简介:目的探讨一组特殊设计镜片对周边屈光度、周边清晰视力范围和主观感受的影响。方法3例(4眼)被试者,年龄22-31岁,屈光度-2.0D,按随机顺序分别在单眼配戴普通非球面镜片、成长乐镜片、视特保大、中、小光区镜片的情况下进行周边屈光度、周边清晰视力范围测量和主观评分,主观评分包括远距和近距戴镜舒适度、清晰度和接受度。结果配戴5种镜片时,被试眼相对周边屈光度均为远视状态,远视度数随周边角度增加而增加。配戴普通非球面镜片和视特保大光区镜片时周边远视度数最大,视特保中光区镜片其次,成长乐镜片和视特保小光区镜片最小;配戴普通非球面镜片和视特保大光区镜片时的周边清晰视力范围最大,其次是视特保中光区镜片,最小的是成长乐镜片和视特保小光区镜片;远距评分为普通非球面镜片最高,视特保大光区镜片其次,然后为视特保中光区镜片,成长乐镜片及视特保小光区镜片最差;近距评分视特保大光区镜片接近普通非球面镜片,视特保中光区镜片和成长乐镜片其次,视特保小光区镜片最差。结论不同设计的中周部加光镜片对改变周边屈光度的作用存在差异,其配戴后的顺应性与镜片改变周边屈光度的程度呈负相关。
简介:AIM:Toinvestigatewhethertheresponseofacentralhexagonalelementcorrespondingtothemacularareainconventionalmultifocalelectroretinography(mfERG)testswasthesameasthatofexperimentalmfERGusingsinglecentralhexagonalelementstimulation.METHODS:Prospective,observationalstudy.Thirtyhealthysubjectswereincludedinthisstudy.mfERGrecordingswereperformedaccordingtotwoprotocols:stimuluswith37hexagonalelements(protocol1),andstimuluswithasinglecentralelementcreatedbydeactivatingtheother36hexagonalelements(protocol2).Wecompareddifferencesbetweenring1parametersineachprotocol.RESULTS:Inprotocol1,thefirstpositivecomponent(P1)implicittimeandP1amplitudewere37.8±1.8msand6.3±2.7μV.Aftersingleelementstimulation(protocol2),doublepositivewavesappeared.TheimplicittimeandamplitudeofP1were40.7±2.4ms(P<0.001)and9.1±3.3μV(P=0.001),respectively.Theimplicittimeandamplitudeofthesecondpositivecomponent(P2)were68.0±4.5ms(P<0.001,comparedwithP1inprotocol1)and12.3±4.7μV(P<0.001,comparedwithP1inprotocol1),respectively.TheamplitudeofP2inprotocol2wasabouttwotimeshigherthanthatofP1inprotocol1.CONCLUSION:mfERGresponsesofacentralhexagonalelementinasingleelementstimulationprotocolaredifferentfromthoseofmultipleelementstimulation.Thepositivewaveismoreenhancedcomparedtothatoftheconventionalprotocolanditelongatedintotwowavelets.
简介:目的了解安阳县≥40岁自觉视力障碍的农民盲与低视力的患病率及致盲原因.方法安阳县各行政村中,≥40岁自觉视力障碍的农民为筛查对象.采用WHO盲与低视力标准和白内障诊断标准.由眼科医生作眼部检查.对所有视力<0.3的患眼进行主要病因诊断,确诊所有白内障患者,并筛选出需手术治疗者.结果共检查853例,盲目患者23例,患病率2.70%,低视力患者99例,患病率4.27%,致盲的主要眼病依次为白内障、角膜病、青光眼、视网膜病等.共筛查出533例白内障,行白内障手术治疗301人次,脱残率98%,脱盲率99.34%.结论白内障仍是盲和低视力的首要病因,防盲治盲的重点仍是白内障复明手术.
