第一章概述ChapterOneOverview課件

第一章

概述ChapterOneOverview定義Definition低視力是指患者的視覺功能減退到一定程度，且不能用常規(guī)的屈光矯正方法或者手術(shù)、藥物等治療達到期望的視力水平者。Lowvisionreferstoapatientwhosevisionisreducedtoacertainextentthatcannotbecorrectedtotheexpectedvisionacuitywithconventionalrefractivecorrectionmethodsortreatmentssuchassurgery,medicines,etc.表現(xiàn)Symptoms視力下降Decreasedvision視野缺損visualfielddefect對比敏感度、色覺、暗適應(yīng)、眼球運動或雙眼視功能的異常Possibleabnormalitiesincontrastsensitivity,colorvision,darkadaptation,eyeballmovement,orbinocularvision需要借助其他裝置或訓(xùn)練來改善和提高視覺能力和活動能力Requiringtheassistofotherdevicesand(or)trainingtoimproveandenhancevisionandmobilityabilities.釋義Interpretation低視力并不是指某一種疾病Lowvisiondoesnotindicateadisease也不是一種屈光不正Notarefractiveerror是一個功能性定義，可用于任何因疾病或功能紊亂而影響視覺系統(tǒng)的患者。Afunctionaldefinitionthatcanbeusedinanypatientwhosevisualsystemisaffectedbyadiseaseordysfunction.釋義Interpretation這一概念并不包括單眼視覺功能下降的患者Patientswithreducedmonocularvisionarenotincludedinthisconcept.定義中“常規(guī)的屈光矯正方法”是指用于矯正屈光不正和(或)近附加不超過+4.00DS的眼鏡和接觸鏡。The“conventionalrefractivecorrectionmethods”includedinthedefinitionreferstotheglassesandcontactlensusedtocorrectrefractiveerrorand(or)addwhicharenomorethan+4.00DS.定義Definition（Faye）20世紀50年代，F(xiàn)aye將低視力定義為：視力及視野均不正常，且視力損害不能用普通眼鏡矯正，并由于視功能損害造成日常生活困難。Inthe1950s,Fayedefinedlowvisionasabnormalvisionandvisualfieldwhosevisualimpairmentcannotbecorrectedwithordinaryglasses,withdifficultiesindailylifecausedbyvisualfunctionimpairment.該概念承認患者仍然存在一定的視力，且這個視力不能簡單地認為是光感。Thisconceptacknowledgesthatthepatientstillhassomevision,whichcannotsimplybeconsideredalightperception.診斷標準（1973年）Diagnosticcriteria(1973)1973年，世界衛(wèi)生組織（WHO）制定了盲及低視力的診斷標準與分級。In1973,theWorldHealthOrganization(WHO)formulatedthediagnosticstandardandgradingofblindnessandlowvision.低視力的診斷標準：雙眼中好眼最佳矯正視力小于0.3且大于0.05。Thediagnosticcriteriaforlowvisionatthattimewerethatthebestcorrectedvisionofthestrongereyebelessthan0.3andgreaterthan0.05.定義（1992年）Definition1992年7月，將低視力的定義進行了合適的修訂，雙眼的視覺功能減退到一定程度，且不能用手術(shù)、藥物等常規(guī)的屈光矯正方法提高視力，生活和工作能力喪失或部分喪失者。AppropriaterevisionofthedefinitionoflowvisionwasconductedinJuly1992.

