防盲屈光外伤课件

Blindnessandprevention

Refraction

Oculartrauma

防盲治盲-屈光-眼外伤SongYue,MD,PhDProf.ofOphthalmologySTU/CUHKJOINTEYECENTERS防盲屈光外伤Categoriesofvisualimpairment(WHO1977)CategoryofvisualimpairmentVisualacuity视力(Bestcorrected最佳矫正视力)Lowvision1低视力1级Bettereye＜0.3

worseeye≥0.1

Lowvision2低视力2级

0.1

0.05(CF/3m)(指数/3m)Blindness3盲

0.05

0.02(CF/1m)Blindness40.02LP光感Blindness5NLP(无光感)防盲屈光外伤GlobalBlindnessIncidenceofblindness0.7%40-45millionblind90%indevelopingcountries80%blindnessispreventable防盲屈光外伤CausesofBlindnessintheWorld

Cataract白内障46%Trachoma沙眼12.5%Cornealinfection

角膜感染Onchocerciasis(Riverblindness)Xerophthalmia

防盲屈光外伤CausesofBlindnessintheWorld

Glaucoma青光眼Diabetesretinopathy

糖尿病性视网膜病变Trauma外伤Hereditaryconditions遗传Amblyopia弱视Others

防盲屈光外伤BlindnessinChina

Incidenceofblindness0.5%-0.6%Blindpeople:6.70millionLowvision:0.99%-12.00

million防盲屈光外伤CausesofBlindnessinChinaCataract

46.1%Cornealdiseases15.4%Trachoma10.9%Glaucoma8.8%Retinalandchoroidaldiseases5.5%Congenital/Hereditaryconditions5.1%Opticnervediseases2.9%Refractiveerrors/Amblyopia2.9%防盲屈光外伤

PreventionandmanagementofmajorblindingdiseasesCataract

Morethan4millionpeopleinChinaarewaitingforsurgeryThesenumbersareincreasingCataractsurgicalrateislowerinChinaSurgery:Phaco+IOL,ECCE+IOL,ICCE防盲屈光外伤Preventionandmanagementofmajorblindingdiseases

----CornealdiseaseInfectiouscornealdiseasesHSK,BacterialandFungalkeratitisVitAdeficiency:KeratomalaciaMedicaltreatmentandsurgeryCornealtransplantationandcorneadonation,eyebank,etc.防盲屈光外伤Preventionandmanagementofmajorblindingdiseases--TrachomaAformofbilateralkeratoconjunctivitisCausingcornealscaring(blindnessresults)SAFE:surgery,antibiotic,facialcleanliness,andenvironmentalimprovement防盲屈光外伤Preventionandmanagementofmajorblindingdiseases--GlaucomaScreeningEarlyTreatmentMedicaltreatmentand/orsurgery防盲屈光外伤Preventionandmanagementofmajorblindingdiseases--BlindnessinChildrenKeratomalacia(avitaminosisA)

NewbornconjunctivitisCongenitalorhereditaryeyediseasesRetrolentalfibroplasiaTrauma

防盲屈光外伤RehabilitationoftheBlindMobilitytrainingSelf-careHomecareEducationassessmentJobrehabilitationPsychologiccounselingSeeing–eyedog(guidedog)Publicfacilities防盲屈光外伤RehabilitationoftheLowVisionLowvisionaid(低视力助视器)TelescopiceyewearElectronicdevicesSeeing-eyedogSurgery防盲屈光外伤Optometry&

Visionsciences视光学与视觉科学防盲屈光外伤视光学:是一门专业视光师:提供眼保健的专业人士,对眼病进行检查、眼镜验配诊断和视觉系统的康复防盲屈光外伤KeypointsAccommodationandRefraction调节与屈光Refractionsofeyesandametropia屈光不正Diagnosisandcorrectionofametropia屈光不正的矫正防盲屈光外伤Review--Anatomy&Optics

Theeyeisaphotoreceptorwhichhasthecapacitytodetect:lightintensity光强度

lightquality光质量Imageformationresultsfromlightfallingontheretinainadistinctpattern.防盲屈光外伤VisionProcess

视觉传导过程Opticaxis(视轴)角膜—晶体—视网膜（锥杆细胞）-视神经—大脑大脑中形成倒像防盲屈光外伤视觉防盲屈光外伤影象的形成防盲屈光外伤FocalLengthandLensStrength

Themostimportantcharacteristicofalensisitsprincipalfocallength,oritsinversewhichiscalledthelensstrengthorlens“power”.Optometristsusuallyprescribecorrectivelensesintermsofthelenspowerindiopters.Thelenspoweristheinverseofthefocallengthinmeters:thephysicalunitforlenspoweris1/meterwhichiscalleddiopter(屈光度).

