. There were 55 patients in the curved group, including 30 males and 25 females, aged from 6 to 15 years, with an average age of 10.37 ± 1.25 years. There were 65 patients in the mixed group, including 31 males and 34 females, aged 6–15 years, with an average age of 10.29 ± 1.30 years. There were no significant differences in baseline data (gender and age) among the three groups (P > 0.05). Inclusion criteria: (1) school-age children aged 6–15 years who met the diagnostic criteria for myopia [ 11 ]; (2) no previous history of wearing ok lenses; (3) The informed consent was signed by the family members of the children. Exclusion criteria: (1) presence of dry eye, acute ocular inflammation, other ocular organic diseases or contraindications to ok lens; (2) the presence of neurological or systemic diseases affecting refractive development; (3) pathological myopia. Methods All children were treated with ok lens, the operation was as follows: wearing the Euclidean OK lens, the inner surface of the lens was an inverse geometric four-arc design (Boston Equalens high oxygen permeability material), the diameter/central thickness was 10.6 mm/ 0.2 mm. The clinicians determined the parameters according to the patient's specific eyeball biological characteristics (corneal curvature, diopter, etc.), and informed the children and their families to wear ok lenses correctly, and professional technicians guided the maintenance of the lenses. Continuous night wear, wear 8–10 hours per night, continuous wear 12m, no need to wear any glasses during the day. The patients were followed up once a month, and if there was any eye discomfort during wearing, they were immediately consulted. 1.2 Observation indicators (1) The diopter, axial length and corneal curvature of the three groups were compared before and after wearing the lens for half a year, 1 year, 1.5 years and 2 years, so as to analyze the growth rate of the diopter, axial length and the change of corneal curvature of the three groups. (2) The axial length growth rate of the three groups was compared after wearing the ok lens for half a year, so as to analyze the myopia prevention and control effect of OK lens fitting in different periods. (3) The diopter, the growth rate of axial length and the change of corneal curvature before and after wearing the OK lens were compared among the three groups, so as to analyze whether there was any difference in the prevention and control effects of different types of myopia. 1.4 Statistical methods The data were analyzed by SPSS23.0 software. The measurement data in accordance with normal distribution were compared by t test and expressed as . Pearson correlation analysis was used to analyze the correlation between corneal curvature and axial length, uncorrected visual acuity,༈ P < 0.05༉ were considered statistically significant. 2 Results 2.1 The ocular indexes of the three groups before and after wearing glasses were compared The axial length and diopter of the three groups were improved, but the corneal curvature of the three groups showed a downward trend. By comparing the diopter, corneal curvature and axial length before and after wearing the orthokeratology, the diopter, corneal curvature and axial length after wearing the orthokeratology were significantly better than those before wearing the orthokeratology, and the data were statistically significant (P < 0.05). See Table 1 . Table 1 Comparison of ocular indexes before and after wearing glasses in the three groups( ) Groups Time diopter(DS) Curvature of cornea(D) Axial length of eye(mm) Axial group(n = 58 case) Before wearing glasses -3.00 ± 0.56 41.82 ± 0.79 24.30 ± 0.97 Six months after wearing glasses -3.58 ± 0.96 39.74 ± 0.68 24.50 ± 0.94 1 year after wearing glasses -3.79 ± 1.02 39.51 ± 0.55 24.65 ± 0.95 1.5 years after wearing glasses -4.05 ± 1.67 39.48 ± 0.57 24.83 ± 0.88 2 years after wearing glasses -4.12 ± 1.58 38.17 ± 0.59 25.01 ± 0.94 The curvature group(n = 55 case) Before wearing glasses -3.04 ± 0.64 43.69 ± 1.57 24.58 ± 0.53 Six months after wearing glasses -3.57 ± 0.89 43.50 ± 1.28 24.67 ± 0.49 1 year after wearing glasses -3.68 ± 1.02 43.41 ± 1.40 24.73 ± 0.52 1.5 years after wearing glasses -3.97 ± 1.53 43.02 ± 1.29 24.98 ± 0.82 2 years after wearing glasses -4.01 ± 1.30 42.87 ± 1.08 24.12 ± 0.57 Mixed group(n = 65 case) Before wearing glasses -3.00 ± 0.59 43.82 ± 1.79 24.52 ± 0.55 Six months after wearing glasses -3.58 ± 0.90 39.74 ± 1.68 24.75 ± 0.72 1 year after wearing glasses -4.05 ± 1.03 39.51 ± 1.55 25.18 ± 0.87 1.5 years after wearing glasses -3.88 ± 1.51 38.43 ± 1.26 25.16 ± 0.29 2 years after wearing glasses -3.50 ± 1.32 38.14 ± 1.32 25.38 ± 0.67 2.2 The axial growth rate of the three groups was compared after wearing glasses for half a year By comparing the axial growth rate of the three groups of patients in the half-year cycle after wearing glasses, it was found that the axial growth rate of the patients in each half-year cycle would decrease significantly, and the increase of axial length also showed a downward trend. There was no significant difference in the increase of axial length among the three groups of patients in half a year, 1 year, 1.5 years, and 2 years after wearing glasses (F = 10.20, P > 0.05). P > 0.05). See Table 2 . Table 2 Comparison of the axial growth rate of the three groups in the half-year period after wearing the lens( ,mm) Groups Time Axial growth rate Axial elongation Axial group(n = 58 case) Before wearing glasses 0.31 ± 0.19 (0.2–0.8) Six months after wearing glasses 0.30 ± 0.18 (0.3–0.9) 1 year after wearing glasses 0.27 ± 0.12 (0.2–0.7) 1.5 years after wearing glasses 0.28 ± 0.11 (0.19–0.45) 2 years after wearing glasses 0.27 ± 0.09 (0.1–0.5) The curvature group (n = 55 case) Before wearing glasses 0.14 ± 0.12 (-0.1-0.56) Six months after wearing glasses 0.15 ± 0.13 (-0.4-0.56) 1 year after wearing glasses 0.14 ± 0.12 (-0.03-0.5) 1.5 years after wearing glasses 0.15 ± 0.11 (-0.39-0.55) 2 years after wearing glasses 0.14 ± 0.10 (-0.1-0.51) Mixed group(n = 65 case) Before wearing glasses 0.26 ± 0.11 (0.1–0.5) Six months after wearing glasses 0.25 ± 0.18 (0.2–0.9) 1 year after wearing glasses 0.25 ± 0.12 (0.2–0.5) 1.5 years after wearing glasses 0.24 ± 0.11 (0.12–0.55) 2 years after wearing glasses 0.23 ± 0.27 (0.1–0.12) 2.3 The changes of related indicators before and after wearing glasses were compared among the three groups By comparing the changes of the relevant indicators before and