1、Medical ImagingDiagnostic ImageologyInterventional RadiologyDiagnostic RadiologyUltrasonographyNuclear ImagingDiagnosisTherapyScintigraphy學(xué)習(xí)醫(yī)學(xué)影像學(xué)的注意點了解不同成像技術(shù)的基本原理及其圖像特點掌握圖像的觀察與分析方法，了解正常影像學(xué)表現(xiàn)和常見病的異常表現(xiàn)及其病理基礎(chǔ)掌握不同成像手段在不同疾病診斷中的作用與限度影像學(xué)檢查價值很大，但有限度，需結(jié)合臨床資料Diagnostic Imaging MethodsDiagnostic imaging is a d

2、ynamic specialty that has undergone rapid change with continuing advancements in technology.Not only has the number of imaging methods increased but each one continues to undergo improvement and refinement of its use in medical diagnosis.第一章 X線成像Radiography第一節(jié) 普通X線成像一 、 X線成像基本原理與設(shè)備 X線的產(chǎn)生，X線是真空管內(nèi)高速行進

3、的電子流轟擊鎢靶時產(chǎn)生的The x-ray beam is produced by bombarding a tungsten target with an electron beam within an x-ray tube.X線的特性穿透性：與管電壓和物體的密度與厚度相關(guān)熒光效應(yīng)：透視的基礎(chǔ)感光效應(yīng)：攝影的基礎(chǔ)電離效應(yīng)：放射治療的基礎(chǔ)、X線防護X線成像基本原理As x-ray pass through the human body they are attenuated by interaction with body tissues(absorption and scatter), re

4、sulting in an image pattern recognizable as human anatomy.基本條件X線具有穿透性存在密度(density)與厚度(thick or thin)的差異顯像過程二、 X線圖像特點X線圖像不同灰度的影像反映了人體解剖結(jié)構(gòu)和病理狀態(tài)的不同密度和厚度X線圖像是重疊的，有一定程度的放大，并可產(chǎn)生偽影三、 X線檢查技術(shù)Radiographic Techniques自然對比(natural contrast) 人工對比(artificial contrast)三、 X線檢查技術(shù)Radiographic Techniques 普通檢查透視(Fluoros

5、copy)、攝片(Plain film)特殊檢查體層攝影(conventional tomography)、軟線攝影(soft beam radiography)造影檢查 contrast administration examination三、 X線檢查技術(shù)Radiographic Techniques造影檢查對比劑(contrast medium)高密度對比劑：鋇劑(barium)、碘劑(iodine)等低密度對比劑：氣體(gas agents)造影方式直接引入：口服、灌注、穿刺注入間接引入：經(jīng)靜脈注入對比劑，生理性排泄檢查前準(zhǔn)備及造影反應(yīng)的處理三、 X線檢查技術(shù)Radiographic

6、TechniquesX線檢查方法的選擇原則(principle)安全(safe)、準(zhǔn)確(accurate)、簡便(convenient)、經(jīng)濟(economic)四、X線診斷的臨床應(yīng)用成像清晰、經(jīng)濟、簡便胸部、骨骼、胃腸道首選五、X線檢查中的防護技術(shù)方面：屏蔽防護、距離防護患者方面：照射次數(shù)、范圍、條件，遮蓋工作人員方面：自我防護，定期體檢第二節(jié) 數(shù)字化X線成像數(shù)字化X線成像（digital radiology） 1. CR（影像板，imaging plate IP) 2. DF (影像增強電視系統(tǒng)，IITV) 3. DR（平板探測器，flat panel detectors)Principl

7、e of CRPrinciple of DR感光度與解析度不能很好兼顧可以同時做到高感光度和高解析度第二節(jié) 數(shù)字化X線成像DR的臨床應(yīng)用 圖像軟件：Inverse Topography (組織平衡軟件)Soft tissue + Bone detail at the same time動態(tài)范圍寬一次曝光可通過窗寬,窗位的調(diào)整獲得從軟組織到骨骼不同的影像,甚至可以清楚到頭發(fā)。 第三節(jié) 數(shù)字減影血管造影(Digital Subtraction Angiography, DSA)DSA成像基本原理血管造影時，由于血管與骨骼和軟組織影像重疊，致使血管顯影不請。將X線圖像數(shù)字化，用1幀血管內(nèi)不含對比劑的