简介:目的:对湖北地区20~29岁人群的角膜散光情况与不同近视度数的关系进行调查,找出其变化规律。方法:用角膜地形图对随机抽取的2254例湖北地区20~29岁青年居民进行散光度、轴向及近视度数的测定,并分析其变化规律。结果:湖北地区20~29岁居民中,各个近视度段散光在26°~150°范围内所占人数比例最大,各个近视度段均呈现顺规散光人数多于逆规散光。其中女性高度近视段约为75.3%,中度近视段约为82.7%,低度近视段约为87.2%;男性高度近视段约为74.6%,中度近视段约为83.0%,低度近视段约为82.3%。20~29岁男性高度近视段顺规散光人数比例高于其他两组;女性低度近视段顺规散光人数比例低于其他两组,差异有统计学意义。20~29岁人群中女性中度近视段顺规散光人数比例高于同近视度男性组,且女性总体组顺规散光人数比例高于男性总体组,差异有统计学意义。20~29岁男、女性高度近视组200°以内散光人数比例均低于中度近视组,差异有统计学意义。结论:湖北地区20~29岁居民中,各个近视度段散光在26°~150°范围内所占人数比例最大,且各个近视度段不论男女均呈现顺规散光人数多于逆规散光;男性高度近视段顺规散光人数比例高于其他两组,女性低度近视段顺规散光人数比例低于其他两组;女性中度近视段顺规散光人数比例高于同近视度男性组,且女性总体组顺规散光人数比例高于男性总体组;男、女性高度近视组200°以内散光人数比例均低于中度近视组。
简介:AIM:ToIntroduceanewspecializedvisualacuitychartforamblyopicchildrenaged3-5yearsoldanditsclinicalapplications.METHODS:ThenewvisualacuitychartandnotationsweredesignedbasedonWeber-Fechnerlaw.Theoptotypeswereredagainstawhitebackgroundandwerespeciallyshapedfourbasicgeometricsymbols:circle,square,triangle,andcross.Aregulargeometricprogressionoftheoptotypesizesanddistributionwasemployedtoarrangein14lines.Theprogressionrateoftheoptotypesizebetweentwolineswas1.2589andthetestingdistancewas3m.VisualacuityscorecouldberecordedaslogMARnotationordecimalnotation.Agestratifieddiagnosticcriteriaforamblyopiaestablishedbyconsensusstatementondiagnosisofamblyopia(2011)amongmembersoftheStrabismusandPediatricOphthalmologyGroup,OphthalmologySociety,ChineseMedicalAssociation(SPOGOSCMA)wereillustratedinthenewvisualacuitychart.RESULTS:Whenassessingvisualacuityinchildrenaged3-5yearsold,thisnewvisualacuitychartthatconsistsoffoursymmetricalshapes(triangle,square,cross,andcircle)overcameaninabilitytorecognizethelettersofthealphabetanddifficultiesindesignatingthedirectionofblackabstractsymbolssuchasthetumbling’E’orLandolt’C’,whichthesubjectswerepronetoloseinterestin.Thevisualacuityscoremayberecordedindifferentnotations:decimalacuityandlogMAR.Thesetwonotationscanbeeasilyconvertedeachotherintheneweyechart.Themeasurementsofthisnewchartnotonlyshowedasignificantcorrelationandagoodconsistencywiththeinternationalstandardlogarithmicvisualacuitychart(r=0.932,P<0.01),butalsoindicatedahightest-retestreliability(89%ofretestscoreswerewithin0.1logMARunitsoftheinitialtestscore).CONCLUSION:Theresultsofthisstudysupportthevalidityandreliabilityofdistancevisualacuitymeasurementsusingtheneweyechartinchildrenaged3to5yearsoverawiderangeofvisualacuities,andtheneweyechartisgreatforearl
简介:目的了解上海市普陀区4-7岁儿童阻塞性睡眠呼吸暂停低通气综合征(OSAHS)的患病率及相关危险因素,探讨问卷调查在筛选疑似病例中的价值。方法以班级为单位采取整群抽样的方法从上海市普陀区幼儿园及小学一年级中抽取4-7岁学生6000例,由学生家长填写问卷,再从中随机抽取无打鼾或轻微打鼾者10例,有频繁打鼾症状的儿童42例,行多导睡眠监测。结果实际调查人数5040(应答率为84.0%),有效问卷4045份(有效率为80.23%),按睡眠呼吸暂停低通气指数(AHI)≥5次/h、最低血氧饱和度(LSaO2)≤0.94为标准,根据多导睡眠监测结果,估算上海市4-7岁儿童OSAHS的患病率为3.91%。AHI与腺样体肥大相关性较强(偏相关系数为0.373);将问卷中打鼾、憋气、反复翻身、夜尿发生率等选项分配一个0-4分的数值,调查问卷得分与AHI呈正相关(r=0.518)。问卷中打鼾、张口呼吸选项的敏感度较高(95%、87%),特异性一般(67%、79%);憋气、憋醒选项敏感度一般(66%、29%),特异度较高(93%、100%);夜尿及反复翻身选项无统计学意义(P〉0.05)。结论上海市普陀区4-7岁儿童OSAHS的患病率估计为3.91%,腺样体肥大为患病主要原因;设计合理的调查问卷可用于初步筛选儿童OSAHS疑似病例,对早期诊断和治疗具有重要参考价值。