after wearing the contact lens, it was found that after wearing the contact lens, the corneal curvature of all the patients in this study decreased, and there was a significant difference in the corneal curvature between the axial group and the curvature group (P< 0.05). At the same time, the axial elongation of the axial group was significantly higher than that of the curved group and the mixed group, and the difference was statistically significant (P< 0.05). See Table 3 . Table 3 Comparison of the changes of relevant indicators before and after wearing glasses in the three groups( ) Groups Number of cases Changes in corneal curvature(D) Baseline diopter(DS) Baseline axial length(l/mm) Axial elongation(l/mm) Axial group 58 40.21 ± 0.74 -2.81 ± 0.34 24.52 ± 0.42 0.31 ± 0.14 The curvature group 55 44.98 ± 1.53 -3.79 ± 0.27 24.61 ± 0.53 0.18 ± 0.16 Mixed group 65 42.54 ± 1.35 -0.89 ± 0.13 24.49 ± 0.56 0.27 ± 0.15 3. Discussion In recent years, the prevalence of myopia in children and adolescents in China has continued to increase, and gradually shows a younger age trend. Early onset of myopia will not only prolong the course of myopia, but also increase the risk of high myopia. The causes of myopia are complex and closely related to genetic, environmental and other factors [ 13 ]. It is clinically believed that early detection and early intervention of myopia in children should be carried out. In addition to conventional behavioral intervention, outdoor activities, environmental and dietary intervention, reasonable and scientific treatment is also needed [ 14 ]. At present, optical correction plays an important role in the prevention and control of myopia, including wearing glasses and orthokeratology lenses. Although wearing glasses is the mainstream treatment method at present, many studies have recognized that orthokeratology lenses have better therapeutic effects than wearing glasses. Orthokeratology lens (ok lens) is a rigid gas-permeable contact lens with an inverse geometric design. It can reshape the cornea by programmed shaping, flattening the central surface of the anterior cornea and making the peripheral surface steep. The principle of controlling myopia progression is as follows: first, peripheral retinal defocus. ok lenses can shape the cornea to produce a relatively hyperopic refractive state in the central area of the cornea and a relatively myopic refractive state in the peripheral area [ 15 ]. Second, higher order aberrations. Higher-order aberrations provide optical signals for the human body to regulate eye growth and refractive development. ok lens can reduce axial growth, change corneal spherical aberration and coma aberration, and increase higher-order aberrations through asymmetric corneal shape. Third, human eye accommodation. Most myopic children have abnormal accommodation function, low reaction ability and narrow accommodation range, which in turn affect vision and visual function [ 16 ]. ok lens can delay the progression of myopia by changing the corneal morphology, increasing the amplitude and response of accommodation, and reducing the accommodation lag. Fourth, biomechanical effects. ok lens is an inverse corneal shape, which can compress the central cornea through the base arc area of the lens, thereby changing corneal curvature and correcting visual acuity [ 17 ]. Bian Silin et al. [ 18 ] reported that after 1 year of optical treatment, compared with glasses, children wearing orthokeratology lenses had significantly lower axial length growth and thinner central corneal thickness, without affecting anterior chamber depth. The results of this study showed that after comparing the eye indexes of the three groups before and after wearing the lenses, it was found that the AL and diopter levels of the three groups showed an increasing trend from before wearing the lenses to 2 years after wearing the lenses, but the corneal curvature of the three groups showed a decreasing trend. The corneal curvature of the curvature group was significantly higher than that of the axial group and the mixed group (P< 0.05), but the refraction and axial length in the curvature group were significantly lower than those in the axial group and the mixed group (P< 0.05). The study showed that the surface OK lens has a good control effect on the degree of myopia in children, and the growth of the axial length can be effectively controlled after wearing the OK lens. This is mainly due to the effective mechanical compression effect of the lens, and the children's eyelids, eyeballs and the whole glasses carry out corresponding activities in daily life. Can play an effective relative movement behavior, the mutual movement between the lens and the eye, will make the child's whole cornea loose phenomenon, which will make the child's myopia show a flattening effect; At the same time, there will be some tear film between the lens and the cornea. This tear film can play the role of hydraulic pressure to balance the eyelid and the lens of myopia patients, which can make the shape of the corneal surface of myopia patients change significantly. In addition, the ok lens uses specially designed rigid breathable contact lenses to adjust the focus of light by changing the shape of the cornea, which can make the peripheral cornea steep and reduce the relative peripheral hyperopic defocus, thus slowing the growth rate of the axial length [ 19 ]. Lyu Yanyun et al. [ 20 ] reported that wearing orthokeratology lenses helped to delay axial elongation. The reasons for the lower axial length in the steep group may be: first, the change of corneal morphology. ok lens treatment can change the morphology of the cornea by squeezing the cornea moderately. In patients with steep corneal curvature, the extrusion effect of the ok lens may cause the curvature of the cornea to become flatter, resulting in a reduction in axial length. Second, optical accommodation: ok lenses correct myopia by changing the shape of the cornea to adjust the focus of light. For patients with steep corneal curvature, the position of the pericentrum (focus) of the cornea may move forward. With the ok lens treatment, the position of the pericardium can be moved back, making the measurement of the axial length relatively small. Third, visual stimulus modulation. ok lens treatment was worn at night, while no lenses were worn during the day. This periodic wearing mode can provide different visual stimuli and may have some modulatory effect