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Ocular Higher-Order Aberrations and Mesopic Pupil Size in Individuals

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Ocular Higher-Order Aberrations and Mesopic Pupil Size in Individuals HOAsandpupilsizeinindividuals 窑ClinicalResearch窑 Ocularhigher-orderaberrationsandmesopicpupil sizeinindividualsscreenedforrefractivesurgery 1EyeResearchcenter,RasoulAkramHospitalTehran hyperopescomparedtomyopes.Mesopicpupilsizewas UniversityofMedicalSciences,Tehran,Iran largerinmyopicgroup. 2DepartmentofEpidemiologyandBiostatistics,Schoolof ·KEYWORDS:cornealwavefrontaberration;pupil;mesopic PublicHealth,TehranUniversityofMedicalSciences, vision;race;myopia;hyperopia Tehran,Iran DOI:10.3980/j.issn.2222-3959.2012.02.21 Correspondenceto: MohammadSoleimani.EyeResearch Center,RassoulAkramHospital,TehranUniversityof HashemianSJ,SoleimaniM,ForoutanA,JoshaghaniM,Ghaempanah MedicalSciences,Tehran,[email protected] MJ,JafariME,YaseriM.Ocularhigher-orderaberrationsand Received:2011-08-23Accepted:2012-03-10 mesopicpupilsizeinindividualsscreenedforrefractivesurgery. 2012;5(2):222-225 Abstract INTRODUCTION AIM:Tostudythedistributionofocularhigher-order · cularaberrationsmayplayamajorroleintheimage aberrations(HOAs)andmesopicpupilsizeinindividuals O formationintheocularopticalsystem.Lowerorder screenedforrefractivesurgery. aberrationssuchasastigmatismanddefocuscaneasilybe · METHODS:OcularHOAsandmesopicpupilsizewere correctedandmaybelessproblematic,howeverhigher studiedin2458eyesof1240patientswithmyopia,myopic orderaberrations(HOAs)cancausemoredegradationofthe astigmatismandcompoundmyopicastigmatismand215eyes visualperformance[1-5]. of110patientswithhyperopia,hyperopicastigmatismand Customizedcornealablationhasbeensuccessfullyusedto compoundhyperopic astigmatismusingtheZywave addresswavefrontaberrationsoftheeye.Givenincreasing aberrometer(Busch&Lomb).Allpatientshadcorrectable interestinthemanagementofocularaberrations,performing refractiveerrorswithoutahistoryofrefractivesurgeryor preoperativeaberrometryismoreusualthanthepast.Higher underlyingdiseases.Root-mean-squarevaluesofHOAs,total orderaberrationscannotbecorrectedbysphero-cylindric sphericalaberration,totalcomaandmesopicpupilsizewere lenseswhichmakethemveryimportantinclinicalpractice. analyzed.OcularHOAsweremeasuredacrossa≥ 6.0mm Thepupilsizecanaffecttheresultsofrefractivesurgeries pupil,andpupilsizemeasurementswereperformedunder duetoitsroleinpostoperativevisualsymptomssuchas themesopiccondition. glareandhalo.Thelargerpupilsizemayalsoproduce · RESULTS:ThemeanvaluesofHOAs,totalspherical greaterHOAs [1,4].Thusthepupildiameterisanimportant aberrationandtotalcomainthemyopicgroupwere0.369 m, factortoconsiderespeciallyforthosepatientswhoare 滋 ± 0.233,0.133± 0.112 mand0.330± 0.188 m,respectively. candidatesforrefractivesurgery. 滋 滋 InthehyperopicgroupthemeanvaluesofHOAs,total InthisstudyweinvestigatedthedistributionofHOAsand sphericalaberrationandtotalcomawere0.418 m ± 0.214, mesopicpupilsize(MPS)inindividualsscreenedfor 滋 0.202± 0.209 mand0.343± 0.201 m,respectively.Hyperopes refractivesurgery. 