眼底图像的三维重建

(,400044),,,,z,,,TP391.41A100125515(2008)0120177205Three2dimensionReconstructionofOcularFundusImageChenJiPengChenglin(CollegeofBioengineering,ChongqingUniversity,Chongqing400044,China)AbstractThemathematicalmodelfor3Dreconstructionofocularfundusimagesisconstructedaccordingtoboththereducedeyemodelandthesimplifiedmodeloffunduscameraopticalsystem.Therelationshipbetweentheimagesofem2metropicandametropiceyeandthetrueshapeofocularfundusretinaisanalyzed,andthenthemappingrelationshipfrom2Docularfundusplanimageto3Dsurfaceimageisobtained.Asaresult,therealexampleof3Dreconstructionforocularfundusimagesisgiven.Themaxvisualfieldofocularfundusimageforthree2dimensionalreconstructionisdecidedbythemaxvisualfieldangleoffunduscamera,whichlimitsasizeofthevisualfieldof3Dreconstructionimageandarangeofzaxis.Accordingtotheformulasof3Dmapping,the2Ddataofocularfundusimageismappedto3Ddataandthenveinsmappingiscarriedout;thereafter,the3Dsurfaceimageofocularfunduscanbedrawnimmediately.Thismethodmakesuseoftheexisting2Dimagingequipmentstoprovide3Dsurfaceimageofpatientsocularfundus,andcanprovideoph2thalmologistwithbeneficialreferenceandhelptotheirclinicaldiagnosisandtreatment.KeywordsOcularfundusimageThree2dimensionreconstructionFunduscameraRetina1,,,,,(CT)(MRI),(Slicebased)(Voxelbased),,BCTMRI,(OCT),25120082JournalofBiomedicalEngineeringVol.25No.1February2008,,Enrique[1],Deguchi[2],,,,[3],(),,,,,,CCD,,CCDCCD,,,,,22.1,,,,,,,,1,,5173mm,,1133,17105mm,22178mm,24113mm[4],H7108mm,12mm,,1Fig1Thereducedeyeandtheequivalentidealopticallensoffunduscamera2.2,CCD,,,,1TOPCONTRC250EX50,1184,26mm22mm,1411mm1/2(614mm418mm)CCD,CCD51176mm,013662.32,O;f;r,H;,[-25,+25]:x2+y2+z2=r2(1)z=rcos(2)[5],87125=+=+arcsin[(f-r)sinr](3),,ABAB,AB(1)(2)z=ctgx2+y2(4)(4)z2Fig2Therelationbetweentheocularfundusimageofemmetropiaandtheretinashapeofocularfundus2.4,24mm,24mm,24mm,,,,z1mm2D[4]3,z=ca1-x2-y2(5):a,c,zz=ymaxtg-k(6),(6)ymax,ymaxz3Fig3Geometricalrelationsoftheocularfundusimageofametropiawiththeretinashapeofocularfundus3,,,:(xi,yi,zi)=f(xi,yi)(7)zi(1),zi(5),(4)(6)z,,450,,,CCD,115G256M49711411845s4(a);(b)(c);(d)(e)Fig4Reconstructionresultfrom2Docularfundusplanimageto3Dsurfaceimage(a)2Docularfundusimage;(b),(c)frontviewof3Dreconstructionimagefromdifferentviewangles;(d),(e)rearviewof3Dreconstructionimagefromdifferentviewangles,257.3%,2414%[5],,,,,,4,,,,,,,,081251EnriqueC,SunandaM,MarkW,etal.Digitalstereoimageana2lyzerforgeneratingautomated32Dmeasuresofopticdiscdeforma2tioninglaucoma.IEEETransactionsonMedicalImageing,2002;21(10)12442DeguchiK,KawamataD,MizutaniK,etal.3Dfundusshapere2constructionanddisplayfromstereofundusimages.IEICETrans2actionsonInformationandSystems,2000;83(7)14083LiC,LiangB,ChenWF,etal.Areconstructionalgorithmofin2verseprojectionfrom2Docularfundusimagesto3Dsurfaceimages.ChineseJournalofBiomedicalEngineering,2002;21(4)346[,,..,2002;21(4)346]4WangYS,LiaoRD,LiuQ,etal.Modernoptometry.Guangzhou:GuangdongScience&TechnoloygPress,2004:25228[,,..:,2004:25228]5DoelemeyerA,PetringBL.Estimationofprojectionerrorsinhu2manocularfundusimaging.OphthalmicPhysiolOpt,2000;20(2)112(:2005208230:2006205215)(176;ContinuedfromPage176)CAD,,,,CAD,,1ToriyabeY,NishimuraT,KitaS,etal.Differentiationbetweenbenignandmetastaticcervicallymphnodeswithultrasound.ClinicalRadiology,1997;52(12)9272AhujaA,YingM.Anoverviewofnecknodesonography.Inves2tigativeRadiology,2002;37(6)3333ZhouYC,GuoWX.Ultrasoundmedicine.Thefourthedition,Bei2jing:ScientificandTechnicalDocumentsPublishingHouse,2003:3632369[,...:.2003:3632369]4RangayyanRM,El2FaramawyNM,LeoJE,etal.Measuresofa2cutanceandshapeforclassificationofbreasttumors.IEEETransac2tionsonMedicalImaging,1997;16(6)7995JudyK,FrancescoP,MartinDF.Classificationmammographicle2sionsusingcomputerizedimageanalysis.IEEETransactionsonMedicalImaging,1993;12(4)6646KimKG,ChoSW,MinSJ,etal.Computerizedschemeforas2sessingultrasonographicfeaturesofbreastmasses.AcademicRadi2ology,2005;12(1)587BrzakovicD,LuoXM,BrzakovicP.Anapproachtoautomatedde2tectionoftumorsinmammograms.IEEETransactionsonMedicalImaging,1990;9(3)233(:2005211202:2006204225)1811