on the visual system. This accommodative effect may affect the measurement of axial length [ 21 – 22 ]. The growth rate of AL was significantly decreased in every half year period, and the increase of AL also showed a downward trend. There was no significant difference in the increase of AL among the three groups in half a year, 1 year, 1.5 years and 2 years after wearing glasses (F = 10.20, P > 0.05). On the surface of the study, the axial growth rate of the three groups of patients is consistent, which indicates that in the control of myopia, the control effect of each group is not significantly different. At the same time, the study showed that the corneal curvature of all patients in this study decreased after wearing the contact lens, and there was a significant difference in the corneal curvature between the axial group and the curvature group (P< 0.05). At the same time, the axial elongation of the three groups was significantly higher than that of the flexure group and the mixed group (P< 0.05). It is suggested that the acting orthokeratology lens can effectively control the axial elongation of children with myopia, and this control effect is more obvious for the curvature group and the mixed group. Yin Y et al. [ 24 ] reported that corneal curvature was significantly reduced after wearing ok lenses. The reason is that the ok lens can be based on the corneal remodeling effect. The slight pressure applied to the cornea through the lens will cause the corneal epithelial cells to rearrange, which will change the shape of the cornea and then affect the corneal curvature radius. However, this study shows that age is the main factor for the treatment effect of wearing ok lenses, while corneal curvature is not the main factor for the treatment effect of wearing ok lenses, which is controversial with the results of this study. Xie Jing et al. [26] reported that adolescents with longer axial length, older age, and greater corneal curvature had better effects on controlling myopia progression. The reason is that after wearing the ok lens at night, a flat area is pressed out in the central area of the cornea, which can not only correct myopia, but also make the peripheral imaging more suitable for the retina, and even produce "peripheral myopic defocus". The higher the corneal curvature, the more corneas can be flattened in the center of the ok lens, the greater the amount of peripheral defocus will be produced, and the better the control effect will be. In addition, the visual accommodation mechanism may automatically adjust the axial length to accommodate the changes in corneal curvature. However, for initial long axial myopia, OK lens is relatively difficult to suppress, so it is necessary to monitor the progress of myopia more strictly. If necessary, combined methods can be used to prevent and control the initial long axial myopia in time according to the severity of the patient's long axial myopia, and according to the specific conditions of the patient's long axial myopia, It is appropriate to consider whether myopia control with defocus techniques or low concentration atropine eyedrops can be performed on the patient at an earlier pre-myopic stage. In conclusion, 1. The effect of ok lens on myopia prevention and control is closely related to the type of initial myopia; Compared with initial myopia children with long axial length, OK lens is more effective in controlling axial length growth in initial myopia children with high curvature, but has less effect on uncorrected visual acuity. (2) There may be natural differences in axial growth rate between the two types of initial myopia, and the benefits of OK lens on its prevention and control need to be further studied and compared. Declarations Author Contribution No conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed. References Lu Fan, Chen Yiya. 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The disease is also a serious public health problem, with a high prevalence rate, about 3.4%-42.2% in European and American countries, and about 13.8%-70.9% in China [1]. Among them, children have a high incidence of myopia. Once myopia occurs, it will show a progressive trend and is irreversible, and the development rate can be slowed down until early adulthood [2]. Without timely intervention, it will progress to high myopia, which may induce a series of serious eye complications such as retinal detachment and glaucoma, and have a serious impact on the quality of life of patients. Therefore, it is clinically believed that myopia prevention and control should be paid attention to [3]. Among them, ok lenses, also known as orthokeratology lenses, can effectively delay the progression of myopia and control the growth of axial length [4-5]. Although many studies have confirmed the effect of ok lens on myopia control, the treatment effect of this technique is affected by many factors. Among them, corneal curvature is an important eyeball biological parameter, and abnormal steepening of corneal curvature is a common cause of myopia [6-8]. Studies have reported that corneal curvature may be an important factor for the therapeutic effect of ok lens [9]. Another study [10] reported that corneal curvature was not an independent influencing factor for the treatment effect of ok lens. At present, there is still some controversy about whether corneal curvature will affect the efficacy of ok lens. Based on this, this study will analyze the effect of ok lens on myopia with different corneal curvature, in order to clarify the relationship between corneal curvature and the therapeutic effect of ok lens. The trial is reported as follows:\u003c/p\u003e"},{"header":"1 Materials and Methods","content":"\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e \u003ch2\u003e1.1 General Information\u003c/h2\u003e \u003cp\u003e A total of 178 myopic children admitted to our hospital from April 2019 to July 2021 were selected and grouped according to different corneal curvature at baseline. The children were divided into three groups: axial group (corneal curvature\u0026thinsp;\u0026le;\u0026thinsp;41.5D, n\u0026thinsp;=\u0026thinsp;58), curvature group (corneal curvature\u0026thinsp;\u0026ge;\u0026thinsp;44D, n\u0026thinsp;=\u0026thinsp;58), and axial group (corneal curvature\u0026thinsp;\u0026ge;\u0026thinsp;44D, n\u0026thinsp;=\u0026thinsp;58). n\u0026thinsp;=\u0026thinsp;55) and mixed group (41.5D\u0026thinsp;\u0026le;\u0026thinsp;corneal curvature\u0026thinsp;\u0026le;\u0026thinsp;44D, n\u0026thinsp;=\u0026thinsp;65). Among them, there were 58 patients in the axial group, including 28 males and 30 females, aged 6\u0026ndash;15 years, with an average age of 10.24\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27 years. There were 55 patients in the curved group, including 30 males and 25 females, aged from 6 to 15 years, with an average age of 10.