第一章概述ChapterOneOverview课件

第一章

概述ChapterOneOverview定义Definition低视力是指患者的视觉功能减退到一定程度，且不能用常规的屈光矫正方法或者手术、药物等治疗达到期望的视力水平者。Lowvisionreferstoapatientwhosevisionisreducedtoacertainextentthatcannotbecorrectedtotheexpectedvisionacuitywithconventionalrefractivecorrectionmethodsortreatmentssuchassurgery,medicines,etc.表现Symptoms视力下降Decreasedvision视野缺损visualfielddefect对比敏感度、色觉、暗适应、眼球运动或双眼视功能的异常Possibleabnormalitiesincontrastsensitivity,colorvision,darkadaptation,eyeballmovement,orbinocularvision需要借助其他装置或训练来改善和提高视觉能力和活动能力Requiringtheassistofotherdevicesand(or)trainingtoimproveandenhancevisionandmobilityabilities.释义Interpretation低视力并不是指某一种疾病Lowvisiondoesnotindicateadisease也不是一种屈光不正Notarefractiveerror是一个功能性定义，可用于任何因疾病或功能紊乱而影响视觉系统的患者。Afunctionaldefinitionthatcanbeusedinanypatientwhosevisualsystemisaffectedbyadiseaseordysfunction.释义Interpretation这一概念并不包括单眼视觉功能下降的患者Patientswithreducedmonocularvisionarenotincludedinthisconcept.定义中“常规的屈光矫正方法”是指用于矫正屈光不正和(或)近附加不超过+4.00DS的眼镜和接触镜。The“conventionalrefractivecorrectionmethods”includedinthedefinitionreferstotheglassesandcontactlensusedtocorrectrefractiveerrorand(or)addwhicharenomorethan+4.00DS.定义Definition（Faye）20世纪50年代，Faye将低视力定义为：视力及视野均不正常，且视力损害不能用普通眼镜矫正，并由于视功能损害造成日常生活困难。Inthe1950s,Fayedefinedlowvisionasabnormalvisionandvisualfieldwhosevisualimpairmentcannotbecorrectedwithordinaryglasses,withdifficultiesindailylifecausedbyvisualfunctionimpairment.该概念承认患者仍然存在一定的视力，且这个视力不能简单地认为是光感。Thisconceptacknowledgesthatthepatientstillhassomevision,whichcannotsimplybeconsideredalightperception.诊断标准（1973年）Diagnosticcriteria(1973)1973年，世界卫生组织（WHO）制定了盲及低视力的诊断标准与分级。In1973,theWorldHealthOrganization(WHO)formulatedthediagnosticstandardandgradingofblindnessandlowvision.低视力的诊断标准：双眼中好眼最佳矫正视力小于0.3且大于0.05。Thediagnosticcriteriaforlowvisionatthattimewerethatthebestcorrectedvisionofthestrongereyebelessthan0.3andgreaterthan0.05.定义（1992年）Definition1992年7月，将低视力的定义进行了合适的修订，双眼的视觉功能减退到一定程度，且不能用手术、药物等常规的屈光矫正方法提高视力，生活和工作能力丧失或部分丧失者。AppropriaterevisionofthedefinitionoflowvisionwasconductedinJuly1992.

Apatientwhosevisualfunctionofbotheyesisreducedtoacertainextentandcannotbeimprovedbysurgery,medicine,andconventionalrefractivecorrectionmethods,resultinginpartialorcompletelossoftheabilitytoliveandwork.部分视力或视力损害等都是低视力的同义词。Partialvisionorimpairedvisionaresynonymsforlowvision.低视力术语诠释（1985）InterpretationofLowVisionTerms(1985)术语Term诠释Interpretations概念Concept视觉疾病Visualdiseases组织学结构的异常Abnormalitiesinhistologicalstructure眼科概念Ophthalmologyconcepts视觉损害Visualimpairment视觉功能减退(视力、视野…)Visualdysfunction(vision,visualfield)医学概念Medicalconcepts视觉失能Visualdysfunction从事某种作业的能力下降（阅读、定向、自主行动）Reducedabilitiesinsomeactivities（reading,autonomousmovement）

功能概念Functionalconcepts视觉残疾Visualdisability因视觉伤残不能履行某种行为(包括个人及社会的行为)Inabilitytoperformsomeacts(includingpersonalandsocialacts)duetovisualimpairmentand(or)disability社会概念Socialconcepts我国盲及低视力的标准（1987年）

BlindnessandLowVisionStandardinChina(1987)类别Category级别Grading最佳矫正视力Bestcorrectedvision(StrongerEye)盲Blindness一级盲Grade1blindness<0.02~光感，或视野半径<5°<0.02~lightperception,orradiusofvisualfield<5°二级盲Grade2blindness<0.05~0.02,或视野半径<10°<0.05-0.02,orradiusofvisualfield<10°低视力Lowvision一级低视力Grade1lowvision<0.1~0.05二级低视力Grade2lowvision<0.3~0.1注意事项Note:盲或低视力均指双眼而言：且以视力较好一眼为准。Blindnessorlowvisionreferstobotheyes:anditisdeterminedaccordingtotheonewithbettervision.如仅有一眼为盲或低视力，而另一眼的视力达到或优于0.3,则不属于视力残疾范围。Ifonlyoneeyewithblindnessorlowvision,andthevisionoftheothereyeis0.3orbetter,itisnotintherangeofvisualdisability.最佳矫正视力，是以适当镜片矫正所能达到的最好视力，或以针孔镜所测得的视力。Bestcorrectedvisionisthebestvisionthatcanbeachievedwithproperlenscorrection,orthevisionmeasuredbypinholelens.视野半径<10°者，不论其视力如何均属于盲。Thosewhoseradiusofvisualfieldis＜10°areblindregardlessoftheirvision.新WHO视觉损伤分类标准（2003）NewWHOClassificationStandardforVisualImpairment日常生活远视力Distancevisionindailylife分类Classifications视力低于Visionbelow视力等于或优于Visionequalorbetterthan轻度或无视力损伤Mildornovisualimpairment(0)

