医学影像学：放射学(医学影像)课件

1、RADIOLOGY(Medical Imaging)RADIOLOGY(Medical Imaging)Overview and Principles of Diagnostic ImagingOverview and Principles of DiaMedical ImagingDiagnostic ImagingInterventional RadiologyDiagnostic RadiologyUltrasonographyNuclear ImagingDiagnosisTherapyMagnetic Resonance Medical ImagingDiagnostic Imag

2、The aim of our course is mainly to study the basic knowledge about diagnostic radiology: how to use x-rays, what can x-rays do for diagnosis of diseases, the various examination modalities, and what are the advantages and limitations of these examination modalities. Although a brief introduction of

3、magnetic resonance (MR) is included in our course , ultrasound (US) and nuclear imaging will be taught in additional courses. The aim of our courDiagnostic Imaging MethodsDiagnostic imaging is a dynamic specialty that has undergone rapid change with continuing advancements in technology.Not only has

4、 the number of imaging methods increased but each one continues to undergo improvement and refinement of its use in medical diagnosis.Diagnostic Imaging MethodsDiagRadiographic TechniquesThe principle of selectionSafeAccurateConvenientEconomicRadiographic TechniquesThe priPrinciples of x-rayThe x-ra

5、y beam is produced by bombarding a tungsten target with an electron beam within an x-ray tube.Principles of x-rayThe x-ray b As x-ray pass through the human body they are attenuated by interaction with body tissues(absorption and scatter), resulting in an image pattern recognizable as human anatomy.

6、 As x-ray pass through医学影像学：放射学(医学影像)课件natural contrastnatural contrast artificial contrast artificial contrastRadiographic Techniques X-ray filmFluoroscopySoft beam radiography for breastContrast administration examinationRadiographic Techniques X-ray Radiographic TechniquesContrast administration

7、examinationcontrast mediumHigher density contrast：barium，iodineLower density contrast ：gas agentsThe way of contrast administrationdirect：take orally、enema、inject into the vesselsindirect：inject into the veins，physiological excretionRadiographic TechniquesContras医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件Dig

8、ital Radiography DRComputed Radiography CR，(imaging plate IP)Digital Fluorography， DF (影像增强电视系统，IITV)Digital Radiography, DR (flat panel detectors)Digital Radiography DRComputPrinciple of CRPrinciple of CRPrinciple of DRPrinciple of DRPACS Picture Archiving and Communicating SystemRIS Radiological I

9、nformation System RISPACSWebPACS Picture Archiving and ComPACS 示意图PACS 示意图Digital Subtraction Angiography (DSA)Digital Subtraction AngiograpPrinciple of DSA ImagingA method for showing contrast-filled vessels without any interfering background.“Mask” image, just before the contrast medium is injecte

10、d, onto which the images with contrast medium were overlaid to coincide, producing a subtraction image only displaying the contrast-filled vessels.Principle of DSA ImagingA mangiographyangiographyComputed TomographyComputed TomographyIntroduction Since its introduction in the 1970s, CT has been show

11、n to have wide applications within all the radiological subspecialities. It has become a primary imaging technique in the clinic.Introduction Since its iWhat is CTCT images a section or slice of the patientTwo-dimensional image of the sliceReconstructed image(array of quantized gray scale values or

12、pixels)Pixel values(CT number)are related to the linear attenuation of the corresponding volume element of the slice (voxel)What is CTCT images a secBasic Components of a CT GantryTableGeneratorConsoleComputerFrom the outside.TableGantryGeneratorBasic Components of a CT GantrInside a scannerTubeDete

13、ctorDASTube collimatorInside a scannerTubeDetectorDAHow does a CT work Image ProcessingData detection & acquisitionX-ray sourceHow does a CT work Image Proce医学影像学：放射学(医学影像)课件CT valueCT value图像质量的进展.二 维 横 断 面 到 三 维 图 像 重 建图像质量的进展.二 维 横 断 面 到 三 维 图 像 Equipment Conventional CT Spiral (helical) CT Multi