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25 years. There were 65 patients in the mixed group, including 31 males and 34 females, aged 6\u0026ndash;15 years, with an average age of 10.29\u0026thinsp;\u0026plusmn;\u0026thinsp;1.30 years. There were no significant differences in baseline data (gender and age) among the three groups (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003eInclusion criteria: (1) school-age children aged 6\u0026ndash;15 years who met the diagnostic criteria for myopia [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]; (2) no previous history of wearing ok lenses; (3) The informed consent was signed by the family members of the children.\u003c/p\u003e \u003cp\u003eExclusion criteria: (1) presence of dry eye, acute ocular inflammation, other ocular organic diseases or contraindications to ok lens; (2) the presence of neurological or systemic diseases affecting refractive development; (3) pathological myopia.\u003c/p\u003e \u003cp\u003e \u003cb\u003eMethods\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAll children were treated with ok lens, the operation was as follows: wearing the Euclidean OK lens, the inner surface of the lens was an inverse geometric four-arc design (Boston Equalens high oxygen permeability material), the diameter/central thickness was 10.6 mm/ 0.2 mm. The clinicians determined the parameters according to the patient's specific eyeball biological characteristics (corneal curvature, diopter, etc.), and informed the children and their families to wear ok lenses correctly, and professional technicians guided the maintenance of the lenses. Continuous night wear, wear 8\u0026ndash;10 hours per night, continuous wear 12m, no need to wear any glasses during the day. The patients were followed up once a month, and if there was any eye discomfort during wearing, they were immediately consulted.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e1.2 Observation indicators\u003c/h2\u003e \u003cp\u003e(1) The diopter, axial length and corneal curvature of the three groups were compared before and after wearing the lens for half a year, 1 year, 1.5 years and 2 years, so as to analyze the growth rate of the diopter, axial length and the change of corneal curvature of the three groups.\u003c/p\u003e \u003cp\u003e(2) The axial length growth rate of the three groups was compared after wearing the ok lens for half a year, so as to analyze the myopia prevention and control effect of OK lens fitting in different periods.\u003c/p\u003e \u003cp\u003e(3) The diopter, the growth rate of axial length and the change of corneal curvature before and after wearing the OK lens were compared among the three groups, so as to analyze whether there was any difference in the prevention and control effects of different types of myopia.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e1.4 Statistical methods\u003c/h2\u003e \u003cp\u003eThe data were analyzed by SPSS23.0 software. The measurement data in accordance with normal distribution were compared by t test and expressed as \u003cimg src=\"data:image/png;base64,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\"\u003e. Pearson correlation analysis was used to analyze the correlation between corneal curvature and axial length, uncorrected visual acuity,༈\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05༉ were considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"2 Results","content":"\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.1 The ocular indexes of the three groups before and after wearing glasses were compared\u003c/h2\u003e \u003cp\u003eThe axial length and diopter of the three groups were improved, but the corneal curvature of the three groups showed a downward trend. By comparing the diopter, corneal curvature and axial length before and after wearing the orthokeratology, the diopter, corneal curvature and axial length after wearing the orthokeratology were significantly better than those before wearing the orthokeratology, and the data were statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). See Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of ocular indexes before and after wearing glasses in the three groups(\u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroups\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTime\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ediopter(DS)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCurvature of cornea(D)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAxial length of eye(mm)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eAxial group(n\u0026thinsp;=\u0026thinsp;58 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e41.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e39.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.94\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.79\u0026thinsp;\u0026plusmn;\u0026thinsp;1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e39.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.95\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-4.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e39.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.83\u0026thinsp;\u0026plusmn;\u0026thinsp;0.88\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-4.12\u0026thinsp;\u0026plusmn;\u0026thinsp;1.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e38.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e25.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.94\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eThe curvature group(n\u0026thinsp;=\u0026thinsp;55 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.04\u0026thinsp;\u0026plusmn;\u0026thinsp;0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e43.69\u0026thinsp;\u0026plusmn;\u0026thinsp;1.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e43.50\u0026thinsp;\u0026plusmn;\u0026thinsp;1.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.49\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.68\u0026thinsp;\u0026plusmn;\u0026thinsp;1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e43.