0.3中度视力损伤Moderatevisualimpairment(1)0.30.1重度视力损伤Severevisualimpairment(2)0.10.05盲(3)Blindness(3)0.050.02盲(4)Blindness(4)0.02光感Lightperception盲(5)Blindness(5)

无光感

Nolightperception日常生活远视力是指一个人在日常屈光状态下所测远视力，如果受检者未配戴远用矫正眼镜，则检查裸眼视力Thedistancevisionindailylifereferstothedistancevisionmeasuredunderthedailyrefractivestatus.Forexample,examinethenakedvisionifthesubjectdoesnotwearcorrectiveglassesfordistancevision;受检者配戴远用矫正眼镜，并经常戴用，则检查戴镜后视力Examinethevisionwithglassesifthesubjectwearscorrectiveglassesfordistancevisionandthefrequencyishigh受检者配戴远用矫正眼镜，但并不经常戴用，则检查裸眼视力。Examinethenakedvisionifthesubjectwearscorrectiveglassesfordistancevisionbutthefrequencyislow.注意事项Note:低视力诊断参考因素ReferenceFactorsforDiagnosisofLowVision当前国际上通用的低视力与盲的诊断标准是依据视力和视野半径。Atpresent,thediagnosticstandardforlowvisionandblindnessarebasedonthevisionandradiusofvisualfield.由于视野半径不足，患者视物的范围将大大缩小，看物体时，感觉有阴影挡住视线，甚至视野范围某些区域完全黑影，看不到东西。Thisisbecausethatiftheradiusofvisualfieldisnotenough,thescopeofthepatient'svisionwillbegreatlyreduced,andwhenlookingatanobject,thepatientfeelsthatthereisashadowblockingtheview,evensomeareasofthevisualfieldrangearecompletelydarkwithoutanythingcanbeseen.比如青光眼患者会出现管状视野，中心视力可以达到1.0,但是由于视野狭窄，无法注视周边物体，严重影响患者的生活或者工作。Forexample,glaucomapatientswillhaveatubularvisualfieldandtheircentralvisioncanreach1.0,buttheycannotlookattheperipheralobjectsduetothenarrowvisualfield,whichseriouslyaffectstheirlifeorwork.低视力诊断注意事项PrecautionsinLowVisionDiagnosis1.低视力是双眼中好眼的矫正视力低于诊断标准，即使一只眼的矫正视力很差，接近盲，但另一只眼的矫正视力超出低视力诊断标准(≥0.3),该患者不属于低视力。1.Lowvisionmeansthatthecorrectedvisionofthestrongereyeislowerthanthediagnosticstandard.Evenifthecorrectedvisionofoneeyeispoorandclosetoblindness,thecorrectedvisionoftheothereyeexceedsthediagnosticstandardoflowvision(≥0.3),thepatientcannotbediagnosedwithlowvision.2.应具有残余视力。2.Shouldhaveresidualvision.3.标准的屈光矫正方法是指应用常规眼镜或接触镜，不包括+4.00DS以上的近附加，不包括针孔镜、望远镜等。3.Thestandardrefractivecorrectionmethodreferstotheapplicationofconventionalglassesorcontactlens,excludingaddabove+4.00DS,pinholelenses,ortelescopes,etc.4.即使视力在正常范围，但视野半径低于10°,仍属于盲。4.Evenifthevisioniswithinthenormalrange,theradiusofvisualfieldislowerthan10°,itstillbelongstoblindness.我国低视力病因EtiologyoflowvisioninChinaEtiologyoflowvisioninChinaCataractOpacityofCorneaRetinalDiseaseHighmyopiaLoss/atrophyoftheeyeballGlaucomaothers三大致盲性眼病Threemajoreyediseasesofblindness白内障Cataracts青光眼Glaucoma黄斑变性MaculardegenerationIncreasedintraocularpressureDamageopticnerve欧洲低视力病因CausesoflowvisioninEurope年龄相关性黄斑变性等眼球后极部病变：43.2%Age-relatedmaculardegeneration,accountingfor43.2%青光眼：9.1%Glaucoma:9.1%年龄相关性白内障：6.7%Age-relatedcataract:6.7%美洲低视力病因CausesoflowvisionintheAmericas40岁以上人群中，年龄相关性黄斑变性是每年的新增盲和低视力病例中最重要原因，占40%～50%的比例。Age-relatedmaculardegenerationisthemostimportantcauseofannualnewblindnessandlowvisioninpeopleover40yearsold,accountingfor40%-50%.其余依次为白内障、青光眼、糖尿病性视网膜病变。Followedbycataract,glaucoma,anddiabeticretinopathy.亚洲低视力病因CausesoflowvisioninAsia亚洲地区的低视力和盲患病率相对高，白内障是最主要的致病原因。TheprevalenceoflowvisionandblindnessisrelativelyhighinAsia,andcataractsistheleadingcauseofthedisease.这与亚洲地区靠近赤道，纬度较高，接受较多的太阳紫外线的照射有关系。It’srelatedtothefactthatAsiaisclosertotheequator,withhigherlatitudesandmoreexposuretosolarultravioletradiation.非洲低视力病因Causesoflowvi