临夏州多民族青少年近视患病率调查及相关因素分析

目的：研究临夏州青少年近视患病率情况及影响近视发生的因素。

方法：采用整群抽样方法抽取6～18岁青少年8 683例作为研究对象,检测其视力、屈光度等,同时采用调查问卷收集其性别、年龄、民族、用眼习惯等资料。

结果：本次调查研究纳入的研究对象近视患病率为42.80%,不同民族研究对象近视患病率分别为藏族(59.05%)、汉族(46.71%)、东乡族(46.36%)、土族(45.24%)、撒拉族(41.30%)、保安族(40.61%)、回族(31.97%),差异有统计学意义(χ²=44.08,P=0.007)。多因素Logistic回归分析表明课间休息时在室外活动是近视的保护因素,而年龄、周末及节假日使用电子产品、在家学习使用房间同一照明是近视的危险因素。

结论：临夏州青少年近视患病率随年龄增大而升高,不同民族青少年近视患病率存在差异。教育部门与家庭应共同努力,增加青少年户外活动时间,改善青少年用眼环境,减缓青少年近视的发生发展。     

内蒙古自治区赤峰市青少年近视现状及影响因素

目的：分析赤峰市青少年人群的视力不良情况及近视患病率,探究影响近视发病的相关因素。

方法：于2019-09/12采取多阶段随机抽样方法在赤峰市选取小学四年级～高三年级学生2 070人进行问卷调查,并进行视力检查,分析该地区近视发生情况及影响因素。

结果：本研究纳入学生2 070人,视力不良发生率为56.96%,其中近视患病率52.22%。多因素Logistic回归分析显示,高年级、女性、有遗传史、常吃甜食、油炸食物、不吃早餐、较长的作业及补习班时间、使用移动设备、躺着或趴着用眼、走路或乘车用眼、一次用眼时间过长是近视的危险因素; 而无其他视力不良、食用新鲜水果、调整桌椅高度、常做眼保健操、课间在户外活动、保持一尺的坐姿、家长及老师经常监督坐姿、较少观看电视、增加持续运动及睡眠时间等是近视的保护因素。

结论：赤峰市青少年的近视率普遍较高,应积极关注学生个人情况,改善学生校内和校外用眼环境,纠正学生不良用眼习惯,增加学生户外运动及睡眠时间。     

成都市新都区小学生近视流行病学研究

目的：调查成都市新都区小学生近视现状,分析本地区小学生近视的流行病学特点及相关影响因素。

方法：采用分层整群随机抽样调查的方法,抽取成都市新都区4所小学的一年级到六年级学生,每个年级3个班,分别进行眼科检查和问卷调查,用SPSS21.0软件进行统计分析。

结果：共有3 324名学生参与本次调查,近视的学生1 124人,近视率33.81%。不同性别、不同年龄、不同年级、吃水果蔬菜和喝牛奶频次、父母监督和提醒学生用眼习惯频次、在家看书写字光线情况、每天连续家庭作业及看书时间、睡眠时间、每天课外活动时间、课间休息时去户外活动或做眼保健操频次、躺着看书或在晃动的车内看书频次、看书写字姿势以及父母双方患有近视情况的学生近视患病情况存在不同(P<0.05)。多因素回归分析发现：年级、性别、父母监督和提醒用眼习惯、在家看书写字的光线、每天连续家庭作业及看书时间、每天课外活动时间、躺着看书或在晃动的车内看书、看书写字姿势是否正确、父母近视情况均为近视的独立影响因素,其中父母监督和提醒用眼习惯为影响近视的保护因素,其余各指标均为危险因素。

结论：青少年近视与环境、遗传等多种因素有关,应尽早采取相应措施,延缓其发生发展。     

北京市海淀地区小学生近视现况调查与影响因素分析

目的：探讨北京市海淀地区小学生近视现况与影响因素。

方法：按照整群分层抽样法选择北京市一至三年级小学生801名,现场问卷调查共计801份,符合年龄7～10周岁的筛查对象757名,有效问卷共757份,患病率为24.4%。通过问卷调查的方式,收集所有对象基线资料,对比引起近视的相关资料,采用Logistic回归方程进行计算,分析产生近视的因素。

结果：看书用眼时间、电子产品使用时间、父母近视情况、户外活动时间、注意读写姿势均是导致小学生近视的相关因素。将上述有差异因素经过Logistic回归方程计算得以证实。