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.97\u0026thinsp;\u0026plusmn;\u0026thinsp;1.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e43.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.98\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-4.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e42.87\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.57\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eMixed group(n\u0026thinsp;=\u0026thinsp;65 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e43.82\u0026thinsp;\u0026plusmn;\u0026thinsp;1.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e39.74\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-4.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e39.51\u0026thinsp;\u0026plusmn;\u0026thinsp;1.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e25.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.87\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e38.43\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e25.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e-3.50\u0026thinsp;\u0026plusmn;\u0026thinsp;1.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e38.14\u0026thinsp;\u0026plusmn;\u0026thinsp;1.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e25.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e2.2 The axial growth rate of the three groups was compared after wearing glasses for half a year\u003c/p\u003e \u003cp\u003eBy comparing the axial growth rate of the three groups of patients in the half-year cycle after wearing glasses, it was found that the axial growth rate of the patients in each half-year cycle would decrease significantly, and the increase of axial length also showed a downward trend. There was no significant difference in the increase of axial length among the three groups of patients in half a year, 1 year, 1.5 years, and 2 years after wearing glasses (F\u0026thinsp;=\u0026thinsp;10.20, P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). See Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of the axial growth rate of the three groups in the half-year period after wearing the lens(\u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e,mm)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroups\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTime\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAxial growth rate\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAxial elongation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eAxial group(n\u0026thinsp;=\u0026thinsp;58 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.2\u0026ndash;0.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.3\u0026ndash;0.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.2\u0026ndash;0.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.19\u0026ndash;0.45)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.1\u0026ndash;0.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eThe curvature group\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;55 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(-0.1-0.56)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(-0.4-0.56)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(-0.03-0.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(-0.39-0.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(-0.1-0.51)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eMixed group(n\u0026thinsp;=\u0026thinsp;65 case)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBefore wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.1\u0026ndash;0.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSix months after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.2\u0026ndash;0.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 year after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.2\u0026ndash;0.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.12\u0026ndash;0.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 years after wearing glasses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.23\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e(0.1\u0026ndash;0.12)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e2.3 The changes of related indicators before and after wearing glasses were compared among the three groups\u003c/p\u003e \u003cp\u003eBy comparing the changes of the relevant indicators before and after wearing the contact lens, it was found that after wearing the contact lens, the corneal curvature of all the patients in this study decreased, and there was a significant difference in the corneal curvature between the axial group and the curvature group (P\u0026amp;lt; 0.05). At the same time, the axial elongation of the axial group was significantly higher than that of the curved group and the mixed group, and the difference was statistically significant (P\u0026amp;lt; 0.05). See Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of the changes of relevant indicators before and after wearing glasses in the three groups(\u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroups\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of cases\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChanges in corneal curvature(D)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBaseline diopter(DS)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBaseline axial length(l/mm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAxial elongation(l/mm)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAxial group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e40.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-2.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e0.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe curvature group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e44.98\u0026thinsp;\u0026plusmn;\u0026thinsp;1.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-3.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e0.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMixed group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e42.54\u0026thinsp;\u0026plusmn;\u0026thinsp;1.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.89\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e24.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e0.