1,CT 原理与算法,CT: computed tomography computerized tomography 计算机体层照相术 计算机断层照相术 计算机控制断层扫描术 computerized axial tomography (CAT) 计算机控制横轴向X线断层扫描术,2,X-CT,computed tomography tomo: Greek tomos section 希腊语 tomos 切面 graphy: Latin -graphia, from Greek, from graphein. writing or representation in a (specified) manner or by a (specified) means or of a (specified) object.,3,演示,4,CT,要点：,CT的地位、作用 CT发展的历史、现状、趋势 投影 CT数 反投影 重建算法概述,5,Hounsfield和Cormack因发明CT获得1979年诺贝尔医学和生理学奖。,Central Research Laboratories, EMI London,G. N. Hounsfield,A. M. Cormack,Tufts University Medford, MA, USA,Electric and Musical Industries 百代唱片公司,8,9,传统的X射线装置的缺点,影像重叠。深度方向上的信息至叠在 起，引起混淆。 密度分辨率低，对软组织分辨能力低。 所用剂量大。,10,11,12,13,14,CT,优点：,断层成像 密度分辨率高，对软组织分辨能力高。（相对于X射线成像术） 投影剂量小（相对于X射线成像术） 动态范围大（相对于X光片） 无损检测 存储方便,15,16,17,The Nobel Prize in Physiology or Medicine 1962,for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material.,London University,Harvard University,MRC Laboratory of Molecular Biology Cambridge,M. H. F. Wilkins,J. D. Watson,F. H. C. Crick,18,19,20,21,22,23,24,25,26,Portrait of a DNA Sequence by Roger Berry (1998) at the Life Sciences Addition building, University of California, Davis.,27,在法国名城Chambord有一座由达芬奇设计以及由法国的Franois一世于由16世纪(1519年)建造的建筑物中包含两个不相交的螺旋形组成的阶梯,28,Medcorp,IUPS,Enigma Publishing,29,CMA,NZMA,Medical Council,Aviation Med Ass,WHO,30,The Caduceus vs the Staff of Asclepius,31,Asclepius Wand,32,33,伏羲女娲交尾图的瓷瓶（清代）,34,35,石雕伏羲、女娲交尾图汉代 Stone statue, a depiction of sexual intercourse between Fuxi and Nuwa, Han Dynasty. Now in the collection of the Sichuan Museum.,36,山东嘉祥武氏祠东汉画像石中的伏羲、女娲及小人像,37,38,39,A. F. Cournand,W. Forssmann,D. W. Richards,The Nobel Prize in Physiology or Medicine 1956,for their discoveries concerning heart catheterization and pathological changes in the circulatory system,Columbia University,Columbia University,Mainz University Federal Republic of Germany,40,41,股动脉,Cardiac catheterization,42,导管,43,44,荣获1946年诺贝尔生理学或医学奖 发现X线照射引起基因突变,缪勒 Hermann Joseph Muller 美国 印地安那大学 1890年-1967年,45,Johann Radon entered the University of Vienna where he was awarded a doctorate in 1910 for a dissertation on the calculus of variations. The year 1911 he spent in Gttingen, became assistant professor at the University of Brnn (now Brno) for a year and then moved to the Technische Hochschule in Vienna. In 1919 Radon became assistant professor at Hamburg becoming a full professor in Greifswald in 1922. He was appointed to the University of Vienna in 1947 and he remained there for the rest of his life.,Johann Radon Born: 16 Dec 1887 in Tetschen, Bohemia (now Decin, Czech Republic)Died: 25 May 1956 in Vienna, Austria He worked on the Calculus of variations, Differential geometry and Measure theory.,46,47,