结论：北京市小学生近视率已经达到较高的水平,在家庭、日常生活及学生自身上均存在较多的问题,需针对相关因素进行防控,预防及延缓近视的发生,促进小学生的视力健康。     

青海省高海拔藏族地区初中生近视率的调查研究

目的：了解青海省高海拔藏族地区初中生近视率及影响近视发生的因素,为近视的预防提供依据。 方法：采用分层整群抽样方法抽取2209名初中生作为调查对象,采用自制调查问卷收集性别、年龄、民族、年级、用眼行为、体育锻炼以及父母视力情况等,同时检测角膜曲率、前房深度和眼轴长度。 结果：研究对象近视患病率为48.02%,其中轻度近视、中度近视和高度近视分别占40.74%,35.31%和23.96%。角膜曲率、前房深度和眼轴长度在视力正常与不同程度近视研究对象间存在统计学差异（P〈0.05）。不同性别、民族、年级、视近距离、坐姿、眼保健操、每周户外活动时间以及父母视力情况研究对象近视患病率间存在统计学差异（ P〈0.05）。 Logistic回归分析表明性别、民族、年级、视近距离、坐姿、眼保健操、每周户外活动时间以及父母视力情况是影响近视发生的因素。 结论：坐姿不正确、父母近视、视近距离〈20 cm、眼保健操不正确以及户外活动时间少等引起初中生近视的主要原因,应针对上述因素采取有效的预防控制措施。     

山西省高平市青少年儿童近视现状及影响因素分析

目的：分析山西省高平市青少年儿童视力发育情况及近视患病率,探讨近视发生的影响因素。

方法：于2018-11/2019-01采取多阶段抽样方法在山西省高平市选取幼儿园大班学生181人、小学生948人、初中生432人、高中生244人进行问卷调查,并进行视力和屈光度检测,分析该地区青少年儿童近视发生情况及其影响因素。

结果：本研究纳入学生1 805人,视力不良检出率为78.28%(1413/1805),近视患病率为64.38%(1162/1805),近视学生戴镜率为51.46%(598/1162)。随着学习阶段和年龄的增长,近视患病率不断升高,且女生近视患病率(66.81%)高于男生(61.73%),城区学生近视患病率(66.54%)高于乡镇学生(61.52%)。回归分析结果显示,学习距离是近视发生的保护因素,而每日学习时间、喜食甜食、初次视力下降时间、初次视力下降时间与戴镜时间的间隔时间均是近视发生的危险因素。

结论：山西省高平市青少年儿童近视患病率较高,长时间近距离用眼、饮食搭配不合理、预防和干预措施滞后均是导致近视发生的影响因素。     

湘潭市中小学生眼屈光不正及相关因素的流行病学调查

目的：调查湘潭市中小学生视力不良、屈光不正患病状况及近视主要影响因素,为中小学生近视防控提供科学依据。

方法：采取整群随机抽样。2018-09/12,在湘潭市区随机抽取5所全日制小学和3所中学,共6 164名学生作为调查对象,进行裸眼视力、矫正视力、眼位检查,双眼中任一眼裸眼远视力低于5.0者,进一步测量双眼屈光度数。自制调查问卷以了解近视发生相关因素。

结果：在6 164名学生中日常生活视力不良男生检出率为40.3%(1 249/3 099),女生检出率为43.8%(1 343/3 065)(P<0.01)。中小学男生近视患病率59.1% ,女生近视患病率68.7%(P<0.01)。小学生近视患病率为44.1%,远视患病率为3.0% 。初中生近视患病率为71.3%,远视患病率为 1.7%。多因素回归分析显示,年级(初中)、性别(女)、每天写作业时间(>2h)、平均每天睡眠时间(≤8h)、父母为近视是中小学生近视发生的独立危险因素(OR=1.48、1.55、1.26、1.58、2.13,均P<0.05)。

结论：湘潭市中小学生视力不良检出率高,近视发病率高,学生近视与多因素综合作用有关,需进行针对性的综合干预。     

山东省龙口市7～18岁中小学生近视患病率调查分析

目的：调查研究山东省龙口市7～18岁中小学生近视患病率情况,为近视防控提供科学依据。

方法：采用横断面随机整群抽样的方法于2015-01/12对山东省龙口市7～18岁在校学生以学校为抽样单位进行近视情况的调查,共抽取学校58所,有效抽样61 036人。按地域分为城市、城乡结合部及农村3类地区。由相关工作人员在全程质量控制下采用标准对数视力表检查受检者双眼裸眼视力,采用自动验光仪(TOPCON-RM8900)在非散瞳情况下行电脑验光检查。采用Microsoft Excel工作表建立数据库,SPSS 21.0软件进行统计学分析。