主焦距的倒数=屈光度防盲屈光外伤RefractionandtheEye

Refraction

(屈光)isthephenomenonwhichmakesimageformationpossiblebytheeye.cornea-80%

Crystallinelens-20%oftherefractionlensisthetotalsourceoftheabilitytoaccommodate(调节)thefocusoftheeyeCommoneyedefects--“refractiveerrors”(屈光不正)canusuallybecorrectedbyrelativelysimplecompensatinglenses.Emmertropia正视眼Myopia近视眼Hyperopia远视眼防盲屈光外伤Scalemodelofhumaneye

标准眼

防盲屈光外伤Refractionmediaoftheeyes

屈光间质

--TheCornea角膜

Thecornearepresentsthestrongestpartoftherefractingpoweroftheeye,providingabout80%ofthepowerofthesystem.

角膜的屈光力最强防盲屈光外伤CrystallineLens

晶体About9mmindiameterand4mmthick,provides20%oftherefractingpoweroftheeye.

agradientindexlens.Itispliable(柔韧),andchangesshapetoaccomplishaccommodationforclosefocusing.晶体有调节/改变屈光力的作用防盲屈光外伤AqueousHumor

房水Theanteriorchamberoftheeyeisfilledwiththewatery"aqueoushumor"whichhasanindexofrefraction

(屈光指数)ofabout1.336.Itispositionedimmediatelybehindthecornea.防盲屈光外伤VitreousHumor

玻璃体

Thelargechamberoftheeyeisfilledwiththegelatinous"vitreoushumor",whichhasanindexofrefractionofabout1.337.防盲屈光外伤CiliaryMuscleandFibers

睫状肌与肌纤维

Whentheciliarymuscles(睫状肌)contract,theyloosentheciliaryfiberswhichareattachedtotheenvelopeofthecrystallinelens.Becausethelensispliable,itrelaxesintoamorecurvesshape,increasingit‘srefractivepower(屈光力)toaccommodateforcloserviewing.CMContract--CFloosenlens–lensround—refractivepower看近防盲屈光外伤REFRACTION屈光Deflectionorbendingoflightraysresultswhenlightpassesthroughsubstancesofvaryingdensitiesintheeye(cornea,aqueoushumor,lens,andvitreoushumor).Thedeflection(偏斜)oflightintheeyeisreferredtoas

refraction.

光线眼屈光间质发生的偏斜—屈光防盲屈光外伤Accommodation调节Adjustmentoftheeyeforseeingatdifferentdistances,accomplishedbycontractionorrelaxationofthemusclesthatchangetheshapeofthelens,accompaniedbychangesinthepupilsize.眼睛看不同距离物体时睫状肌与肌纤维

的收缩或松弛而导致晶体形态的变化

—调节防盲屈光外伤ACCOMMODATION调节twooptions1.Canchangethedistancebetweenlensandretina2.Canincreasethefocusingpowerofthelens.a)changingdensityisnoteasyb)changeradiusofcurvature防盲屈光外伤AccommodationWhentheeyeisrelaxedandtheinteriorlensistheleastrounded,thelenshasitsmaximumfocallengthfordistantviewing.Asthemuscletensionaroundtheringofmuscleisincreasedandthesupportingfibersaretherebyloosened,theinteriorlensroundsouttoitsminimumfocallength..

Mechanisms防盲屈光外伤AgingoftheaccommodativemechanismStrenkandcolleagues/(MRI)/aginghumaneyes.