Apatientwhosevisualfunctionofbotheyesisreducedtoacertainextentandcannotbeimprovedbysurgery,medicine,andconventionalrefractivecorrectionmethods,resultinginpartialorcompletelossoftheabilitytoliveandwork.部分視力或視力損害等都是低視力的同義詞。Partialvisionorimpairedvisionaresynonymsforlowvision.低視力術(shù)語詮釋（1985）InterpretationofLowVisionTerms(1985)術(shù)語Term詮釋Interpretations概念Concept視覺疾病Visualdiseases組織學(xué)結(jié)構(gòu)的異常Abnormalitiesinhistologicalstructure眼科概念Ophthalmologyconcepts視覺損害Visualimpairment視覺功能減退(視力、視野…)Visualdysfunction(vision,visualfield)醫(yī)學(xué)概念Medicalconcepts視覺失能Visualdysfunction從事某種作業(yè)的能力下降（閱讀、定向、自主行動）Reducedabilitiesinsomeactivities（reading,autonomousmovement）

功能概念Functionalconcepts視覺殘疾Visualdisability因視覺傷殘不能履行某種行為(包括個人及社會的行為)Inabilitytoperformsomeacts(includingpersonalandsocialacts)duetovisualimpairmentand(or)disability社會概念Socialconcepts我國盲及低視力的標準（1987年）

BlindnessandLowVisionStandardinChina(1987)類別Category級別Grading最佳矯正視力Bestcorrectedvision(StrongerEye)盲Blindness一級盲Grade1blindness<0.02~光感，或視野半徑<5°<0.02~lightperception,orradiusofvisualfield<5°二級盲Grade2blindness<0.05~0.02,或視野半徑<10°<0.05-0.02,orradiusofvisualfield<10°低視力Lowvision一級低視力Grade1lowvision<0.1~0.05二級低視力Grade2lowvision<0.3~0.1注意事項Note:盲或低視力均指雙眼而言：且以視力較好一眼為準。Blindnessorlowvisionreferstobotheyes:anditisdeterminedaccordingtotheonewithbettervision.如僅有一眼為盲或低視力，而另一眼的視力達到或優(yōu)于0.3,則不屬于視力殘疾范圍。Ifonlyoneeyewithblindnessorlowvision,andthevisionoftheothereyeis0.3orbetter,itisnotintherangeofvisualdisability.最佳矯正視力，是以適當鏡片矯正所能達到的最好視力，或以針孔鏡所測得的視力。Bestcorrectedvisionisthebestvisionthatcanbeachievedwithproperlenscorrection,orthevisionmeasuredbypinholelens.視野半徑<10°者，不論其視力如何均屬于盲。Thosewhoseradiusofvisualfieldis＜10°areblindregardlessoftheirvision.新WHO視覺損傷分類標準（2003）NewWHOClassificationStandardforVisualImpairment日常生活遠視力Distancevisionindailylife分類Classifications視力低于Visionbelow視力等于或優(yōu)于Visionequalorbetterthan輕度或無視力損傷Mildornovisualimpairment(0)

0.3中度視力損傷Moderatevisualimpairment(1)0.30.1重度視力損傷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)

