牙科放射线学1课件.ppt

1、整理ppt牙科放射線學牙科放射線學(1)(1)陳玉昆副教授陳玉昆副教授:高雄醫學大學高雄醫學大學 口腔病理科口腔病理科 07-31211012755 yukkwakmu.edu.twPanoramic Radiography(1)(2)環口放射線攝影術環口放射線攝影術 (1)(2)整理pptHistorical AspectTheory of Tomographic MovementConcept of Rotation Center&Focal TroughKinds of Image on PanorexRole of Dentist to Detect Carotid Atheroscl

2、erosis on PanorexNormal Structures on PanorexCommon&Position Errors on Panorex學 習 目 標整理ppt1.Eric Whaites:Essentials of dental radiography&radiology 3rd edition,Chapter 14-15,p.153-76.2.White&Pharoah:Oral radiology:principle&interpretation,5th edition,Chapter 10,p.191-209參考資料(1)3.Kaugars GE et al.Pan

3、oramic ghosts.Oral Surg Oral Med Oral Pathol 1987;63:103-84.Mason RA.Sydney Blackman 1898 1971 A pioneer of panoramic radiography.Dent Maxillofac Radiol 1998;27:371-55.Monsour PA.et al.Panoramic ghost images as an aid in the localization of soft tissue calcifications.Oral Surg Oral Med Oral Pathol 1

4、990;69:748-56 6.Brown RS et al.Synthetic hair braid extension artifacts in panoramic radiographs.JADA 1998;129:601-47.Aydin U.Tuberculous lymph node calcification detected on routine panoramic radiography:a case report.Dent Maxillofac Radiol 2003;32:252-4整理ppt8.Reuter I et al.Triple images on panora

5、mic radiographs Dent Maxillofac Radiol 1999;28:316-9 9.Kaohsiung Medical University Oral Pathology10.McDavid W et al.Real,double,and ghost images in rotational panoramic radiography.Dentomaxillofac Radiol 1983;12:122-811.Scheifele C.Hair artefacts in the head and neck region.Dentomaxillofac Radiol 2

6、003;32:255-7參考資料(2)12.Farman AF et al.The role of the dentist in detection of carotid atherosclerosis.S Afr Dent J 2001;56:549-5313.Eric Whaites:Essentials of dental radiography&radiology 4th edition,2007,p.198-9.14.Joo Csar Guimares Henriques et al.Panoramic radiography in the diagnosis of carotid

7、artery atheromas and the associated risk factors.The Open Dentistry Journal,2011,5,79-8315.Sansare K et al.Oral tuberculosis:unusual radiographic findings.Dentomaxillofac Radiol 2011;40:251-6 整理pptHistorical AspectSydney Blackman 1898-1971A pioneer of panoramic radiographyRef.4整理pptExamples of Panor

8、ex Obtained With The RotographMultiple unerupted teeth in an 8-yr old childDeveloping dentition in a 13-yr old childRef.4整理pptTheory of Tomographic Movement Types of Tomographic Movement1.Linear:Thin x-ray beam Broad x-ray beam2.Circular3.Ellipical4.Spiral5.Hypocycloidal整理pptLinear:thin x-ray beamDi

9、rection of movement of the filmDirection of movement of x-ray tubeheadPoints A-F all appear on different parts of the film and are blurred outPoint O,centre of rotation,appears in the same placeon the film throughout the exposure and is sharply definedLinear:broad x-ray beamX-ray tube-headFilmMultip

10、le center of rotationsZone within the focal plane(section of the patient):sharply defined on filmStartStartStartStartFinishFinishFinishFinishRef.1整理pptWidth of Focal Plane:Amount of movement (angle of swing)Large movementThin focal planeSmall movementThick focal planeRef.1整理ppt Film plane and direct

11、ion of film travelDirection of X-ray tube travelObject planeRotation centerBlurredSection in focusBlurredLinear Tomographic Principle Section in FocusRef.10整理pptHypocycloidalCircular/EllipticalSpiralDifferent Types of TomographyRef.1【數學】圓內旋輪線，內擺線 整理pptStartFinishTubehead orbitsbehind the headTubehea

