简介：AIM:Todescribethecharacteristicsofmodulationtransferfunction(MTF)ofanteriorcornealsurface,andobtainthethenormalreferencerangeofMTFatdifferentspatialfrequenciesandopticalzonesoftheanteriorcornealsurfaceinmyopes.·METHODS:Fourhundredeyesfrom200patientswereexaminedunderSIRIUScornealtopographysystem.PhoenisanalysissoftwarewasappliedtosimulatetheMTFcurvesofanteriorcornealsurfaceatverticalandhorizontalmeridiansatthe3,4,5,6,7mmopticalzonesofcornea.TheMTFvaluesatspatialfrequenciesof5,10,15,20,25,30,35,40,45,50,55and60cycles/degree(c/d)wereselected.·RESULTS:TheMTFcurveofanteriorcornealsurfacedecreasedrapidlyfromlowtointermediatefrequency(0-15cpd)atvariousopticalzonesofcornea,thevaluedecreasedto0slowlyathigherfrequency(>15cpd).Withtheincreaseoftheopticalzonesofcornea,MTFcurvedecreasedgradually.3)Intherangeof3mm-6mmopticalzonesofthecornea,theMTFvaluesmeasuredathorizontalmeridianweregreaterthanthecorrespondingvaluesathorizontalmeridianofeachspatialfrequency,thedifferencewasstatisticallysignificant(P<0.05).At7mmopticalzonesofcornea,theMTFvaluesmeasuredathorizontalmeridianwerelessthanthecorrespondingvaluesatverticalmeridianat10-60spatialfrequencies(cpd),andthedifferencewasstatisticallysignificantin25,30,35,40,45,50cpd(P<0.05).·CONCLUSION:MTFcanbeusedtodescribetheimagingqualityofopticalsystemsatanteriorcornealsurfaceobjectivelyindetail.

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：AIM:Topresenttheoutcomeofmodifiedgridlaserphotocoagulation(GLP)indiffusediabeticmacularedema(DDME)ineyeswithoutextrafovealand/orvitreofovealtraction.METHODS:InclusioncriteriafortheretrospectivestudywereDDMEeyesofpatientswithtypeⅡdiabetesmellitusthathad≥4monthsoffollow-upfollowingGLP.Onlyoneeyeperpatientwasanalyzed.Using3-Dspectral-domainopticalcoherencetomography(3-DSDOCT),eyesthathadeitherextrafovealorvitreofovealtraction,orhadbeenpreviouslytreatedbyanintravitrealmedication(s)wereexcluded.TreatedDDMEeyesweredividedinto4groups:A)'Classic'DDMEthatinvolvedthecentralmacula;B)edemadidnotinvolvethemacularcenter;C)eyesassociatedwithcentralepiretinalmembrane(ERM);D)DDMEthatwasassociatedwithmacularcapillarydropout≥2disc-diameter(DD).RESULTS:GLPoutcomein35DDMEeyesafter4-24(mean,13.1±6.9)monthswasasfollows:GroupA)18eyeswith'classic'DDME.Followingoneor2(mean,1.2)GLPtreatments,best-correctedvisualacuity(BCVA)improvedby1-2Snellenlinesin44.4%(8/18)ofeyes,andworsenedby1linein11.1%(2/18).Centralmacularthickness(CMT)improvedby7%-49%(mean,26.6%)in77.8%(14/18)ofeyes.CausesofCMTworsening(n=4)werecommonlyexplainable,predominantly(n=3)associatedwithemergenceofextrafovealtraction,5-9monthspost-GLP.GroupB)GLP(s)inDDMEthatdidnotinvolvethemacularcenter(n=6)resultedinimprovedBCVAby1-2linesin2eyes.However,thecentralmaculabecameinvolvedintheedemaprocessaftertheGLPin3(50%)eyes,associatedwithanemergenceofextrafovealtractioninoneoftheseeyes4monthsfollowingtheGLP.GroupC)GLPfailedinall5eyesassociatedwithcentralERM.GroupD)GLPwasofpartialbenefitin2of6treatedeyeswithmacularcapillarydropout≥2DD.CONCLUSION:EyeswithDDMEthatinvolvedthemacularcenterwerefoundtoachievefavourableoutcomesafterGLP(s)duringmid-termfollow-up,unlesscomplicatedpre-GLPorpost-GLPbyvltreoretinalinterfaceabnormalities,oftenextrafovealtra