無光感

Nolightperception日常生活遠視力是指一個人在日常屈光狀態(tài)下所測遠視力，如果受檢者未配戴遠用矯正眼鏡，則檢查裸眼視力Thedistancevisionindailylifereferstothedistancevisionmeasuredunderthedailyrefractivestatus.Forexample,examinethenakedvisionifthesubjectdoesnotwearcorrectiveglassesfordistancevision;受檢者配戴遠用矯正眼鏡，并經(jīng)常戴用，則檢查戴鏡后視力Examinethevisionwithglassesifthesubjectwearscorrectiveglassesfordistancevisionandthefrequencyishigh受檢者配戴遠用矯正眼鏡，但并不經(jīng)常戴用，則檢查裸眼視力。Examinethenakedvisionifthesubjectwearscorrectiveglassesfordistancevisionbutthefrequencyislow.注意事項Note:低視力診斷參考因素ReferenceFactorsforDiagnosisofLowVision當前國際上通用的低視力與盲的診斷標準是依據(jù)視力和視野半徑。Atpresent,thediagnosticstandardforlowvisionandblindnessarebasedonthevisionandradiusofvisualfield.由于視野半徑不足，患者視物的范圍將大大縮小，看物體時，感覺有陰影擋住視線，甚至視野范圍某些區(qū)域完全黑影，看不到東西。Thisisbecausethatiftheradiusofvisualfieldisnotenough,thescopeofthepatient'svisionwillbegreatlyreduced,andwhenlookingatanobject,thepatientfeelsthatthereisashadowblockingtheview,evensomeareasofthevisualfieldrangearecompletelydarkwithoutanythingcanbeseen.比如青光眼患者會出現(xiàn)管狀視野，中心視力可以達到1.0,但是由于視野狹窄，無法注視周邊物體，嚴重影響患者的生活或者工作。Forexample,glaucomapatientswillhaveatubularvisualfieldandtheircentralvisioncanreach1.0,buttheycannotlookattheperipheralobjectsduetothenarrowvisualfield,whichseriouslyaffectstheirlifeorwork.低視力診斷注意事項PrecautionsinLowVisionDiagnosis1.低視力是雙眼中好眼的矯正視力低于診斷標準，即使一只眼的矯正視力很差，接近盲，但另一只眼的矯正視力超出低視力診斷標準(≥0.3),該患者不屬于低視力。1.Lowvisionmeansthatthecorrectedvisionofthestrongereyeislowerthanthediagnosticstandard.Evenifthecorrectedvisionofoneeyeispoorandclosetoblindness,thecorrectedvisionoftheothereyeexceedsthediagnosticstandardoflowvision(≥0.3),thepatientcannotbediagnosedwithlowvision.2.應(yīng)具有殘余視力。2.Shouldhaveresidualvision.3.標準的屈光矯正方法是指應(yīng)用常規(guī)眼鏡或接觸鏡，不包括+4.00DS以上的近附加，不包括針孔鏡、望遠鏡等。3.Thestandardrefractivecorrectionmethodreferstotheapplicationofconventionalglassesorcontactlens,excludingaddabove+4.00DS,pinholelenses,ortelescopes,etc.4.即使視力在正常范圍，但視野半徑低于10°,仍屬于盲。4.Evenifthevisioniswithinthenormalrange,theradiusofvisualfieldislowerthan10°,itstillbelongstoblindness.我國低視力病因EtiologyoflowvisioninChinaEtiologyoflowvisioninChinaCataractOpacityofCorneaRetinalDiseaseHighmyopiaLoss/atrophyoftheeyeballGlaucomaothers三大致盲性眼病Threemajoreyediseasesofblindness白內(nèi)障Cataracts青光眼Glaucoma黃斑變性MaculardegenerationIncreasedintraocularpressureDamageopticnerve歐洲低視力病因CausesoflowvisioninEurope年齡相關(guān)性黃斑變性等眼球后極部病變：43.2%Age-relatedmaculardegeneration,accountingfor43.2%青光眼：9.1%Glaucoma:9.1%年齡相關(guān)性白內(nèi)障：6.7%Age-relatedcataract:6.7%美洲低視力病因CausesoflowvisionintheAmericas40歲以上人群中，年齡相關(guān)性黃斑變性是每年的新增盲和低視力病例中最重要原因，占40%～50%的比例。Age-relatedmaculardegenerationisthemostimportantcauseofannualnewblindnessandlowvisioninpeopleover40yearsold,accountingfor40%-50%.其余依次為白內(nèi)障、青光眼、糖尿病性視網(wǎng)膜病變。Followedbycataract,glaucoma,anddiabeticretinopathy.亞洲低視力病因CausesoflowvisioninAsia亞洲地區(qū)的低視力和盲患病率相對高，白內(nèi)障是最主要的致病原因。TheprevalenceoflowvisionandblindnessisrelativelyhighinAsia,andcataractsistheleadingcauseofthedisease.這與亞洲地區(qū)靠近赤道，緯度較高，接受較多的太陽紫外線的照射有關(guān)系。It’srelatedtothefactthatAsiaisclosertotheequator,withhigherlatitudesandmoreexposuretosolarultravioletradiation.非洲低視力病因Causesoflowvi