12、d orbitsbehind the headCassette carrierorbits in front ofthe faceCassette carrierorbits in front ofthe faceFilm movesinside thecassette carrier Rotation CenterRefs.1,3X-ray sourceCassettecarrierBeamFilm insidecassettecarrier self orbit整理pptVarious Types of Rotation Center2 stationary3 stationaryCont

13、inuallymoving3 stationary&movingContinuous modeContinuous modeContinuous modeSplit modeRef.1整理pptX-raysourceShifting centerX-raysourceShifting centerShifting Rotation CentersFilmFilmRef.2整理pptShifting Rotation CentersRef.1Cassette carrierorbits around the front of the faceThe filmalso startsto moveS

14、tartShifting centersThe entire filmhas been exposedFinishShifting centers整理pptContinuous modeSplit modeThe entire filmhas been exposedFinishShifting centersCassette carrierorbits around the front of the faceThe filmalso startsto moveStartShifting centersRLRef.1Shifting Rotation Centers整理ppt3D focal

15、troughx=Height of x-ray beam(collimation)f =Height of filmd=Distance between focal trough&filmUpward angulationFinal image is slightlymagnifiedCollimation3D focal troughFocal TroughFilmRefs.1,2,3X-ray source Rotation center Film In focus的區域的區域(focal trough)整理pptIn front of focal troughBehindfocal tr

16、oughPatient is placedasymmetrically to the machineImpaction canbe seenImpactioncannotbe seen Vertical wall of focal trough in incisor regionClass IClass IIClass IIIShaded area outside focal trough is out of focus and will be blurredDifferent shapes of focal troughRefs.1,3Different Shapes of Focal Tr

17、ough整理pptX-ray sourcecassetteCassettecarrierOrbitOrbitbehindpatientOrbitbeforepatientCassettewith filminsideCassettecarrierRefs.10,catalogue of manufacturer Example of Panorex Machine整理pptControl panelX-raysource3D focal troughF-H planeAnteriorBite blockRefs.10,catalogue of manufacturer Example of P

18、anorex Machine整理pptKinds of Image Real (primary)imageDouble real(lateral)imageGhost(secondary)imageTriple image Real(Primary)image:When the object is located between the rotation center and the film(within the focal troughwith minimal unsharpness&distortion)ObjectX-raysourceRealimageRotationcenterFi

19、lmRef.10整理pptSplit movement patternContinuous movement patternReal image zoneReal image zoneMidline objectAlways blurred becausecorresponding to a region between rotation center¢ral plane of layerMay not be blurred sincecorresponding to a region include the sharply depictedplane in anterior regi

20、onDouble imageRef.10Real(Primary)Image整理pptDouble image of nasal gastric tubeRefs.9,10Double(Real)Lateral Image 整理pptGhostimageX-raysourceObjectRotationcenterFilm Ghost(Secondary)image:When the object is located between the rotation center&the x-ray source(outside the focal troughwith unsharpness an

21、ddistortion;the closer therotation center,the moredistortion of the image)Ref.10Ghost(Secondary)Image整理pptContinuous movement patternGhost envelopeCompositeSplit movement patternGhost envelopeCompositeOrthopantomograph-5Panelipse3 D ghost envelopePanorex3 D ghost envelopeSplit movement pattern3 D gh

22、ost envelopeRefs.3,5,10Ghost Envelope 整理pptHalf dry skullReal imageRGhost imageCurved x-ray filmGhostimageX-raysourceRotationcenterRefs.1,10Ghost Image(1)整理pptMidlinechainRefs.9,10Ghost Image(2)Cervical spineCervical spineBilateral double realCentral ghostBilateral double real+Central ghost=Triple i

23、mages整理pptFilmFilmRotation centerPosition 1Position 2X-raysourceGRGRGRX-raysourceR:In the real image zone moves in the same direction as the filmG:In the ghost image zone moves in the opposite direction as the filmImage is extremely blurredBlurring of Ghost ImageRef.10整理pptDistance from the x-ray so

24、urce(mm)x-ray sourceRotation centerCentral planeof the layerFilm0100200300400500102345GhostimageRealimageVerticalmagnificationHorizontalmagnificationHorizontalmagnificationVertical magnification=Horizontal magnificationMagnification factorMagnification of PanorexRefs.3,10整理pptSummaries of Ghost Imag