8、圖像作為蒙片，和1幀含對比劑的圖像相減，使圖片中代表骨骼和軟組織的數(shù)字相抵消，只剩有對比劑的血管顯影清晰。有助于診斷和做各種介入手術(shù)Principle of DSA ImagingA method for showing contrast-filled vessels without any interfering background.“Mask” image, just before the contrast medium is injected, onto which the images with contrast medium were overlaid to coincide, p

9、roducing a subtraction image only displaying the contrast-filled vessels.DSA檢查技術(shù)和臨床應(yīng)用DSA techniques and clinical applications動脈(percutaneous arterial)DSA靜脈(percutaneous venous)DSA旋轉(zhuǎn)(rotate)DSA，3D立體實時成像第二章 計算機體層成像(Computed Tomography)Introduction Since its introduction in the 1970s, CT has been shown

10、 to have wide applications within all the radiological subspecialities. It has become a primary imaging technique in the clinic.第一節(jié) CT成像基本原理與設(shè)備基本原理 用X線束對人體檢查部位一定厚度的層面進行掃描，由探測器接受衰減的X線，并由光電轉(zhuǎn)換器變?yōu)殡娦盘?，再由模?shù)轉(zhuǎn)換器變?yōu)閿?shù)字進行計算機處理，獲得該層面的每個體素的X線衰減系數(shù)，再由數(shù)模轉(zhuǎn)換器把每個體素的數(shù)字轉(zhuǎn)換成不等灰階度的像數(shù)，按矩陣排列，構(gòu)成CT圖像What is CTCT images a sectio

11、n or slice of the patientTwo-dimensional image of the sliceReconstructed image(array of quantized gray scale values or pixels)Pixel values(CT number)are related to the linear attenuation of the corresponding volume element of the slice(voxel)CT設(shè)備( Equipment)普通CT Conventional CT螺旋CT Spiral (helical)

12、CT多層螺旋CT Multislice CT (MSCT）雙源多層螺旋CT Dual Source CT (DSCT）電子束CT Electron beam CT (EBCT)平板CT Flat panel CT世界第一臺雙源 CTSOMATOM Definition 球管球管探測器探測器多層螺旋CT的趨勢“多排和多層”1998年，8排或16排或32排探測器，實現(xiàn)4層掃描，2002年，24排探測器，實現(xiàn)16層掃描；2004年，32或64排探測器，實現(xiàn)64層掃描；2005年，128層掃描，雙球管2006年，256層掃描，2007年，320層掃描200？年，平板探測器，1024X768掃描CT球管

13、的趨勢：0.75MHU1.0MHU1.5MHU2.0MHU3.0MHU-3.5MHU4.0MHU5.3MHU6.3MHU7.5MHU.2003年SIEMENS 0MHU球管 Clinical Benefits of Multislice CTShorter Scan Time0.33sLarger VolumeClinicalApplicationIsotropic Resolution0.4mmmore detailedmore speedymore volume第二節(jié) CT圖像特點數(shù)字圖像(digital imaging)矩陣(matrix)像素與體素(pixel and voxel)CT

14、值(CT pixel numbers)窗寬、窗位(window width and centre)CT value圖像質(zhì)量的進展.二 維 橫 斷 面 到 三 維 圖 像 重 建第三節(jié) CT檢查技術(shù)CT Techniques平掃(plain scanning)對比增強掃描(contrast enhancement)造影掃描(other contrast methods)HRCT (high resolution computed tomography)第三節(jié) CT檢查技術(shù)CT Techniques重建技術(shù)(Reconstruction Techniques)表面遮蓋法重建（Surface Sha