14、slice CT (MSCT) Electron beam CT (EBCT) Dual source CT (DSCT) Equipment医学影像学：放射学(医学影像)课件Multislice CT（MSCT） Multislice CT, also known as multidetector CT(MDCT) or multidetector row, is the latest breakthrough in CT technology. It has trans-formed CT from a transaxial cross-sectional technique into a

15、 true three-dimensional imaging modality. Major attributes that are improved are the z-axis coverage speed and the longitudinal resolution (isotropic arrays). Multislice CT（MSCT） Mult医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件Multi-Slice vs. Single Slice TechnologyKey benefits of multi-slice

16、 CT over single slice scannersincreased coverage in a single breathholdbetter image quality decreased acquisition time thinner slices improved 3D post processing techniquesMulti-Slice vs. Single Slice TClinical Benefits of Multislice CTShorter Scan Time0.37sLarger VolumeClinicalApplicationIsotropic

17、Resolution0.4mmClinical Benefits of Multislic多层CT发展迅猛 1992： 2层 1998： 4层 2001：16层 2003：64层 2005：双源 2006:256层 2007:320层多层CT发展迅猛 1992： 2层单源CT双源CT单源CT双源CTSOMATOM Definition世界首台双源CT任意心率条件下的时间分辨率83 ms= 83 msRotation Time4Temporal Resolution =SOMATOM Definition世界首台双源CT任意医学影像学：放射学(医学影像)课件CT Techniquesplain

18、scanningcontrast enhancementother contrast examinationHRCT (high resolution computed tomography)CT Techniquesplain scanning医学影像学：放射学(医学影像)课件HRCTHRCTCT TechniquesReconstruction Surface Shaded Display (SSD）Maximum Intensity Projection ( MIP）Volume Rendering (VR）Multiplanar Reconstruction (MPR）Curved M

19、ultiplanar Reconstruction (CMPR）Virtual Endoscopy (VE）CT TechniquesReconstruction 齿状突骨折伴环枕、环枢关节脱位Fracture of the odontoid process with dislocation of the atlanto-occipital and atlanto-axial joints齿状突骨折伴环枕、环枢关节脱位Fracture of theHeadlinestenosisCourtesy of University of Erlangen, Department of Radiolog

20、y and Institute of Medical Physics SOMATOM Sensation 646 sec for 350 mm64 x 0.6mm (2x32)Resolution 0.4 mmRotation 0.37 sec120 kV / 150 mAs缺乏造影剂？扫描比造影剂跑得快！HeadlinestenosisCourtesy of Un医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件Aneurysm and DissectionAneurysm and Dissection CTA of living donor transplantation

21、 CTA of living donor transplan CT TechniquesFunction and other techniques Perfusion Quantitative CT (QCT)CT coronary artery angiography Function CT TechniquesFunction and ot 常 规 CT Time to Peak CBF 随 访 颅 内 动 脉 栓 塞 随 访 CT 显 示 液 化 灶embolism of intracranial arteries, follow-up CT image shows the infarc

22、tionmale, 56, 150min after the onset 常 规 CT T左前降支狭窄Left anterior descending branch stenosis左前降支狭窄Left anterior descendingCT coronary artery VECT coronary artery VESpeed 4D - Cardiac Imaging with 0.37 s RotationImproved Diagnostic Confidence for Plaque AnalysisCourtesy of Thorax Center Rotterdam, the

23、 NetherlandsSpeed 4D - Cardiac Imaging wit扫描层厚、空间分辨率和冠脉成像扫描层厚、空间分辨率和冠脉成像SOMATOM Sensation CardiacCardiac MorphologyAdditional Clinical Information received from ECG-gated scan Calcified ThrombusAortic ValveECG-Gated ScanSOMATOM Sensation CardiacAddit16-Slice Cardiac Function Analysis syngo Argus, CT

24、 4D and LV-FunctionCourtesy of Grosshadern Clinic EF EDV ESV Mass Wall Thickening MovieCompatible to MRI and CT Data16-Slice Cardiac Function AnalHeadlineSpeed 4D - Cardiac Imaging with 0.37 s RotationImproved Diagnostic Confidence for Plaque Analysis6 months follow up of stent patency,no in-stent r