25、e1.The object is dense enough to block radiation2.It is located outside focal trough3.It is located inside ghost envelopeRef.31.It will always be distorted,especially the horizontal component.2.In most cases,it will be seen radiographically at a higher location than the primary object.3.It may not b

26、een seen on a clinical radiograph if superimposed over areas of dense anatomy.4.It may appear even if the primary object is not seen on the radiograph.5.It will always have some degree of radiopacity.Characteristics of a Ghost Image:6.Pronounced horizontal blurring indicates that the primary object

27、was at or close to center of rotation.7.It is reversed when compared with the primary image.8.It can be caused by physical objects such as earrings,a napkin chain,a necklace,a zipper on a pullover sweater,amalgam restorations or crowns,and radon or radium implants.9.It can be caused by anatomic stru

28、ctures,such as the body&ramus of the mandible or cervical vertebrae.10.It can be caused by parts of panoramic machine such as the chin rest or the letters R&L on the head positioner.11.It can be pathologic(e.g.a sialolith or an impacted third molar).整理pptRef.13CervicalvertebraeRamusPalateSummaries o

29、f Ghost Image整理pptRef.13Ramus(real image)Ramus(ghost image)RLSummaries of Ghost Image整理ppt Basic Principle:Location and appearance of ghost images shown on thepanoramic radiograph can provideinformation of the soft tissuecalcifications or predict thelocations of the soft tissuecalcificationsGhost Im

30、ages as an Aid to Localize Soft Tissue Calcifications整理pptLocation of lead sphere Ghost imageOcclusal viewLateral viewCentral ghostg Object is along the median planeRef.5No ghost imageNo ghost imageNo ghost image整理pptObject is buccal or lingual to mandibular body Ghost image appearanceOcclusal view

31、Location of lead sphereLateral viewRef.5No ghost imageNo ghost imageNo ghost image整理pptLocation of lead sphere Ghost imageOcclusal viewLateral view Object is inferior to ramusGhost imageRef.5No ghost imageNo ghost image整理ppt Location of lead sphere Ghost imageLateral viewOcclusal view Object is post

32、erior to condyleGhost imageGhost imageRef.5整理ppt Object is lateral or medial of ramus Ghost image Location of lead sphereOcclusal viewLateral viewGhost imageGhost imageGhost imageDouble primaryimageRef.5整理pptTriple ImageRef.8Retained foreign body(shrapnel)Ghost imageReal imagePosition of primary obj

33、ect did not change;creation of a triple image is due to slight differences in patient positioningTriple imageReal imageGhost image2 Ghost imagesReal image整理pptPositions of Object ShowingTriple ImagePosition 1Position 2Position 3Position 4Position 5Position 6Triple imageTriple imageTriple imagea:X-ra

34、y beamb(yellow arrows):direction of tube movementc:path of rotation centerd:center of image layerRef.8Triple image整理pptPositions of Objects Showing I,II&III ImagesRef.8Center of rotationLeftRightDiagram showing the areas where the test object is portrayed once(IA,IB),twice(II)and thrice(III).The sol

35、id white line indicates the path of rotation center&the dotted line the center of image layersI AI BII III III AIIIBIIIRRRLLLLRDiagram showing the location of the 1,2&3 images&the extent of distortion of the test object in relation to regions IA,B,II&III.The path of rotation center is shown as a sol

36、id white line.Note how triple images are generated in region III整理pptPositions of Object is Related to the Formationof Single,Double and Triple ImagesTriple image:One real&two ghostimages(diamond-shaped area immediatelydistal to path ofrotation of center)Two lateral real andone central ghostimages(c

37、ervical spine)abc1 x2 x3 xRef.8X-ray beam moves from its starting point to the anterior rotation center creates a single(1x)&an initial double(2x)imageMoves around the anterior center creates single(1x)&double images(2x)of objects in the central regionMoves from the anterior rotation center to the e

38、nd of tube movement completes the formation of lateral images(2x)&also portrays the central region for a third time(3x)整理ppt Role of Dentist to Detect Carotid AtherosclerosisAtheroma：Calcified plaques especially composed of lipids and fibrous tissue deposited on the walls of blood vessels trigger at