结果：2015年龙口市7～18岁中小学生的总体近视患病率为49.81%,11～12岁时总体近视患病率增幅最快,13岁时轻度近视患病率最高。男性和女性总体近视患病率分别为46.41%、53.39%,女性总体近视患病率高于男性。城市、城乡结合部及农村地区学生总体近视患病率分别为55.18%、49.75%、44.47%,城市学生总体近视患病率明显高于城乡结合部及农村地区。总体近视患病率与年龄呈正相关(r_s=0.943,P<0.05),即总体近视患病率随年龄的增长而逐渐升高。

结论：山东省龙口市2015年中小学生近视患病率较高,且随年龄的增长而逐渐升高,女性高于男性,城市高于城乡结合部及农村地区。     

重庆酉阳县土家族青少年屈光不正及相关因素的流行病学调查

目的：了解重庆市酉阳县土家族青少年人群屈光不正的患病率及其影响因素。方法：横断面调查研究。采用分层整群抽样的方法,对重庆市酉阳县城镇和乡村各2所中学（初中和高中）的土家族青少年共973例进行眼科检查。通过电脑自动验光及1%环戊通滴眼液扩瞳后检影验光获得青少年的屈光状态,以调查问卷方式了解并分析近视发生的相关因素,包括户外活动时间、父母屈光状态等。采用Pearson卡方检验以及Pearson和Spearman相关性分析对数据进行处理。结果：近视（等效球镜度≤-0.50 D）、远视（等效球镜度≥+0.50 D）以及散光（柱镜度≤-0.50 D）的患病率分别为66.3%（645例）,17.5%（170例）和15.1%（147例）。高度近视检出25例,占总检出人数的2.6%。男生近视患病率（59.8%）显著低于女生（72.5%） （ χ 2 =17.53,P < 0.001）。城镇青少年近视患病率（77.9%）显著高于乡村青少年（51.6%） （ χ 2 =74.12,P < 0.001）。随着年龄增长,近视患病率逐渐升高（ χ 2 =84.70,P < 0.001）,远视患病率逐渐降低（ χ 2 =78.30,P < 0.001）。近视的土家族青少年中,父母双方均存在（ χ 2 =10.85,P=0.001）或单方存在（ χ 2 =56.01,P < 0.001）近视的概率显著高于非近视青少年。青少年户外活动时间与屈光状态呈显著正相关（r 2 =0.781,P < 0.001）。结论：重庆市酉阳县土家族青少年女性近视患病率较高;城镇青少年近视患病率高于乡村;近视发病与父母近视和户外活动时间相关。     

湖南省怀化市中小学生近视现况调查及影响因素分析

目的调查湖南省怀化市中小学生近视患病现状并分析其相关因素。设计横断面研究。研究对象湖南省怀化市鹤城区3~12年级学生2103名。方法采用分层整群抽样方法,2014年9~12月对怀化市鹤城区6所学校中小学生进行视力检查、非睫状肌麻痹下自动验光和问卷调查。近视定义为等效球镜度(SE)≤-0.50 D。应用非条件Logistic回归模型对可能与近视发生相关的33项因素进行多因素分析。主要指标近视患病率。结果在入选的2103名学生中,2064名(98.1%)(平均年龄12.5±2.8岁,范围7~18岁)参与了调查。近视患病率为46.3%(95%CI:44.1%~48.5%),小学生为22.1%(95%CI:19.3%~24.9%),初中生为53.8%(95%CI:50.0%~57.6%),高中生为74.4%(95%CI:70.8%~78.1%)。近视患病率随着年级增高呈增长趋势(χ~2=425.626,P=0.000)。女生近视患病率50.4%(95%可信区间:47.2%~53.6%)高于男生42.8%(95%可信区间:39.9%~45.7%)(χ~2=12.043,P=0.001)。乡村小学和城区小学的近视患病率无显著性差异(χ~2=0.140,P=0.708)。近视学生中69.2%(660/954)配戴眼镜。Logistic回归分析显示,近视的危险因素为父母近视、更长的近距离用眼时间、更短的近距离用眼距离、更少的睡眠时间、照明过暗。课桌高度合适、户外活动、几乎不看电视或玩电脑、无不良用眼行为和习惯是近视的保护因素。结论怀化市中小学生近视患病率较高,乡村学校的近视防治工作亦刻不容缓,视力保护的关键年龄在9岁以前。     

Segmentation and accuracy in copying and drawing: Experts and beginners

As part of an ongoing investigation into real-world copying and drawing, I recorded the eye-hand drawing strategies of 16 subjects with drawing experiences ranging from expert to novice while they copied a line drawing of a standing nude. The experts produced accurate copies whereas all the beginners produced marked inaccuracies of overall scaling, proportion and shape. Analysis of eye and hand movements showed that the experts alone segmented the original drawing into simple line sections that were copied one at a time using a direct eye-hand strategy not requiring intermediary encoding to visual memory. The results suggest that segmentation into simple lines defines the task-specific process of accurate copying, and that this process is restricted to experts, i.e. acquired through training and practice. Additional preliminary tests also suggest that a similar process may apply to drawing a model from life.     

