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:Toinvestigatethelevelsofserumsolubleintercellularadhesionmolecules-1(sICAM-1)andneutrophilicexpressionofCD18inpatientswithvariousstagesofdiabeticretinopathyandtodeterminetheirdifferentexpressionpatterninthedevelopmentofdiabeticretinopathy(DR).·METHODS:LevelsofserumsICAM-1andCD18onthesurfaceofneutrophileweremeasuredin41DRpatients,theywereclassifiedinthreesubgroupsaccordingtothestageofretinopathyasdeterminedbyfund’sophthalmoscopy;10controlsubjectswerealsostudied.sICAM-1weremeasuredbyenzyme-linkedimmunosorbentassayandCD18byflowcytometry.·RESULTS:TheneutrophilicCD18expressionandserumsICAM-1levelwereallsignificantlyelevatedinalldiabeticsubgroupscomparedtocontrolsubjects(P<0.01).ThedifferencesofCD18andsICAM-1amongthediabeticsubgroupsweresignificantinCD18butnotinsICAM-1.TheprogressionofretinopathywasassociatedwithanincreasebothinCD18andinsICAM-1levelsbysimplecorrelationanalysis(β=0.74,P<0.001;β=0.38,P<0.01,respectively).ButstepwisemultipleregressionanalysisrevealedthatonlyCD18wasindependentdeterminantofretinopathy(β=1.04,P<0.01).·CONCLUSION:OurresultsconfirmthecontributionofendothelialandneutrophilicactivationinthedevelopmentofDRasindicatedbyincreasedlevelsofCD18andsICAM-1.However,adirectimplicationofCD18andICAM-1intheprogressionofDRcanbesupportedonlyintheCD18butnotICAM-1.CD18andICAM-1mayplaydifferentroleinthedevelopmentofdiabeticretinopathy.