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"3. Discussion","content":"\u003cp\u003eIn recent years, the prevalence of myopia in children and adolescents in China has continued to increase, and gradually shows a younger age trend. Early onset of myopia will not only prolong the course of myopia, but also increase the risk of high myopia. The causes of myopia are complex and closely related to genetic, environmental and other factors [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. It is clinically believed that early detection and early intervention of myopia in children should be carried out. In addition to conventional behavioral intervention, outdoor activities, environmental and dietary intervention, reasonable and scientific treatment is also needed [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. At present, optical correction plays an important role in the prevention and control of myopia, including wearing glasses and orthokeratology lenses. Although wearing glasses is the mainstream treatment method at present, many studies have recognized that orthokeratology lenses have better therapeutic effects than wearing glasses.\u003c/p\u003e \u003cp\u003eOrthokeratology lens (ok lens) is a rigid gas-permeable contact lens with an inverse geometric design. It can reshape the cornea by programmed shaping, flattening the central surface of the anterior cornea and making the peripheral surface steep. The principle of controlling myopia progression is as follows: first, peripheral retinal defocus. ok lenses can shape the cornea to produce a relatively hyperopic refractive state in the central area of the cornea and a relatively myopic refractive state in the peripheral area [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Second, higher order aberrations. Higher-order aberrations provide optical signals for the human body to regulate eye growth and refractive development. ok lens can reduce axial growth, change corneal spherical aberration and coma aberration, and increase higher-order aberrations through asymmetric corneal shape. Third, human eye accommodation. Most myopic children have abnormal accommodation function, low reaction ability and narrow accommodation range, which in turn affect vision and visual function [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. ok lens can delay the progression of myopia by changing the corneal morphology, increasing the amplitude and response of accommodation, and reducing the accommodation lag. Fourth, biomechanical effects. ok lens is an inverse corneal shape, which can compress the central cornea through the base arc area of the lens, thereby changing corneal curvature and correcting visual acuity [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Bian Silin et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] reported that after 1 year of optical treatment, compared with glasses, children wearing orthokeratology lenses had significantly lower axial length growth and thinner central corneal thickness, without affecting anterior chamber depth.\u003c/p\u003e \u003cp\u003eThe results of this study showed that after comparing the eye indexes of the three groups before and after wearing the lenses, it was found that the AL and diopter levels of the three groups showed an increasing trend from before wearing the lenses to 2 years after wearing the lenses, but the corneal curvature of the three groups showed a decreasing trend. The corneal curvature of the curvature group was significantly higher than that of the axial group and the mixed group (P\u0026amp;lt; 0.05), but the refraction and axial length in the curvature group were significantly lower than those in the axial group and the mixed group (P\u0026amp;lt; 0.05). The study showed that the surface OK lens has a good control effect on the degree of myopia in children, and the growth of the axial length can be effectively controlled after wearing the OK lens. This is mainly due to the effective mechanical compression effect of the lens, and the children's eyelids, eyeballs and the whole glasses carry out corresponding activities in daily life. Can play an effective relative movement behavior, the mutual movement between the lens and the eye, will make the child's whole cornea loose phenomenon, which will make the child's myopia show a flattening effect; At the same time, there will be some tear film between the lens and the cornea. This tear film can play the role of hydraulic pressure to balance the eyelid and the lens of myopia patients, which can make the shape of the corneal surface of myopia patients change significantly. In addition, the ok lens uses specially designed rigid breathable contact lenses to adjust the focus of light by changing the shape of the cornea, which can make the peripheral cornea steep and reduce the relative peripheral hyperopic defocus, thus slowing the growth rate of the axial length [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Lyu Yanyun et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] reported that wearing orthokeratology lenses helped to delay axial elongation. The reasons for the lower axial length in the steep group may be: first, the change of corneal morphology. ok lens treatment can change the morphology of the cornea by squeezing the cornea moderately. In patients with steep corneal curvature, the extrusion effect of the ok lens may cause the curvature of the cornea to become flatter, resulting in a reduction in axial length. Second, optical accommodation: ok lenses correct myopia by changing the shape of the cornea to adjust the focus of light. For patients with steep corneal curvature, the position of the pericentrum (focus) of the cornea may move forward. With the ok lens treatment, the position of the pericardium can be moved back, making the measurement of the axial length relatively small. Third, visual stimulus modulation. ok lens treatment was worn at night, while no lenses were worn during the day. This periodic wearing mode can provide different visual stimuli and may have some modulatory effect on the visual system. This accommodative effect may affect the measurement of axial length [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. The growth rate of AL was significantly decreased in every half year period, and the increase of AL also showed a downward trend. There was no significant difference in the increase of AL among the three groups in half a year, 1 year, 1.5 years and 2 years after wearing glasses (F\u0026thinsp;=\u0026thinsp;10.20, P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). On