Withincreasingage,theunaccommodatedlensthicknessincreases,thelensequatorialdiameterremainsconstant,andtheciliaryringdiameterdecreases.Thisresultsuggeststhatthecircumlentalspacemustdecreasewithincreasingage,butitisnotduetoincreasedequatorialgrowthofthecrystallinelens.ThisfindingisinaccordancewithhistologicstudiesconductedbyTammetal,whichshowaconfigurationalchangeinthehumanciliarymuscle年龄导致睫状肌收缩能力下降，看近困难—老视防盲屈光外伤Accommodationandconvergence

调节与集合集合Convergence:注视近处物体时双眼注视近点而发生内转的现象目的:双眼单视防盲屈光外伤Convergenceofeyes

--Singlebinocularvision

被注视物体距离越近,需要保持单视的集合程度越强Whenantagonisticextrinsicmusclesbalancebroken:diplopia复视Deviationofthevisualaxes:heterophoria.斜视

(Esophoria

内斜视/

exophoria外斜视)防盲屈光外伤NORMALCONDITIONSOFEYEExampleofaccommodationversesnoaccommodation:

-注视远距离物体---不需调节注视近距离物体---需动用调节防盲屈光外伤Ametropia屈光不正

(Errorofrefraction)

Condition:

无调节(松弛)状态下不能聚焦到视网膜中心凹的眼屈光状态--屈光不正Result:Theparallellightpassingthroughtheocularrefractivesystemwiththefocusingoutsidethefovea.防盲屈光外伤Ametropia=

CommonVisionDefects屈光不正3basictypes远视近视散光防盲屈光外伤Myopia近视眼Refractiveerrorinwhichthefocalpointforlightraysfromadistantobjectisanteriortotheretinawhenaccommodationisatrest.

无条件下光线的焦点落于视网膜前原因:Eyeballistoolongorlensistoostrong

眼轴过长或晶体屈光力过强-farsourcesfocusedinfrontoftheretina-nearsourcesarefocusedontheretinawithoutaccommodation-needadivergent(concave凹面镜)lensinfrontoftheeyetocorrectforthis矫正方法:凹面镜防盲屈光外伤防盲屈光外伤ClassificationofMyopia

Functionally: SimpleM.单纯性

PathologicalM.病理性Severityofrefraction:

低度MildM.<-3D

中度ModerateM.-3D~-6D

高度HighM.>-6DRefraction: AxialM.轴性

RefractiveM.屈光性Accommodativefatigue调节疲劳防盲屈光外伤Pathogenesis—RiskfactorsGeneticsDevelopmentEyecare—accommodativespasmOthers防盲屈光外伤ClinicalsymptomsandsignsVisualfunctionchanges:

Visualacuity视力:Poor Visualsensitivity视敏度:decreased Physiologicalblindspot生理盲点:enlarged Peropheralvisualfield周边视野:restricted·Visualfatigue视疲劳: Eyepain&headache,dryeyesensation,防盲屈光外伤symptomsandsignsStrabismus:

(intermittent)exotropia

(间歇性外斜视)

(Duetoimbalancedaccommodationandconvergence集合)Configurationofeyeballs:elongatedlongitudinalocularaxis防盲屈光外伤Funduschangesinmyopia

—并发症Axialmyopia轴性近视:TheprevalenceofmyopiaisdramaticallyhigherinmanyAsianraces,JewishandArabicpeople,andalsotendstobemoresevere.Thereasonsforthisarenotknown,withbothgeneticandenvironmentalfactorsbeingsuggested防盲屈光外伤Pathologicalmyopia2%intheUSA.9%ofblindnessinCanada.China:20%primaryschool;30%inmiddleschool;70%inhighschool.(40%mean)PathologicalM.>6dioptresaxiallength>26-27mm.Itisaprogressive:视网膜脉络膜变性chorioretinaldegeneration,后巩膜葡萄肿posteriorstaphyloma,视网膜脱离retinaldetachment,原发性开角性青光眼primaryopenangleglaucomaand后囊或皮质性白内障posteriorsubcapsularandnuclearcataract.Associatedconditions:retinitispigmentosa,ocularalbinism,infantileglaucoma,retinopathyofprematurity,Down’ssyndrome,Marfan’ssyndrome,Ehlers-DanlossyndromeandSticklerssyndrome防盲屈光外伤TherapyforametropiaClassicalophthalmicspectaclesProgressivemulti-focuslenses(PML)SurgeriesFutureperspectives防盲屈光外伤CorrectionofmyopiaGlasses—classicalContactlens—popularRefractiveSurgeries— RK—Radialkeratectomy PRK—Photorefractive