Paraneoplastic and non-paraneoplastic retinopathy and optic neuropathy: Evaluation and management

Paraneoplastic syndromes involving the visual system are a heterogeneous group of disorders occurring in the setting of systemic malignancy. Timely recognition of one of these entities can facilitate early detection and treatment of an unsuspected, underlying malignancy, sometimes months before it would have otherwise presented, and gives the patient an increased chance at survival. We outline the clinical features, pathogenesis, and treatment strategies for the retinal- and optic nerve–based paraneoplastic syndromes: cancer-associated retinopathy; melanoma-associated retinopathy; paraneoplastic vitelliform maculopathy; bilateral diffuse uveal melanocytic proliferation; paraneoplastic optic neuropathy; and polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome. Distinguishing these disorders from their non-paraneoplastic counterparts (e.g., autoimmune-related retinopathy and optic neuropathy, and acute zonal occult outer retinopathy) and determining appropriate systemic evaluation for the responsible tumor can be challenging. In addition, we discuss the utility and interpretation of autoantibody testing.     

Sensitivity to first- and second-order motion and form in children and adults

We compared the sensitivity of adults and children aged 3-10 years to first- and second-order motion and form. For first-order stimuli, at all ages sensitivity was better for motion than form, and motion thresholds were better at 6 Hz than at 1.5 Hz. For second-order stimuli, at all ages sensitivity was better for form than motion, and motion thresholds were better at 0.25 cyc/deg than at 1 cyc/deg. Thresholds became adult-like later for motion than for form and later for first-order than second-order stimuli. For first-order stimuli, the changes with age were larger and more protracted.     

Nodes and nodal points and lines in eyes and other optical systems

The typical stigmatic optical system has two nodal points: an incident nodal point and an emergent nodal point. A ray through the incident nodal point emerges from the system through the emergent nodal point with its direction unchanged. In the presence of astigmatism nodal points are not possible in most cases. Instead there are structures, called nodes in this paper, of which nodal points are special cases. Because of astigmatism most eyes do not have nodal points a fact with obvious implications for concepts, such as the visual axis, which are based on nodal points. In order to gain insight into the issues this paper develops a general theory of nodes which holds for optical systems in general, including eyes, and makes particular allowance for astigmatism and relative decentration of refracting elements in the system. Key concepts are the incident and emergent nodal characteristics of the optical system. They are represented by 2 × 2 matrices whose eigenstructures define the nature and longitudinal position of the nodes. If a system's nodal characteristic is a scalar matrix then the node is a nodal point. Otherwise there are several possibilities: Firstly, a node may take the form of a single nodal line. Second, a node may consist of two separated nodal lines reminiscent of the familiar interval of Sturm although the nodal lines are not necessarily orthogonal. Third, a node may have no obvious nodal line or point. In the second and third of these classes one can define mid-nodal ellipses. Astigmatic systems exist with nodal points and stigmatic systems exist with no nodal points. The nodal centre may serve as an approximation for a nodal point if the node is not a point. Examples in the Appendix , including a model eye, illustrate the several possibilities.     

Ethics and optometry: concepts and applications

Ethics refers both to the study of behaviour, and moral principals. The related concepts of justice and law are also relevant to optometry. A profession typically claims specialist knowledge and ethical behaviour – putting the interests of clients above its own. However, professional codes fail as ethical directives, and their goals are questioned. Beginning with broad principles, institutional ethics and issues of general health care provision are considered, and applications to optometry are made. Ethical theory can guide us in interacting with our patients, utilising resources and ordering priorities. The conservative approach to consumerism and advertising is defended on the basis of protecting public and professional interests. Ethical behaviour can be fostered, and this process should begin in undergraduate education.     