the surface of the study, the axial growth rate of the three groups of patients is consistent, which indicates that in the control of myopia, the control effect of each group is not significantly different. At the same time, the study showed that the corneal curvature of all patients in this study decreased after wearing the contact lens, and there was a significant difference in the corneal curvature between the axial group and the curvature group (P\u0026amp;lt; 0.05). At the same time, the axial elongation of the three groups was significantly higher than that of the flexure group and the mixed group (P\u0026amp;lt; 0.05). It is suggested that the acting orthokeratology lens can effectively control the axial elongation of children with myopia, and this control effect is more obvious for the curvature group and the mixed group. Yin Y et al. [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] reported that corneal curvature was significantly reduced after wearing ok lenses. The reason is that the ok lens can be based on the corneal remodeling effect. The slight pressure applied to the cornea through the lens will cause the corneal epithelial cells to rearrange, which will change the shape of the cornea and then affect the corneal curvature radius. However, this study shows that age is the main factor for the treatment effect of wearing ok lenses, while corneal curvature is not the main factor for the treatment effect of wearing ok lenses, which is controversial with the results of this study. Xie Jing et al. [26] reported that adolescents with longer axial length, older age, and greater corneal curvature had better effects on controlling myopia progression. The reason is that after wearing the ok lens at night, a flat area is pressed out in the central area of the cornea, which can not only correct myopia, but also make the peripheral imaging more suitable for the retina, and even produce \"peripheral myopic defocus\". The higher the corneal curvature, the more corneas can be flattened in the center of the ok lens, the greater the amount of peripheral defocus will be produced, and the better the control effect will be. In addition, the visual accommodation mechanism may automatically adjust the axial length to accommodate the changes in corneal curvature. However, for initial long axial myopia, OK lens is relatively difficult to suppress, so it is necessary to monitor the progress of myopia more strictly. If necessary, combined methods can be used to prevent and control the initial long axial myopia in time according to the severity of the patient's long axial myopia, and according to the specific conditions of the patient's long axial myopia, It is appropriate to consider whether myopia control with defocus techniques or low concentration atropine eyedrops can be performed on the patient at an earlier pre-myopic stage.\u003c/p\u003e \u003cp\u003eIn conclusion, 1. The effect of ok lens on myopia prevention and control is closely related to the type of initial myopia; Compared with initial myopia children with long axial length, OK lens is more effective in controlling axial length growth in initial myopia children with high curvature, but has less effect on uncorrected visual acuity. (2) There may be natural differences in axial growth rate between the two types of initial myopia, and the benefits of OK lens on its prevention and control need to be further studied and compared.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eNo conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLu Fan, Chen Yiya. Iteration and significance of epidemiological studies on myopia [J]. Chin J Ophthalmol,2021,57(4):245\u0026ndash;250.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQi Ziyi, Chen Jun, He Xiangui. Epidemiology of high myopia in children and adolescents in China [J]. Chin J Ophthalmol,2023,59(2):138\u0026ndash;145.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWei Ruihua, Zhang Hongmei, Liu Shengxin, et al. To strengthen the scientific prevention and control of myopia in children and adolescents in China [J]. Progress in Ophthalmology,2023,43(1):1\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXU Jingjing, Wang Shuai, Chen Yunyun, et al. The effect of orthokeratology lens on the refractive state of the contralateral eye in monocular myopic children [J]. Chinese Journal of Optometry and Vision Science, 222,24(10):760\u0026ndash;766.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen Z, Zhang Z, Xue F, et al. The relationship between myopia progression and axial elongation in children wearing orthokeratology contact [J]. Cont Lens Anterior Eye,2023,46(1):101517.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShen Jie, Sun Huihua. The change of axial length and corneal curvature in children with simple myopia [J]. Journal of Shanghai Second Medical University,2003,23(6):533\u0026ndash;534,537.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang Hong, Zhao Keke, Qu Jifang, et al. The accuracy of axial length to corneal radius ratio in the qualitative assessment of myopia in adolescents and children [J]. Chin J Ophthalmol and Vision Science,2016,18(2):108\u0026ndash;110.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYang Yin, Yang Zhuoxi, Du Nian, et al. Analysis of ocular biological parameters and characteristics of myopic children in Sichuan Province [J]. Journal of Sichuan University (Medical Edition),2019,50(4):577\u0026ndash;579.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXie Xiangyong, He Bihua, Wei Lijiao. Influencing factors of orthokeratology lens fitting effect [J]. Int J Ophthalmol,2013,13(1):199\u0026ndash;200.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi M H, Zhang J, Li C, et al. Influencing factors of orthokeratology for myopia control in adolescents [J]. Chinese People's Armed Police Medicine,2023,34(3):202\u0026ndash;205.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChinese Society of Optometry, Chinese Ophthalmologist Association, Chinese Medical Doctor Association. Chinese Journal of Optometry and Vision Science,2019,21(1):1\u0026ndash;4. (in Chinese)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePublic Health Ophthalmology Branch of Chinese Preventive Medicine Association. Chinese expert consensus on the reference intervals of ocular hyperopia reserve, axial length, corneal curvature and related genetic factors in school-age children (2022) [J]. Chin J Ophthalmol, 2021,58(2):96\u0026ndash;102.