DTIstudiomannulWord文件下载.docx

DTIstudiomannulWord文件下载.docx

《DTIstudiomannulWord文件下载.docx》由会员分享，可在线阅读，更多相关《DTIstudiomannulWord文件下载.docx（40页珍藏版）》请在冰点文库上搜索。

February,2005

Introduction

DTIStudioisadiffusiontensorimageprocessingprogramrunningunderWindows.Itissuitableforsuchtasksastensorcalculation,colormapping,fibertracking,and3Dvisualization.Mostofoperationscanbedonewithonlyafewclicks.

Toolsintheprogramcanbegroupedinthefollowingway:

∙ImageViewer

∙DiffusionTensorCalculations

∙FiberTrackingandEditing

∙3DVisualization

∙ImageFileManagement

∙RegionofInteresting（ROI）DrawingandStatistics

Launchingtheprogramandhardwarerequirement

DTIStudioisarathersmallprogram,onlyfewhundredskilobytesinsize.Onceyougetthesoftware,youcansimplycopyittoyourcomputerusingWindowsExplore.Althoughyouareallowedtocopyittomultiplecomputers,IrecommendthatyoutoregisterallusersandPIs（principalinvestigators）.Onceyouandyourcolleaguesareregistered,you’llbeincludedinouruserlistandwe’llnotifyyouupgrade,modifications,andbugs.

DiffusionimagedatafilesareusuallyverybigandalargeamountofRAMisneededforitsprocessing.Ifyouexperience“NotEnoughMemory”messagesortheprogramsuddenlyquitsinamiddleofcalculation,theseareduetoRAMshortage.Morethan1GBRAMisrecommended.IfyouhaveacomputerwithalesseramountofRAM,thereisawaytodivide3Dvolumedataintosmallerblocks,performtensorcalculationseparately,andlatercombinethemtorestoretheoriginal3Dvolume.Thisapproach,however,doesn’tworkforfibertracking,whichrequirestheentire3Dvolumeforthecalculation.

Tostarttheprogram,youcansimplydouble-clickaDtiStudioicon.Almostimmediately,thecorrespondingDTIStudiowindowappearslikemostWindows-basedprograms.Atthismoment,youarereadytoplaywiththeprogram.

Imageviewer（Programname:

MRI-View3D）

“File->

MRIview3D”orclick“openfile”icononthetopmenubar

Thisisaversatileviewerprogramforimagedisplay.Thisfunctionislunchedbyclicking"

MRIView3D"

inthe"

File"

menuonthemenubar（Fig.1）.

Figure1.LunchtheMRIViewerbyclickingMRIView3DinFilemenu

Figure2.Specifytheimageparametersusingthedialog

Imageparameterdialogwindow（Fig.2）

Afteryouchooseanimagefile,anewwindowappears（Fig.2）,promptingyoutospecifyimageparameters.

“ImageFileFormat”

MRIview3Dcanrecognizeavariety3Dimagefileformats,includingPhilipspackedfiles（"

.rec"

file）,Siemens/GEDICOMfiles,GE-Signaimagefiles（“Ixxx”files）,aswellasrawimagefiles.DICOMorGEIxxxformatscontainonlyone2Dsliceimageperfile.Usually,multipleimagefilesfromone3Dvolumedataarestoredwithinonedirectory.ForaDTIdataset,adirectorymaycontainimagefilesfrommanydifferentvolumes,eachcorrespondingtoaparticulargradientorientationandb-value.IfyouselectanyoneoftheseDICOMfiles,MRIview3Dreadsallfileswithinthedirectoryandtriestoreconstruct3Dvolumes.Itisimportantnottomixdifferenttypesofimageswithinonedirectory.Forexample,ifadirectorycontainsbothscoutimagesanddiffusionimages,MRIview3Dwouldbeconfusedbecausethetwodatabasehaveadifferentmatrixsize,FOV,andnumberofslices.Itisadvisedtosavedifferentimagingsessionsintodifferentdirectories.

Supposeyouacquired256x256x60volumedatawith12gradientorientationsinadditiontooneb0image.Youshouldhave60x13=780DICOMfileswithinadirectory.YoucanchooseanyfilewithintheDICOMdirectoryandMRIview3Dwillreadall780files.Theprogramwillreconstruct133Dvolumesdatawithadimensionof256x256x60.UsingDtiStudio,youcouldcreateone“concatenated”datasetwithdimensions256x256x780andsaveitasasinglefileusingthe“save”function（whichwillbediscussedlater）.ThisconcatenatedfileformatisactuallyaconvenientwaytostoreDTIdataratherthandealingwith780separateDICOMfileswithencryptedfilenames.DtiStudioandassociatedprogramssometimeshavefunctionsthatwillonlyreadtheseconcatenatedfiletypeswithoutaheader.Ifyouwishtousethesefunctions,nowisthetimetoconvertDICOMfilestotheconcatenatedfile.

Philipsscannershaveafunctiontoexportaconcatenated3Dfile.Thisiscalleda“.rec”file.PleasebewarethatPhilipsusestwomethodstoconcatenatetheimagedatadependingontheversionoftheoperatingsystem.Inolderversions,theorderofthestoredimagesis;

slice#1/b0->

slice#1/gradientorientation#1->

slice#1/gradientorientation#,etc.Inthisinstance,thegradientorientationisincrementedbeforetheslicenumberis（theslicesare“interleaved”）.Inneweroperationsystem,theorderis:

slice#2/b0->

slice#3/b0->

…,inwhichtheslicenumberisincrementedpriortothegradientorientation.Intheformercase,“PhilipsREC（inslices）”needstobeselectedand“PhilipsREC（inblocks）”forthelattercase.IfyouarenotsurewhattheorderofyourPhilipsRECdatais,justtryoneofthem.Youcaneasilychangetheorderlaterusingiconintheprimaryviewingwindow（whichwillbeexplainedlater）.

