Idiopathic macular membrane (iERM) is a fibrocellular membrane that forms on the inner surface of the retina. In its early stages, symptoms of iERM are usually not apparent. However, advanced iERM can cause different degrees of visual impairment and effect the quality of life of patients. Current studies suggest that iERM may be associated with posterior vitreous detachment (PVD), age, sex, race and/or ethnicity, poor lifestyle, refractive error, diabetes, hypercholesterolemia, and cardiovascular disease. The most well-established risk factors for iERM are age and PVD. The pathogenesis of iERM is extremely complex. Various cell types, such as Müller cells, Hyalocytes and myofibroblasts, nerve growth factor, interleukin-6, transforming growth factor β, vascular endothelial growth factor and other cytokines and growth factors, as well as a variety of genes and proteins are directly or indirectly involved in the formation of iERM, however, their exact role remains a mystery. In the future, further studies at the molecular level and gene level are needed to provide greater help for the clinical diagnosis and treatment of iERM.
ObjectiveTo explore the distribution of choroidal thickness and its influence factors in university students.MethodsA cross-sectional study. A total of 896 eyes of 896 college students were included in the study. Among them, there were 350 males (350 eyes) and 546 females (546 eyes). All the eyes were right eyes. The average age was 19.18 ± 1.36 years old. According to the spherical equivalent refraction (SER), the eyes were divided into non-myopia group, low myopia group, moderate myopia group and high myopia group, which were 59, 251, 356 and 230 eyes, respectively. The subfoveal ChT (SFCT) was measured using a swept-frequency source optical coherence tomography scanner. According to the ETDRS, the choroid within 6 mm of the fovea was divided into three concentric circles centered on the fovea of the macula, which were the central area with a diameter of 1 mm, the inner ring area of 1-3 mm and the outer ring area of 3-6 mm. The outer ring area of 3-6 mm has a total of 9 zones. The inner ring and outer ring 4 regions were superior, inferior, nasal and temporal, respectively. The distribution characteristics of ChT in different regions, genders and diopter groups were observed. Bivariate correlation analysis were used to analyze the correlation of ChT and SER, axial length (AL).ResultsThe average SFCT of 896 eyes was 221.28±67.35 μm. The mean SFCT of males and females were 227.20±69.38 and 217.50±65.80 μm, respectively. The difference of SFCT between different genders was statistically significant (t=2.075, P=0.038). Compared with the central region ChT, there was no significant difference in ChT between the outer ring and the outer region (t=0.086, P=0.932). The difference of ChT in other regions was statistically significant (t=-21.973, -5.818, 36.328, -3.065, -18.017, -10.595, 57.007; P＜0.001, ＜0.001, ＜0.001, ＜0.002, ＜0.001, ＜0.001, ＜0.001). In the horizontal direction, ChT gradually thickens from nasal to temporal (F=2 251.558, P＜0.001); in the vertical direction, ChT gradually decreases from superior to the central, but have a little increased from central to inner inferior, then decreased to outer inferior again (F=45.425, P＜0.05). Correlation analysis showed that SFCT was negatively correlated with AL (r=0.478, P＜0.01) and a negative correlation with axial length (r=−0.395, P＜0.01), and positively correlated with SER (r=0.478, P＜0.01). SFCT decreased by 12.29 μm for every in myopic refractive error of 1 D, or by 20.14 μm for every increase in AL of 1 mm.ConclusionsChT is changed by different location. The horizontal direction is gradually thickened from nasal to temporal. The vertical direction is thicker than the center. The inferior inner ring area is thicker than the outer ring area. Gender, SER and AL are the influencing factors of SFCT.
ObjectiveTo investigate the prevalence and risk factors of tessellation fundus (TF) among Tianjin Medical University students with different refractive statuses. MethodsA cross-sectional study. From September to December 2019, 346 students from Tianjin Medical University were randomly selected and underwent slit-lamp examination, non-cycloplegic auto-refraction, subjective refraction, best-corrected visual acuity, ocular biometric measurement, and non-dilation fundus photography. The differences in the prevalence of TF in basic characteristics and ocular biometric parameters were compared. Based on the equivalent spherical (SE), refractive status was divided into the non-myopia group (SE＞－0.50 D) and the myopia group (SE≤－0.50 D). The myopia group was further divided into mild myopia group (－3.00 D＜SE≤－0.50 D), moderate myopia group (－6.00 D＜SE≤－3.00 D), and high myopia group (SE≤－6.00 D). According to the axis length (AL), the subjects were divided into AL＜24 mm group, 24-26 mm group, and ＞26 mm group. The logistic regression was used to analyze the risk factors affecting TF. Trend tests were performed for each risk factor and TF. ResultsOf the 346 subjects, 324 (93.6%, 324/346) were myopia, of whom 73 (21.1%, 73/346), 167 (48.3%, 167/346), and 84 (24.3%, 84/346) were mild myopia, moderate myopia, and high myopia, respectively; 22 (6.4%, 22/346) were non-myopia. There were 294 (85.0%, 294/346) students with TF in the macula, including 9 (40.91%, 9/22), 58 (79.45%, 58/73), 145 (86.83%, 145/167), and 82 (97.62%, 82/84) in non-myopia, low myopia, moderate myopia, and high myopia group, respectively; 52 (15.0%, 52/346) students were without TF in the macula. There were statistically significant gender differences (χ2=4.47), SE (t=6.29), AL (t=－8.29), anterior chamber depth (Z=－2.62), lens thickness (Z=－2.23), and average corneal radius (Z=－3.58) between students with and without TF in the macula (P＜0.05). Spherical equivalent and axial length were independent risk factors for TF and its severity (P≤0.001). With an increasing degree of myopia, and increasing axial length, the risk of TF increased (P for trend＜0.001). ConclusionsThe prevalence of TF is 85.0% among Tianjin Medical University students. TF is detected in the fundus of no myopia, mild myopia, moderate myopia and high myopia. The degree of myopia is higher, the AL is longer, the possibility of TF is higher.