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBremond-Gignac D. Myopie de l 'Enfant [Myopia in children]. Med Sci (Paris),2020,36(8\u0026ndash;9):763\u0026ndash;768.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHua Lei, Liu Hu, Zhang Zhiqiang. Prevention and control of myopia in school-age children [J]. Chinese Journal of Optometry and Vision Science,2020,22(7):555\u0026ndash;560.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTang SM, Zhang XJ, Yu M, et al. Association of Corneal Biomechanics Properties with Myopia in a Child and a Parent Cohort: Diagnosis (Basel), 2021,11(12):2357. (in Chinese)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWU Jinfang, Zhang Xin-yu, BAO Fang-jun, et al. The mechanism of orthokeratology in myopia control [J]. Chinese Journal of Strabismus and Pediatric Ophthalmology, 2021,30(4):41\u0026ndash;42, posterior insertion 8-posterior insertion 10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu Han, Xu Jiangtao. Research progress on the safety of orthokeratology lenses and the influencing factors of visual quality [J]. Chinese Journal of Strabismus and Child Ophthalmology,2023,31(1):42\u0026ndash;43, SP 12-SP 13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSilin Bian, Hua Liu, Jiang Lin. A randomized controlled study on the clinical effect of myopia children wearing orthokeratology lenses and spectacles for one year [J]. Chin J Lab Ophthalmol,2020,38(2):121\u0026ndash;127.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYuan S, Zhang S, Jiang Y, et al. Effect of short-term orthokeratology lens or ordinary frame glasses wear on corneal thickness, corneal endothelial cells and vision correction in adolescents with low to moderate myopia[J]. BMC Ophthalmol,2019, 19 (1) : 242.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu Yanyun, WU Jingjing, Guo Wei, et al. Effect of orthokeratology lens on the prevention and treatment of myopic anisometropia in children [J]. Chin J Preventive Med,2021,55(4):471\u0026ndash;477.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHan Chengcheng, Zhang Zhiping, MA Zhuolin, et al. Effect of preserving physiological accommodation tension on myopia control in children and adolescents [J]. Chinese Journal of Strabismus \u0026amp; Pediatric Ophthalmology,2023,31(1):25\u0026ndash;28.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTong Zhenzhen, Li Yi, Feng Jianmei, et al. Short-term efficacy of orthokeratology in the treatment of myopia in school-age children [J]. Chinese J Practical Ophthalmol,2017,35(5):472\u0026ndash;475.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFu A C, Xie H B, LV Y, et al. Changes of central and paracentral corneal curvature after wearing orthokeratology lens in juvenile myopia at night [J]. Chinese Journal of Practical Ophthalmol,2015,33(1):33\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYin Y, Zhao Y, Wu X, et al. One-year effect of wearing orthokeratology lenses on the visual quality of juvenile myopia: a retrospective study[J]. PeerJ,2019,7:e6998.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXie Jing, Feng Yunhong, Jin Shoumei, et al. Regression analysis of the influence factors of orthokeratology on the development of myopia in adolescents [J]. International J Ophthalmol,2015(5):872\u0026ndash;874.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Children, Myopia, Corneal curvature, OK mirror, Eye axis length","lastPublishedDoi":"10.21203/rs.3.rs-4247883/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4247883/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eObjective: To explore the effect of OK lens on myopia control in children with different corneal curvature.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMethod: A total of 178 myopic children admitted to our hospital from April 2019 to July 2021 were selected and grouped according to the baseline (at enrollment), and the children were divided into three groups, namely axial group (corneal curvature 41.5D, n=58), curvature group (corneal curvature 44D, n=55), and mixed group (41.5D corneal curvature 44D, n=65). All the children were treated with ok lens; comparing the growth rate of refraction, axial length, corneal curvature and axial axis respectively, and analyzing the prevention and control effect of myopia in different cycles and whether the prevention and control effect of different types of myopia were different.\u003c/p\u003e\n\u003cp\u003eResult: The axis and refraction of the three groups improved within 2 years after wear, but the corneal curvature in the three groups showed a decreasing trend; After comparing the refraction, corneal curvature and axial length after wear, the refraction, corneal curvature and axial length were significantly better than those before wear (P \u0026lt;0.05). The growth rate of the axial axis of patients in the half-annual cycle decreased significantly, and the increase of axial axis also showed a decreasing trend. The difference between the increase of axial axis in the half year, 1 year, 1.5 years and 2 years after wearing the mirror was not significant (P\u0026gt; 0.05). In addition, corneal curvature in all patients in the study decreased after lens wear, and there was significant differences in corneal curvature between the axial and curvature groups (P \u0026lt;0.05). At the same time, the axial growth was significantly higher than that in the curvature and mixed groups (P \u0026lt;0.05).\u003c/p\u003e\n\u003cp\u003eConclusion: There is a close correlation between corneal curvature and the effectiveness of OK lens treatment. Compared to children with flat corneal curvature, OK lens has a more ideal effect on controlling the axial length of the eyes in children with steep corneal curvature, but has less impact on naked eye vision.\u003c/p\u003e","manuscriptTitle":"Study on the myopia control effect of OK lens on children with different corneal curvature","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-16 19:04:40","doi":"10.21203/rs.3.rs-4247883/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8ca89d07-29dd-4c7f-ac39-c3cf7dab816c","owner":[],"postedDate":"April 16th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-06-22T22:38:20+00:00","versionOfRecord":[],"versionCreatedAt":"2024-04-16 19:04:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4247883","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4247883","identity":"rs-4247883","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}