15、ded Display, SSD）最大密度投影（Maximum Intensity Projection, MIP）容積再現(xiàn)（Volume Rendering, VR）多層面重建（Multiplanar Reconstruction, MPR）曲面多層重建（Curved Multiplanar Reconstruction, CMPR）仿真內(nèi)窺鏡技術(shù)（Virtual Endoscopy, VE）HeadlinestenosisCourtesy of University of Erlangen, Department of Radiology and Institute of Medical

16、Physics SOMATOM Sensation 646 sec for 350 mm64 x 0.6mm (2x32)Resolution 0.4 mmRotation 0.37 sec120 kV / 150 mAs缺乏造影劑？掃描比造影劑跑得快！HeadlineEmotion 16 6.5 for 235.5mm16 x 1.2 mmPich 1.3Rotation 0.6 sec130 kV90 effective mAsCourtesy of Jiangsu Prov People Hospital / NanJin, ChinaHeadlineCourtesy of Jiangs

17、u Prov People Hospital / NanJin, ChinaEmotion 16 6.5 for 235.5mm16 x 1.2 mmPich 1.3Rotation 0.6 sec130 kV90 effective mAsHeadlineCourtesy of Jiangsu Prov People Hospital / NanJin, ChinaEmotion 16 10s for 258mm16 x 1.2 mmPich 1.2Rotation 1.0 sec130 kV90 effective mAsHeadlineCourtesy of Jiangsu Prov P

18、eople Hospital / NanJin, ChinaEmotion 16 10s for 258mm16 x 1.2 mmPich 1.2Rotation 1.0 sec130 kV90 effective mAs肺動靜脈瘺（兩側(cè)）曲面重建Arteriovenous fistula of pulmonary vessels(bilateral)Aneurysm and Dissection第三節(jié) CT檢查技術(shù)CT Techniques功能(function)及其他檢查灌注成像 Perfusion 骨密度測定 Quantitative CT (QCT)冠狀動脈造影 CT coronary

19、 artery angiography 骨密度分析區(qū)（五點修飾輪廓）模板的水樣部分模板的骨樣部分 男 性, 56 歲, 癥 狀 后150 min 常 規(guī) CT Time to Peak CBF 隨 訪 顱 內(nèi) 動 脈 栓 塞 隨 訪 CT 顯 示 液 化 灶embolism of intracranial arteries, follow-up CT image shows the infarctionmale, 56, 150min after the onset左冠狀動脈鈣化狹窄CT coronary artery VE掃描層厚、空間分辨率和冠脈成像SOMATOM Sensation Ca

20、rdiacCardiac MorphologyAdditional Clinical Information received from ECG-gated scan Calcified ThrombusAortic ValveECG-Gated Scan16-Slice Cardiac Function Analysis syngo Argus, CT 4D and LV-FunctionCourtesy of Grosshadern Clinic EF EDV ESV Mass Wall Thickening MovieCompatible to MRI and CT DataMCBLCA

21、小分支的動脈瘤第四節(jié) CT診斷的臨床應(yīng)用優(yōu)點：斷層圖像密度分辨率高可反映造影劑在不同時相的變化，大大擴展了臨床檢查范圍缺點：較昂貴X線損傷第四節(jié) CT診斷的臨床應(yīng)用中樞神經(jīng)系統(tǒng)頭頸部胸部心臟與血管腹部盆腔骨骼系統(tǒng)第三章 超聲成像(ultrasonography,USG)第四章 磁共振成像（Magnetic Resonance Imaging , MRI） Imaging method using a strong magnetic field and gradient field to localize burst of radiofrequency signals coming from a

22、 system of spins consisting of reorienting hydrogen (H) nuclei(protons) after they have been disturbed by radiofrequency pulses.磁共振成像是利用體內(nèi)氫原子核在強磁場內(nèi)發(fā)生磁矩，用射頻發(fā)生共振提供能量，改變磁矩；停止射頻，恢復(fù)磁矩，釋放能量，產(chǎn)生信號，經(jīng)計算機處理，形成MR圖像。 成 像 基 本 原 理縱向磁化（longitudinal magnetization）縱向磁化減小與橫向（transverse）磁化馳豫與弛豫時間（relaxation time）馳豫時間與M

