ABSTRACT
Objective:To observe and analyze the changes of macular retinal thickness and related factors in children with occult myopia.Methods:A prospective longitudinal control study. From February 2021 to February 2022, 120 eyes of 60 children who first visited Department of Ophthalmology of The Affiliated Hospital of Chengde Medical College without any corresponding myopia correction treatment were included in the study. There were 32 males (64 eyes) and 28 females (56 eyes), with the age of 4-6 years. Visual acuity, medical optometry, corneal topography, spectral-domain optical coherence tomography (OCT) and axial length (AL) were measured at the first visit and 3, 6, 9 and 12 months. The children were divided into occult myopia group with 60 eyes of 30 cases and control group with 60 eyes of 30 cases according to visual acuity, equivalent spherical refraction (SE), AL and corneal curvature (CC). The macular fovea retinal thickness was measured by spectral-domain OCT enhanced deep imaging technique. According to the treatment and study of diabetic retinopathy, the retina within the 6 mm of the macular center was divided into three concentric circles with the macular fovea as the center, the central fovea of 1 mm, the inner ring of 1-3 mm and the outer ring of 3-6 mm. In the inner ring and outer ring, the retina was divided into 4 areas, upper and lower, left and right, with a total of 9 regions. The four regions of the inner ring and the outer ring were superior, inferior, nasal and temporal, respectively. The differences of AL, CC, SE, macular retinal thickness and the changes of related factors with time were compared between the occult myopia group and the control group. SE, AL, CC and retinal thickness in different macular regions of the two groups were compared by repeated measurement analysis of variance. In pairwise comparison, the minimum significant difference t test was used in different measurement time points, and the independent sample t test was used between groups at the same measurement time points. Results:At first diagnosis and after diagnosis, there were significant differences in SE ( F=783.710), AL ( F=742.192), macular fovea ( F=330.292), inferior and temporal ( F=158.250, 108.292) side of the outer ring retinal thickness in occult myopia group ( P <0.01). In the control group, there were significant differences in the retinal thickness of SE ( F=1 793.976), AL ( F=457.362), macular fovea ( F=31.029), inferior and temporal ( F=7.405, 77.245) side of the outer ring retinal thickness ( P<0.01). In both groups, with the prolongation of the time after the first diagnosis, the SE gradually increased, the AL gradually lengthened, and the thickness of the macular fovea, inferior and temporal side of the outer ring retinal thickness gradually thinned. Independent sample t test was performed on the data with differences between groups at the same time, and the results showed that at 3, 6, 9 and 12 months after first diagnosis, there were significant differences in SE, AL and CC between the occult myopia group and the control group ( t=-4.801,-11.532, 16.276, -17.145), AL ( t=24.203, 26.353, 27.057, 25.552); CC ( t=-23.362, -25.382, -25.890, -24.350; P<0.01). There were significant differences in macular fovea, inferior and temporal side of the outer ring retinal thickness at 6, 9 and 12 months, macular fovea ( t=-2.596, -2.542, -2.941; P<0.05), outer ring temporal ( t =-2.285, -2.610, -2.506; P<0.05). Conclusion:The SE and AL of the occult myopia group and the control group increase with time, and the former increase more rapidly than the latter; the macular fovea, inferior and temporal side of the outer ring retinal become thinner, and the former become thinner than the latter.
ABSTRACT
Objective:To investigate the effect of astaxanthin on the refractive status and pathological morphology of the guinea pig myopia models induced by concave lens,and to elucidate the improvement effect of astaxanthin on the refractive status of myopia.Methods:A total of 48 healthy guinea pigs were randomly divided into blank control group (n=12) and model group (n=36);the guinea pig myopia models (right eyes) were established with far vision optical method (left eyes were used as control).The guinea pig models were divided into model control group,high of astaxanthin (50 ig · kg-1) group and low dose of astaxanthin (25 ig · kg 1) group.After 2 and 4 weeks treatment,the diopters and the lengths of optic axis of both eyes of each guinea pig in various groups were tested,and at 4 weeks the right eyes of the pigs were removed and the pathomorphology was observed by HE staining.Results:The diopters of the model eyes in model group were lower than those of left eyes used as control (P＜0.05) and those of right eyes in blank control group after 2 and 4 weeks (P＜0.05 or P＜0.01).The length of optic axis of the model eye in model group was increased compared with left eye used as controls and blank control group after 2 weeks (P＜0.05) and especially at 4 weeks (P＜0.01).Compared with model group,the axial oculi and diopters of the guinea pigs in astaxanthin groups were increased (P＜0.05);the pathohistological changes were improved,the collagen fracture was obviously decreased,and the collagen fibers were orderly arranged.Conclusion:Astaxanthin can recover the length of optic axis,diopter and histomorphology of sclera of guinea pig myopia models in some extents.
ABSTRACT
Objective:To investigate the effect of astaxanthin on the refractive status and pathological morphology of the guinea pig myopia models induced by concave lens,and to elucidate the improvement effect of astaxanthin on the refractive status of myopia.Methods:A total of 48 healthy guinea pigs were randomly divided into blank control group (n=12) and model group (n=36);the guinea pig myopia models (right eyes) were established with far vision optical method (left eyes were used as control).The guinea pig models were divided into model control group,high of astaxanthin (50 ig · kg-1) group and low dose of astaxanthin (25 ig · kg 1) group.After 2 and 4 weeks treatment,the diopters and the lengths of optic axis of both eyes of each guinea pig in various groups were tested,and at 4 weeks the right eyes of the pigs were removed and the pathomorphology was observed by HE staining.Results:The diopters of the model eyes in model group were lower than those of left eyes used as control (P＜0.05) and those of right eyes in blank control group after 2 and 4 weeks (P＜0.05 or P＜0.01).The length of optic axis of the model eye in model group was increased compared with left eye used as controls and blank control group after 2 weeks (P＜0.05) and especially at 4 weeks (P＜0.01).Compared with model group,the axial oculi and diopters of the guinea pigs in astaxanthin groups were increased (P＜0.05);the pathohistological changes were improved,the collagen fracture was obviously decreased,and the collagen fibers were orderly arranged.Conclusion:Astaxanthin can recover the length of optic axis,diopter and histomorphology of sclera of guinea pig myopia models in some extents.