keratectomy LASIK—LaserInSitu

keratectomy LASEK ICL－－Intrastroma

cornealring防盲屈光外伤1.PhakicAnteriorchamberIOL有晶状体眼人工晶体植入原理：在前房置入人工晶体，以矫正屈光不正

优点：尤其适用于-10.0D以上近视，无明显散光，视力良好，可逆，角膜完整

缺点：光晕、晶体偏位，可能影响角膜内皮或晶状体，远期效果未定

内眼屈光手术2.PhakicPosteriorchamberIOL晶体前接触镜（ICL）

原理：在虹膜和晶状体之间置入人工晶体，以其屈光力矫正近视

优点：尤其适用于-10.0D以上近视，无明显散光，视力良好，角膜完整

缺点：可能损伤晶状体，远期效果未定3.Clearlensextraction

透明晶状体摘除或白内障摘除联合人工晶体植入原理：摘除白内障或透明晶状体，植入屈光力合适的人工晶体以达到矫正近视的目的

优点：适用于伴有晶状体浑浊者，适用于40岁以上-15.00D近视,角膜完整，成像质量好，裸眼视力良好

缺点：调节丧失、有眼内手术的共同危险防盲屈光外伤Correctionofmyopia防盲屈光外伤近视眼眼镜处方原则最佳矫正视力的最低负镜双眼BCVA要平衡Rightcriteriaforgoodapairofglasses:Comfortable,persistent&clear防盲屈光外伤Cycloplegicrefraction

睫状肌麻痹验光Acycloplegicrefractionistheprocedurewherebyanindividual'srefractiveerrorisdeterminedwhilethemusclesthatcontrolaccommodationareparalyzedwithdilatingagents.Childrenundertheageof10yearshaveimmenseaccommodativepowers,andthismustbecontrolledinorderfortheexaminertoproperlydeterminetherefractiveerror,orneedforcorrection.Cycloplegiaiscompletedwitheyedropmedications.Thetechniqueofretinoscopy:todeterminethechild'srefractiveerror,ifanyispresent.防盲屈光外伤Hyperopia

远视眼

Hypermetrophia(farsightedness)

Thefocalpointforlightraysfromadistantobjectisposteriortotheretinawhenaccommodationisatrest.Eyeballistooshortorlensistooweak -Farsoucefocusedonretinawithaccommodation -NearsourcefocusedbehindretinaevenwithaccommodationUseaconvexlens,needingaccommodationfornearobjects防盲屈光外伤ClassificationAxialH.RefractiveH.MildH:<+3.00DModerateH.:+3.00D~+6.00DHighH.:+6.00D防盲屈光外伤Symptoms&signsVisualacuity:Yongandmild—Accommodation—goodvisionAccommodativespam--myopicVisualfatigue:Poorfornearreading(Agingeffect)Strabismus:esotropia,ambliopia(uncorrectedhighH.)PathologicalchangesPooropticdiskdevelopmentshallowACcausingHighGlaucomaincidence防盲屈光外伤Correctionofhyperopia原位角膜磨镶术（LASIK）激光角膜热成形术（LTK）

防盲屈光外伤AstigmatismThecurvatureoftheopticalsystemvariesindifferentmeridiansthusrefractingtheincidentlightdifferentlyinthosemeridians.光学系统的曲率在不同经线上不同,因此不同经线的屈光力不同散光

防盲屈光外伤Types

Withtheruleastigmatism:theverticalmeridianissteeper

顺规散光Against-the-ruleastigmatism:thehorizontalmeridianissteeper

逆规散光Regularastigmatism:Principlemeridiansare90degreesapart规则散光Irregularastigmatism:Principlemeridiansarenot90degreesapart.不规则散光

Thistypeofastigmatismcannotbecompletelycorrectedbyspectaclesandmayneedcontactlenses.(Suitableforrefractivesurgeries)防盲屈光外伤Symptomsof

astigmatism:

Blurredvisionforfarandnear远近视力均模糊Squint(forpinholeeffect)AsthenopicsymptomsFrontalheadachesTiltingofthehead(forobliqueastigmatism)防盲屈光外伤Treatmentiswithcylindricallenses.防盲屈光外伤Presbyopia