“ImageDataFormat”

Thissectionspecifiestheformatofthedata.AscanbeseeninFig.2,MRview3Dcanreadmanytypesofimages;

includingbothrawDTIdataandprocessedimagessuchasADC,FA,andcolor-codedmaps.Evenanatomicalscanscanbeloadedforvisualization.Choicesincludebyte,float（e.g.FAmap）,complex（e.g.k-spaceimage）,RGB（e.g.colormap）orXYZ（e.g.eigenvector）dataformats.Ifyouarenotsureaboutthefileformat,justtryoneofthem.Youcaneasilychangetheorderlaterusingicon.

Acompleximagecanbedisplayedinmodulusorphasemode,oronecanchoosetodisplayitsrealorimaginarypartbythemselves.Youcanchoosebetweentheseoptionsinanotherdialogevokedwiththe"

DisplayMode"

button,whichisenabledforthecompleximagedataformat.Analogously,thereareseveraldisplaymodesforavectorimagethatcanalsobeselectedviathe“DisplayMode”button.

“ImageOffset”

Thebeginningofarawimagefilemaycontainaheader.The"

imageoffset"

editorcanbeusedtoviewtheseimagescorrectly.Theoffsetcouldbeindicatedinbytes,pixelsornumberofimage-rows.

“SwapDataBytesOrder”

ThisproblemarisesbecausethebinarydataordercanbeorderedintwodifferentwaysundertheIEEEstandard.Theso-called"

big-endian"

orhigh-byteIEEEformatisfoundinSGI,SUN,IBMRS6000,andallMotorolachip-basedsystems.The"

little-endian"

orlow-bytesystemsaresystemsthatarebasedonIntelandDecchips.

DTIStudioisdevelopedontheIntel-chips-basedWindowsplatform,soifyoutransportrawdatafromnon-Intelbasedplatforms（e.g.fromaSun-workstation）,youmayhavetoswapthebytestoloadtheimagedatacorrectly.

“SliceOrientationandSliceSequencing”

Theseselections（andfieldofviewandslicethickness）haveanimpactonimagedisplay.Accordingtothisinformation,theprogramcandisplayandarrangetheimagescorrectlyinthreeorthogonalviews.

PrimaryImageViewWindow（Fig.3）

3Dview

Axialview

Coronalview

Sagittalview

Control-Panelview

Figure3.Imageviewwindowforthreeorthogonalviews,a3Dview,andacontrol-panel.

Imageviewingsection

Ifadatasetissuccessfullyloaded,theprogramreconstructsall3Dimageobjectsincludedinanimagefile（concatenatedfile）orinadirectory（DICOMfile）,createsaprimaryimageviewwindow,anddisplaysthefirstimageobject.TheprimaryimageviewwindowisshowninFig.3.Threeorthogonalviewersdisplaytheslicedimagesindifferentdirections.The3Dviewontheleft-topshowsatri-planeimage,whichcanbemanipulatedasfollows;

Rotation:

Movethemousein3D-viewareawhilepressingtheleftbutton.Horizontalmovementsrotatetheimageobjectaroundafictitiousverticalaxis.Verticalmovementsrotateitaroundahorizontalaxis.Pressingtheshift-keydownwhilemovingthemousewillrotatetheimageobjectaroundtheaxisperpendiculartothemonitor.

ZoomIn/Out:

Movethemouseverticallyinthe3D-viewareawhilepressingtherightbutton.Movingthemousedownwardswillzoomin,movingupwardswillzoomout.

X/YTranslation:

Movethemousein3D-viewareawhileholdingitsright-keyandpressingtheshift-keydown.

Controlpanels

TheControl-panelviewisontheright,wherethefunctionalbuttonsare.Therearetwocontrolpanelsatthismoment,theimagecontrolpanelandtheROIcontrolpanel,whichcanbeselectedusingthetabsinthelowerrightcorner.

“Image”controlpanels

Bychoosingthe“Image”tab,youcangetapanelthatconsistsoffunctionsfor“OrthogonalImages”,“3Dvisualization”,“Opacity”,and“Animation”

“Orthogonalviews”

Thissectioncontrolsslicelocationsforimageviewingsection.

Thecrosslines,orslicemarker,superimposedoneachoforthogonalviewsindicatethepositionswheretheimageslicesinotherorthogonalviewsare.Slicemarkerscanbeenabledordisabledbyaselectorinthetopofimagecontrolpanel.

Youcanmovebetweenslicelocationsbytypingtheslicenumberorbyclickingthesmallarrowsnexttotheeditorbox.Youcanalsochangeslicelocationsbydouble-clickingtheimagingviewingareaatthelocationyouwanttoview.Theslicelocationsarealwaysdisplayedintheupperrightcorner.

Veryoften,multiple3Dvolumeimagesareopenedwithinoneprimaryimageviewwindow.Forexample,ifyouopenaDICOMdatasetthatislocatedinadirectorycontaining133DDWIs,then133Dvolumearenowloadedintothesameprimaryimageview