滋 滋 showedgreatertotalHOAs(<0.01)andtotalspherical MATERIALSANDMETHODS aberration(<0.01)comparedtomyopes.Inage-matched Materials Totally2458eyesof1240patientswithmyopia, analysis,onlytheamountoftotalsphericalaberrationwas myopicastigmatismandcompoundmyopicastigmatismand higherinthehyperopicgroup( =0.05).Mesopicpupilsizein 215 eyesof110patientswithhyperopia,hyperopic themyopicgroupwaslarger( 0.05). 臆 astigmatismandcompoundhyperopicastigmatismwere ·CONCLUSION:Theresultssuggestedthatsignificantlevels enrolledinourstudy.Subjectswereselectedfrompatients ofHOAswerefoundinbothgroupswhichareimportantfor referredforrefractivesurgerytoourcenterfromSeptember planningrefractivesurgeriesonIranians.Therewere 2006toNovember2008whoparticipatedinacross significantlyhigherlevelsoftotalsphericalaberrationin sectionalstudy. 222 陨灶贼允韵责澡贼澡葬造皂燥造熏灾燥造援 5熏晕燥援 2熏 Apr.18, 圆园12 www.IJO.cn 栽藻造押8629原愿圆圆源缘员苑圆 8629-83085628 耘皂葬蚤造押ijopress岳员远猿援糟燥皂 Methods Table 1 Patient demography Myopia Hyperopia Wavefrontaberrometry Thepresentstudyusedthe Number 2458 eyes of 1240 215 eyes of 110 ZywaveaberrometerdevelopedbyBusch&Lombbasedon patients patients Mean±SD -3.76±2.94 +3.26±2.57 theHartmann-Shackprinciple.Allwavefrontmeasurements Refraction Range -16.00 to -0.75 +0.50 to +8.25D wereperformedbythesameexaminer. Mean±SD -1.24±1.75 -1.56±1.87 Cylinder Allwavefrontmeasurementswererepeated3timesforeach Range -7.00 to 0.0 -6.80 to 0.0 Mean±SD 28.3±7.32 37.69±10.09 Age eye.Thebestimagewasincludedinthestudybasedonthe Range 18 to 56 20 to 64 imagequality.Ifthewavefrontrefractionofthepatientwas 70% (1707) 60% (128) Gender consistentwiththesubjectiverefraction(differences 30% (741) 40% (85) betweensphericaldiopter: 0.75D,cylindricaldiopter: T able 2 Refractive error, higher order aberration and mesopic pupil size 依 0.5Dandastigmaticaxis: 15° ),itwouldbeincludedin Myopia Hyperopia P 依 依 Mean±SD 6.17±1.35 5.60±1.30 thestudyandthenHOAsandrootmeansquare(RMS) Mesopic pupil size <0.01 Range 2.8 to 8.9 2.8 to 8.0 values weredocumented.Atfirstweperformed * Mean±SD 0.37±0.23 0.42±0.21 Ho-RMS <0.01 2 Range 0.10 to 0.99 0.16 to 0.97 pupillometryundermesopiccondition(5cd/m )andthena Mean±SD 0.33±0.19 0.34±0.20 Total Coma 0.48 pupillarydiameterofatleast6.0mmusingtropicamide0.5% Range 0.08 to 0.96 0.13 to 0.95 Mean±SD 0.13±0.11 0.20±0.21 Total spherical aberration <0.01 eyedropwasusedfortheanalysisinthisstudy. Range 0.0 to 0.65 0.0 to 0.56 Allpatientswereexaminedtoexcludeothercontributing *Ho-RMS: Higher order RMS. factorssuchaspreviousocularorcornealdiseases,cataract, cornealscarorothermediaopacitiesandsurgeryortrauma whichcouldalterwavefrontmeasurements.Patientswitha best-correctedvisualacuity(BCVA)oflessthan20/40were excluded. StatisticalAnalysis RMSvaluesofHOAsandMPSwere analyzed.DatawereanalyzedusingtheStatisticalProgram forSocialSciences(SPSS)(Version15,SPSSInc.,Chicago, Illinois,USA).Toevaluatenormaldistributionof quantitativedata,weemployedKolmogorov-Smirnovtest. Basedonthistest,weusedT-testtocomparemyopicand Figure1Higherorderaberrationsandrefractiveerror TC: hyperopicsubjectsafterthedesigneffectofbilateralcases totalcoma;TSA:totalsphericalaberration. hadbeenadjusted.Pvaluesofequalorlessthan0.05were consideredtobestatisticallysignificant. higherinhyperopiceyes( =0.05).Themajorityofhigher RESULTS orderaberrationswererelatedtothethirdandfourthorder Myopicsphericalequivalent(SE)wasintherangeof-0.75 aberrations(Figure1,Table2). to-16.0Dwithamean SDof-3.76D 2.94andacylinderof DISCUSSION 依 依 -1.24D 1.75.Inthehyperopicgrouphyperopicspherical Inthisstudy,weinvestigatedocularHOAsandMPSinboth 依 equivalent(SE)wasintherangeof+0.50to+8.25Dwitha myopicandhyperopicpatients.Aberrometryisavaluable mean SDof+3.26D 2.57andacylinderof-1.56D 1.87. methodtodetecteyeswithanabnormalopticalcondition. 