25、e-stenosis, 67 bpm16x0.75 mm, 185 ms,12 cm in 16 s,only 80 ml contrastCourtesy of Thorax Center Rotterdam, the NetherlandsHeadlineSpeed 4D - Cardiac ImaAdvantage and Disadvantage of CTAdvantage：Tomographical imageHigh density resolutionContrast enhancement have wide applicationsDisadvantage：Expensiv

26、eX-ray Advantage and Disadvantage of Magnetic Resonance Imaging (MRI） Imaging method using a strong magnetic field and gradient field to localize burst of radiofrequency signals coming from a system of spins consisting of reorienting hydrogen (H) nuclei(protons) after they have been disturbed by rad

27、iofrequency pulses.Magnetic Resonance Imaging (MRecent progress in the art of MRI Magnetic resonance imaging (MRI) is a noninvasive method of mapping the internal structure of the body which completely avoids the use of ionizing radiation and appears to be without hazard. MRI has now rapidly progres

28、sed from being a technique with great potential to one which has become the primary, and often the only ,diagnostic method required for many clinical problems. Recent progress in the art of Recent progress in the art of MRI The phenomenon of MR was described independently but almost simultaneously b

29、y Bloch and Purcell in 1946 and for their discovery they were jointly awarded the Nobel Prize for Physics in 1952. Because the use of MR for imaging required a method for spatial localization, Lauterbur and Mansfield were jointly awarded the Nobel Prize for medicine in 2003.Recent progress in the ar

30、t of MR has the ability to display structures in a transverse or axial fashion, similarly to CT. However, MR has the additional advantage of being able to produce images in virtually any orientation. The common display orientations used are sagittal and coronal as well as axial planes. MR has the ab

31、ility to In general, during an MR examination three forms of MR image can be produced: T1 weighted image (T1WI), T2 weighted image (T2WI), and proton density weighted image (PDWI). Tissues or substances with short T1 relaxation times (short T1) have high signal intensity and appear bright on T1WI, w

32、hereas tissues or substances with long T1 relaxation times (long T1) have low signal intensity and appear black on T1WI. In general, during an Tissues or substances with short T2 relaxation times (short T2) have low signal intensity and appear black on T2WI, whereas tissues or substances with long T

33、2 relaxation times (long T2) have high signal intensity and appear bright on T2WI. Tissues or substances w医学影像学：放射学(医学影像)课件 Water appears black on T1WI and bright on T2WI because it has long T1 and long T2 relaxation times. Fat appears bright on T1WI and medium signal intensity on T2WI because it ha

34、s short T1 relaxation times and medium T2 relaxation times. Muscle appears medium signal intensity on both T1WI and T2WI because it has medium T1 and medium T2 relaxation times. Cortical bones, calcium, and lung tissues appear low signal intensity (black) on PDWI as well as T1WI and T2WI because the

35、y have very litter hydrogen (proton). Water appears black onImaging pulse sequence spin echo (SE) sequence inversion recovery (IR) sequence a variety of acronymic gradient echo (GR or GRE) sequence techniques (e.g. STIR, FISP, and FLASH, etc.) The fastest sequence of MRI used today is echo planar im

36、aging (EPI) Imaging pulse sequence spin ecMRI characteristicsmultiple sequencesprovide images in any anatomic planeflowing effectscontrast enhancementMRI characteristicsmultiple se医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件膝关节外伤，胫骨骨折膝关节外伤，胫骨骨折Application of MRI Enhancementtu

37、morblood-brain barriermore sensitiveMRAApplication of MRI EnhancementMRI contrast mediumGd-DTPA paramagnetic contrast mediumAMI-25 superparamagnetic contrast mediumMRI contrast medium医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件MRI EquipmentMRI Equipment Low field MR， open system MR Low fielRe

38、cent progress in MRI unitPolarization of magnetic fieldSpecial MR UnitFaster and stronger magnetic resonance gradientsRF coil Recent progress in MRI unitPolRF CoilsRF CoilsAdvanced Imaging TechniquesWhole body MR screening It is an ideal modality for the purposes of healthcare screening that has bot