Nutritional antioxidants and age-related cataract and maculopathy

Loss of vision is the second greatest, next to death, fear among the elderly. Age-related cataract (ARC) and maculopathy (ARM) are two major causes of blindness worldwide. There are several important reasons to study relationships between risk for ARC/ARM and nutrition: (1) because it is likely that the same nutritional practices that are associated with prolonged eye function will also be associated with delayed age-related compromises to other organs, and perhaps, aging in general, (2) surgical resources are insufficient to provide economic and safe surgeries for cataract and do not provide a cure for ARM, and (3) there will be considerable financial savings and improvements in quality of life if health rather than old age is extended, particularly given the rapidly growing elderly segment of our population. It is clear that oxidative stress is associated with compromises to the lens and retina. Recent literature indicates that antioxidants may ameliorate the risk for ARC and ARM. Given the association between oxidative damage and age-related eye debilities, it is not surprising that over 70 studies have attempted to relate antioxidant intake to risk for ARC and ARM. This article will review epidemiological literature about ARC and ARM with emphasis on roles for vitamins C and E and carotenoids. Since glycation and glycoxidation are major molecular insults which involve an oxidative stress component, we also review new literature that relates dietary carbohydrate intake to risk for ARC and ARM. To evaluate dietary effects as a whole, several studies have tried to relate dietary patterns to risk for ARC. We will also give some attention to this emerging research. While data from the observational studies generally support a protective role for antioxidants in foods or supplements, results from intervention trials are less encouraging with respect to limiting risk for ARC/ARM prevalence or progress through antioxidant supplementations, or maintaining higher levels of antioxidants either in diet or blood. Without more information it is difficult to parse these results. It would be worthwhile to determine why the various types of studies are not yielding similar results. However, there are many common insults and mechanistic compromises that are associated with aging, and proper nutrition early in life may address some of these compromises and provide for extended youthful function later in life. Indeed, proper nutrition, possibly including use of antioxidant supplements for the nutritionally impoverished, along with healthy life styles may provide the least costly and most practical means to delay ARC and ARM. Further studies should be devoted to identifying the most effective strategy to prevent or delay the development and progress of ARC/ARM. The efforts should include identifying the right nutrient(s), defining useful levels of the nutrient(s), and determining the age when the supplementation should begin.     

Exogenous attention and color perception: performance and appearance of saturation and hue

Exogenous covert attention is an automatic, transient form of attention that can be triggered by sudden changes in the periphery. Here we test for the effects of attention on color perception. We used the methodology developed by Carrasco, Ling, and Read [Carrasco, M., Ling, S., & Read, S. (2004). Attention alters appearance. Nature Neuroscience, 7 (3) 308-313] to explore the effects of exogenous attention on appearance of saturation (Experiment 1) and of hue (Experiment 2). We also tested orientation discrimination performance for single stimuli defined by saturation or hue (Experiment 3). The results indicate that attention increases apparent saturation, but does not change apparent hue, notwithstanding the fact that it improves orientation discrimination for both saturation and hue stimuli.     

Aberration and contrast sensitivity comparison of aspherical and monofocal and multifocal intraocular lens eyes

BACKGROUND: Higher-order aberrations and contrast sensitivity were evaluated in patients who underwent phacoemulsification cataract extraction followed by implantation of aspherical, monofocal or multifocal intraocular lens (IOL) replacements. METHODS: In this comparative trial, 124 patients with an average age of 66.8+/-5.2 years and their 124 eyes were randomly divided into three surgical implantation groups to receive one of three types of IOLs in replacement of cataract lenses. The patients of group 1 were given an aspherical IOL Z9001 (AMO, Santa Ana, CA, USA) replacement, and group 2 was implanted a monofocal IOL SA60AT (Alcon, Fort Worth, TX, USA) and group 3 the multifocal IOL SA40N (AMO). Post-surgical best-corrected visual acuity, corneal aberrations, total ocular aberrations, pupil diameters, capsulorhexsis sizes and contrast sensitivity were measured and compared. RESULTS: There was no statistical difference for mean best-corrected visual acuity, pupil diameter, curvilinear capsulorhexis size and corneal aberration among the three groups. For the spherical aberration, fourth-order higher-order aberration and total ocular higher-order aberration, the SA40N group was higher than the SA60AT group and the SA60AT group was higher than the Z9001 group, and the differences between the three groups were statistically significant for these measurements. Contrast sensitivity was higher for the Z9001 group than the SA60AT group and the SA60AT group was higher than the SA40N group, and the difference was statistically significant in all the spatial frequencies of 3, 6, 12 and 18. CONCLUSIONS: Although the multifocal IOL can provide near vision, it can increase higher-order aberration and negatively influence contrast sensitivity. However, the aspherical IOL can reduce aberration and improve contrast sensitivity as compared with the monofocal IOL.