老视眼\老花眼"Oldsight"Nota"disease"-explaintopatientsDistancevision?AgeofonsetDependsonindividuals,ace,occupation,andhabitsSymptomsofpresbyopia"Ihavetoholdmybookfurtheraway""myarmsarenotlongenough""newspaperprintisnotwhatitusedtobe"Patientscomplainofreadingdifficultyinpoorlight,tiredeyesafterreadingandBLURREDVISIONforreading防盲屈光外伤Presbyopia

Itisthephysiologicdecreaseintheamplitudeofaccomodationassociatedwithaging.Thereislessbulgingofthelenswithaccomodationduetoachangeinthecrystallinsofthelensthatresultindecreaseintheelasticityofthelensfibersorhardeningofthelens.Symptomsinclude:-largerreadingdistancerequired-inabilitytofocusonclosework.-Excessiveilluminationrequiredforclosework.Treatment:Addpositivelensestofarcorrectionaccordingtoage.防盲屈光外伤PresbyopiaManagementPrescribecorrectionsothatnearpointoffocusisbroughtwithinnormalworkingdistanceDeterminationofreadingadditionObjective-dynamicretinoscopySubjective- (a)completedistancerefraction(b)measureamplitudesofaccommodation(c)useamplitudesasaSTARTINGpointtocalculateanapproximatereadingadditionRuleofthumb-leave1/3rdaccommodationinreserveCheckclarityandrange.Doublecheckwith+&-additions防盲屈光外伤ResearchandpreventionMyopia:1.Animalmodels:

Formdeprivationmodel(形觉剥夺性近视)

Opticaldefocusmyopia(光学离焦近视)２.ExperimentalM.—Axis３.Growthfactorandbiochemicals４.Genetics:Pax6genePresbyopia:Lensandciliarymuscles防盲屈光外伤Oculartrauma

眼外伤防盲屈光外伤国际眼外伤分类闭合性眼外伤开放性眼外伤眼挫伤板层裂伤撕裂伤破裂伤穿通伤球内异物伤穿孔伤防盲屈光外伤Periorbitalecchymosis淤血

Commonlyknownasa"blackeye,"isbloodaccumulationintheeyelids.Itisusuallymorenoticeableinthelowerlidandoccasionallyformsanorganizedhematomaorfirmpurplish-blackmass.眶周皮下淤血防盲屈光外伤Retrobulbarhemorrhage

球后出血眶内血管破裂眶压升高压迫视神经原因顿挫伤球后出血防盲屈光外伤Eyelidlacerations

眼睑撕裂伤CanoccurfromtraumaTotreatsimple,superficiallacerations,cleanthewoundandsurroundingskin(e.g.withBetadine),irrigateitthoroughlywithsaline,andremoveanyforeignmaterialthatmaystillbepresent.Thenapplyanantibacterialointmentandsteriledressing.眼睑裂伤防盲屈光外伤SubconjunctivalhemorrhagesTypicallydonotrequiretreatment,althoughartificialtearstendtoenhancecomfortforpatientswhoaresymptomatic.结膜下出血防盲屈光外伤CornealandconjunctivalforeignbodiesPatientscanbecompletelyasymptomatic,butgenerallyforeignbodiescausemildtomoderateeyepaindependingontheircomposition,location,andthepatient'spaintolerance.Whenexaminingapatientwithapossibleforeignbody,itisalwaysimportanttoinspectthefornicesthoroughlyandeverttheeyelidstolookforoccultpalpebralconjunctivalforeignbodies,whichcancausecornealtrackmarks.角膜与结膜异物防盲屈光外伤防盲屈光外伤Chemicalburns

眼化学伤损伤眼组织严重,可以导致失明Worrisome,becauseoftheirabilitytoprofoundlyaffectmultipleocularstructuresandpotentiallycauseblindness.碱的损伤最可怕:亲水、亲脂、穿透力强Alkalineagentsareparticularlydamagingbecausetheyarebothhydrophilicandlipophilicandcanrapidlypenetratecellmembranes.Penetrationoftheanteriorchamberisevenpossible.细胞膜的皂化细胞外间质的破坏和细胞死亡产生的毒素是损伤眼组织的主要因素Oculardamageresultsfromsaponificationofcellmembranesandcelldeathalongwithdisruptionoftheextracellularmatrix.化学烧伤防盲屈光外伤Burn—Alklineandacid碱酸防盲屈光外伤Hyphema前房出血