23、RI成像脈沖序列（pulse sequence）與加權(quán)像（weighted imaging， WI）T1加權(quán)像（T1WI）： 短TE, 短TRT2加權(quán)像（T2WI）： 長TE, 長TR MRI 設(shè) 備（MRI Equipment） Low field MR， open system MRRecent progress in MRI unitPolarization of magnetic fieldSpecial MR UnitFaster and stronger magnetic resonance gradientsRF coil RF CoilsAdvanced Imaging Tec

24、hniquesWhole body MR screening It is an ideal modality for the purposes of healthcare screening that has both 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 accuracyPatient

25、with PlasmocytomaTSE T1+2w, PAT 2Schlemmer, Claussen et al.University Tuebingen (Germany)Neuro-Ocular Plane ImagingImage courtesy of Dr Scarabino, Casa Sollievo della Sofferenza, Italy.3T Imaging Resembles SpecimenMRI 圖 像 特 點MRI characteristics多參數(shù)成像（multiple sequences）多方位成像流動效應(yīng)對比增強MRI 圖 像 特 點MRI cha

26、racteristics多參數(shù)成像多方位成像（provide images in any anatomic plane）?，F(xiàn)在有挑戰(zhàn)。流動效應(yīng)對比增強MRI 圖 像 特 點MRI characteristics多參數(shù)成像多方位成像流動效應(yīng)（flowing effects）對比增強3D ToFTR/ TE 35 /3.6 ms, 192x512,SL 0.8 mm,108 partitionsTA: 6:44 minHigh-Resolution ToF at 3TMRI 圖 像 特 點MRI characteristics多參數(shù)成像多方位成像流動效應(yīng)對比增強(contrast enhancem

27、ent)MRI增強掃描的適應(yīng)癥 application of MRI enhancement腫瘤的鑒別與定性(tumor)血腦屏障是否破壞(blood-brain barrier)提高病變的發(fā)現(xiàn)率(more sensitive)MRI造影劑(contrast medium)主要分為兩類：順磁性物質(zhì)(Gd-DTPA) paramagnetic contrast medium超順磁性物質(zhì)(AMI-25,菲力磁) superparamagnetic contrast medium轉(zhuǎn)移瘤T1C+，T2肝Ca(CT,T1,T2FS,T1C+) MRI檢查技術(shù) MRI Techniques脈沖序列（pul

28、se sequence）SE序列，梯度回波（gradient echo）序列，回波平面成像（echo-planar image，EPI）脂肪抑制（fat suppression）MRC （Cinema）MRI對比增強（contrast enhancement）MRA(MR血管造影)MRI水成像(MRCP, MRU, MRM)功能性MRI成像（fMRI）MRSDWIMRI檢查應(yīng)注意的問題禁忌證（contraindication）： 起搏器（pacemaker） 動脈瘤金屬夾（aneurysm clips） 眼球金屬異物（intraocular metallic foreign bodies） 危

29、重患者（serious patient）相對禁忌證：人工關(guān)節(jié)、體內(nèi)金屬異物、高熱患者、早期妊娠等檢查前注意事項Advantage and Disadvantage of MRIAdvantage：Multiple tomographical imageMore information from imagingHigh soft tissue resolutionContrast enhancement have wide applicationsDisadvantage：ExpensiveComplicationMore contraindication第四節(jié) MRI診斷的臨床應(yīng)用中樞神經(jīng)系統(tǒng)

30、頭頸部循環(huán)系統(tǒng)肌骨系統(tǒng)盆腔胸部腹部分子影像學(xué)Molecular imagingThough evolving continuously, the field of molecular imaging is expected to bring radiology into the forefront of disease diagnosis and therapy design through advances in three modalities: radionuclide, MR, and optical imaging. Molecular imagingPET/SPECTCT perfu