39、h high sensitivity and specificity with out radiation hazard. The true benefit of whole body MR imaging is in the variety of disease found. Its value is in its reliability and accuracyAdvanced Imaging TechniquesWhoPatient with PlasmocytomaTSE T1+2w, PAT 2Schlemmer, Claussen et al.University Tuebinge

40、n (Germany)Patient with PlasmocytomaTSE SH Changhai Hospital全身成像多发转移SH Changhai Hospital全身成像3D ToFTR/ TE 35 /3.6 ms, 192x512,SL 0.8 mm,108 partitionsTA: 6:44 minHigh-Resolution ToF at 3T3D ToFHigh-Resolution ToF at 3ToF MRA of the HandHigh-resolution 3D ToF with water excitationNo contrast agent3D F

41、LASH fat satSL 1 mm, 256x512, 215 partitionsTR/TE 33/4.9 ms, TA: 9:00 min ToF MRA of the HandHigh-resolu高分辨乳腺成像SH Changhai Hospital高分辨乳腺成像SH Changhai Hospital乳腺动态扫描SH Changhai Hospital乳腺动态扫描SH Changhai Hospital2D PACE 自由呼吸腹部成像T2W TSE Matrix 3842D PACE T2W TSE Matrix 3842D PACE with fatsat 北京阜外医院2D P

42、ACE 自由呼吸腹部成像T2W TSE MatrixOther MRI TechniquesFat suppressionMRC （Cinema）MRAMRCP, MRUFunctional MRI（fMRI）MRSDWIPWIOther MRI TechniquesFat suppSubsecond 3D MRA of Aortic AneurysmSubsecond 3D MRA of Aortic Ane High Resolution MR Angiographyhigh resolution 512 matrix in 18 sec aquisition time High Reso

43、lutionSubsecond 3D MRA of Aortic Arch StenosisSubsecond 3D MRA of Aortic ArcSubsecond MRA of Aortic DissectionSubsecond MRA of Aortic Dissec3D TrueFISP Coronary MRA Flexibility:the choice is yoursbreathhold in 20 sec3D TrueFISP Coronary MRA FlexiDark Blood Coronary MRA with 3D TSE & NavigatorsDark B

44、lood Coronary MRA with 3Schlemmer, Claussen, Univ. Hospital Tuebingen, GermanyMRCP post cholecystectomyin 1.8 secondsMultiple liver cystsSchlemmer, Claussen, Univ. Hos医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件医学影像学：放射学(医学影像)课件Ureter cancerMRU BH TA:4secs Fl2d t1w fs with contrast VIBE SL 2mm TA :18 secs wit

45、h contrast 河北省肿瘤医院Ureter cancerMRU BH TA3D TSE IACSL 0.5mmMIP北京阜外医院3D TSE IAC北京阜外医院哈尔滨医科大学第一附属医院哈尔滨医科大学第一附属医院Increased BOLD Effects at 3.0T BOLD contrast is in the range of 3.0T = 5 to 10%1.5T = 1 to 2%3.0T1.5TIncreased BOLD EffectsIncreased BOLD Effects at 3.0TRRRWhite matter tractRRRWhite matter t

46、ract医学影像学：放射学(医学影像)课件acd手动功能区肿瘤天津环湖医院acd手动功能区肿瘤天津环湖医院DWI/PWI-based “Risk Maps”T2ADCMTTCBFCBVHWIInitial Low b+ADC01Courtesy O. Wu, G. Sorensen, MGHFollow-up T2(2 Months)CombinedDWI+HWIDWI/PWI-based “Risk Maps”T2ADCCourtesy of Dr. R. White, Cleveland Clinic, Cleveland, USASiemens was the first to offe

47、r these as a productInfarct Evaluation: Cine & Late EnhancementCourtesy of Dr. R. White, ClevClinical Protocols for Infarct EvaluationCourtesy of Northwestern University Chicago, USA TrueFISP cine Late Enhancement Clinical Protocols for InfarctGadolinium Contrast Enhancement in Myocardial InfarctionEx-vivo comparison of TTC and Gd-enhanced MRI in infarcted myocardiumCourtesy of Dr. R. Judd, Northweste