&Hemosiderosis角膜血染

HyphemaislayeringofRBCsintheinferioranteriorchamber.Duringtheslit-lampexamination,itisoftheutmostimportancetomeasurethehyphemaheightinmillimeters,becausethiswilldictateboththemanagementandfollow-upofthecondition.Hemosiderosisistheclinicalentityinwhichthecorneabecomesstainedbyblood;specificallybytheironcontainedwithintheRBCs.前房出血角膜血染防盲屈光外伤Contusions

挫伤Traumaticiritispresentsverymuchlikeothertypesofanterioruveitides,howeverahistoryoftraumaiscriticalinmakingacorrectdiagnosis.Theretendstobephotophobiainboththeinvolvedandtheuninvolvedeye(becauseofconsensualpupillaryconstriction),perilimbalinjection,andcellsandflareintheanteriorchamber.Anglerecessionisoftenoverlookedongonioscopy,butitoccurscommonlywithbluntoculartrauma.Traumaticglaucomaisasecondaryopen-angleglaucomathatmayoccurin2-10%ofthosewithanglerecessionwithina10yearperiod.Itismorelikelytooccurwith180°ormoreofanglerecession.Iridodialysisisadetachmentoftheirisrootfromtheciliarybodyandcanproducecorectopia(irregularpupilshape),pseudopolycoria,anddiplopia.外伤性虹膜炎房角后退虹膜根离断防盲屈光外伤Contusions

挫伤Traumaticcataract,orcontusionrosette,maynotbeapparentuntilyearsafteratrauma.Althoughanteriorand/orposteriorsubcapsularopacitiescanoccurwithtrauma,apetalliformcataractwithacompactwhitestar-shapedopacity,usuallyintheanteriorcortex,ismostcommonlyfound.外伤性白内障防盲屈光外伤ContusionsLenssubluxationisapartiallydislocatedcrystallinelenscausedbyincompletezonulardehiscencesecondarytoequatorialexpansionoftheglobefromtrauma.Althoughavisiblelensequator(sometimeswithvisiblezonules)isthehallmarkofthiscondition,iridodonesisand/orphakodonesis(i.e.,quiveringoftheirisandlenswitheyemovements,respectively)arecommonlypresent.Lensdislocationiscausedbycompletezonulardehiscence.Thedislocatedlenscanbepositionedeitherintheposteriorsegmentortheanteriorchamber.晶体半脱位晶体脱位防盲屈光外伤Pre-retinalhemorrhageisconfinedbetweenthenervefiberlayerandtheinternallimitingmembraneoftheretinaandisoftenassociatedwithachoroidalrupture.Thevisualacuitycanbeseverelyreducedifitliesinfrontofthemacula.Choroidalruptureisdetectableasayelloworwhitecrescent-shapedsubretinalstreakthatisoftenconcentricwiththeopticnerve.视网膜前出血脉络膜破裂防盲屈光外伤Traumaticmacularholeisclinicallysimilartotheidiopathicvarietyinappearance.Itpresentsasaround,redspotinthecenterofthemaculawithorwithoutasurroundingcuffofedemathatcanlooklikeagreyhalo.外伤性黄斑裂孔防盲屈光外伤Purtscher'sretinopathyisaninterestingclinicalconditionthatoccursafteraninjurythatincludeseithermajorchestcompressionorheadtrauma.Classically,thepatientpresentswithcotton-woolspotsandhemorrhagesalongtheretinalarcades,sothisdiagnosisisdrivenfirstbyhistoryandthenbytheclinicalpresentation.Purtscher‘s斑防盲屈光外伤Openglobeoculartrauma

开放性眼外伤Globeruptureisoneofthemostghastlyconsequencesofoculartraumaandmustalwaysbeconsideredwhenevaluatingapatientwhohassustainedblunttraumaoralaceratinginjury.眼球破裂伤防盲屈光外伤Penetration穿透伤防盲屈光外伤CorneallacerationPatientstypicallyhaveahistoryinvolvingcuttingortearingthecornea.角膜裂伤防盲屈光外伤Intraorbitalforeignbody(IOrbFB)shouldbeconsideredforallhigh-velocityperiocularinjuries.WithinorganicIOrbFBs,visionlossisusuallyduetotheinitia