依 依 依 Themeanagewas28.31 7.32and37.69 10.09formyopic Consistentwithpreviousstudies,ocularwavefrontaberrations 依 依 andhyperopicpatients,respectively(Table1). differedwidelybetweensubjects,withameanSDof ThemeanMPSinmyopicgroupwas6.17mm 1.35mm approximately0.10 mforthetotalHOAs.Themeantotal 依 滋 [6-10] (range:2.80mmto8.90mm),andinhyperopicgroupwas higher-orderRMSvalueis0.33 mfora6.0-mmpupil . 滋 5.60mm 1.30mm(range:2.80mmto8.00mm).MPSwas RMSvaluescanbecalculatedfromaberrationcoefficients 依 largerinmyopicpatients( <0.01,Table2). andrepresentasummaryofopticalquality.Inthepresent ThemeanvalueofHOAsinmyopicgroupwas0.369 m study,HOAsinmyopicpatients(average:0.369 m)were 滋 依 滋 0.233(range0.100 mto0.990 m).Themeantotal lowerthanthoseinhyperopicpatients(average:0.418 m). 滋 滋 滋 sphericalaberration(TSA)was0.133 0.112 mandthe Thismightbebecauseoftheconfoundingroleoftheagein 依 滋 meantotalcomawas(TC)0.330 0.188 minthisgroup.In ourstudy,sincethemeanageofhyperopicsubjectswas 依 滋 hyperopicgroupthemeanvalueofHOAswas0.418 m significantlyhigherthanmyopicsubjectsandasother 滋 依 [11-14] 0.214(range:0.160 mto0.970 m).ThemeanTSAwas studieshaveshownHOAsincreasewithage .In 滋 滋 0.202 0.209 mandthemeanTCwas0.343 0.201 mfor age-matchedanalysis,onlyTSAwashigherinhyperopic 依 滋 依 滋 [15] hyperopicgroup.Comparedtomyopicpatients,hyperopic patients.Liorente alsohavereportedgreater patientshadsignificantlyhighertotalHOAsandTSAs(< sphericalaberrationinhyperopiacomparedtomyopia. 0.01)inbothcases.Inage-matchedanalysis,onlyTSAwas Bisneto [16] suggestedthathyperopicpatientswithless 223 HOAsandpupilsizeinindividuals than-0.75Dastigmatismshowgreateramountofspherical inmyopicgroup.Hashemi .reportedaninverse aberrationandhyperopicpatientswithmorethan-0.75D relationshipbetweenrefractiveerrorandpupilsizein astigmatismshowagreateramountofotherHOAs(other univariableanalysis,butnotinthemultivariableanalysis, thancomaandsphericalaberration)andalsohigh-order supportedbyotherstudies [43-45].Theyreportedsmallerpupil RMSaberrations. HOAsmaybe morecommon in sizesamonghyperopicpatientscomparedtothemyopes ammetropiceyesthanemmetropiceyes,asHe [17] probablybecauseofmoreaccommodationinhyperopic [46] proposedthatmyopicpatientsmaypresentwithgreater subjects . Howeversomestudieshavereportedno HOAscomparedtoemmetropes.Ontheotherhand,there relationshipbetweenthepupildiameterandrefraction aresomestudiesthatproposenorelationshiporevenan amongpatientswithhyperopiaandmyopia[47,48].Therearenot oppositerelationshipbetweenmyopiaorhyperopiaand anyorganizeddataaboutmesopicpupilsizesindifferent higherorderaberrations[15-21].Kirwan [22] reportedgreater racesanddifferentiriscolors.Kokh [49] reportedthat higherorderaberrationsinmyopescomparedtohyperopes, browniriscolorsmaybeassociatedwithlargerpupilsizes. howevertheystudiedonchildren,apopulationdifferent Schnitzler [50] haveproposedthatthepupildiameterin fromourstudy.In our study, themostsignificant
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