39、herosclerosis.Atherosclerosis：A chronic inflammatory disease of an immunological nature,characterized by thickening and loss of elasticity of the arterial walls,associated with the presence of atheromas.整理ppt Development of AtherosclerosisDevelopment of atherosclerosis:(A)Cross sectional cut of the

40、artery when it was still whole(B)Initial injury of the endothelium(C)The atheromatous plaque formed(D)A thrombus associated with the plaque,completely obstructing the hollow passage of the vessel Ref.14(A)(B)(C)(D)整理ppt Effect of Carotid Atherosclerosis*When affect the carotids(supply the brain)stro

41、kes*When affect the coronary(supply the heart)myocardial infarction*Result in the death of thousands of people all over the world Ref.14Blood clotFattydepositsInternalcarotidarteryCommoncarotidarteryCerebralarteriesBlood supply from the heart整理pptDiagrammatic Illustration of Panorexof Cartoid Athero

42、sclerosis(1)Ref.14AC1C1C2C2C3C3C4C4Why is PANOREX?1.Low radiation doses,low cost and has technical simplicity2.Normally deposited along the ascendant trajectory of the common carotid artery that bifurcates into internal and external carotid arteries comprised within the area of coverage of panoramic

43、 radiography整理pptCarotid atherosclerosisAtheroscleroticcalcifiesthat can be seen on panorexangle ofmandibleexternalcarotidarteryhyoidinternalcarotidarteryatheromacommoncarotidarterybifurcationRef.12Diagrammatic Illustration of Panorexof Cartoid Atherosclerosis(2)整理pptRef.14Some Examples(1)B整理pptRef.

44、14Some Examples(2)C整理pptSome Examples(3)Ref.12 Calcified carotid atheroma(arrow)Calcified atheromas of carotid artery bifurcation(arrows)整理pptMore Example(1)Ref.12 Bilateral carotid atherosclerosis Upper arrow on the right shows a calcified triticeous cartilage Calcified atheromatous plaque(arrow)整理

45、pptMore Example(2)Ref.7 A carotid plaque(arrows)visible in the left neck inferior&posterior to the angle of the mandible整理pptMore Example(3)Ref.7 Small carotid plaque(arrows)visible in the right&left neck,inferior&posterior to the angle of the mandible整理pptRefs.12,14Differentiate with Structures in

46、VicinityTriticeous(triticeal)cartilageHomogeneous RO when calcified-Regular oval shapes-2-4mm wide,7-9mm long-Superimposed on the airspace of pharynx-Close to superior portion of C4 Care needs to be taken to differentiate between calcified atheroma&other structures in vicinity that can also calcify(

47、thyroid cartilage,thyroid gland,triticeous cartilage,epiglottis)整理pptRefs.12,14Differentiate with Structures in VicinityThe best way to differentiate:PA radiograph taken by means of Modified Towne techniqueAtheromas dispose laterally to the vertebrae,whereas the triticeal cartilages(a more medial lo

48、calization)will not be observed(superimposed on the spinal column)整理pptPhleboliths in patientswith sclerosing hemangiomaThe calcifications are notcarotid calcifications&should be differentiatefrom carotid calcificationRef.12Differentiate with Venous Calcification整理pptRef.9More Example for Phlebolith

49、整理pptCalcified Lymph NodeShown on PanorexRef.7RLCarotid atheromaGhost imageCalcifiedlymph node整理pptOrgan Systems Frequently Affected in Extrapulmonary TuberculosisRef.7Site Lymph nodes(13-a85%)Pleura(9-77%)Genitourinary system(a2-74%)Central nervous system(1-b36%)Bones and joints(a2-17%)Gastrointest

50、inal system(a9-16%)Disseminated tuberculosis(7,12%)Pericardium(1-6%)Peritoneum(4%)aIn surgical specimensbIncluding spinal/vertebral tuberculosis整理pptExtrapulmonary Tuberculosis-Jaw Bones&TMJRef.15Resorption of condylar process整理pptExtrapulmonary Tuberculosis-Jaw Bones&TMJRef.15Resorption of angle of