case study computed tomography (ct)
DESCRIPTION
Case Study Computed Tomography (CT). Non-invasive medical imaging techniques. 最传统的方法. Standard X-ray Lost spatial information Very limited use. X-ray. Use very high frequency sound (MHz) Safe Image in real time Equipment is not expensive. Limitation - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/1.jpg)
Case Study Computed Tomography (CT)
Non-invasive medical imaging techniques
![Page 2: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/2.jpg)
最传统的方法
Standard X-rayLost spatial
informationVery limited use
![Page 3: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/3.jpg)
X-ray
![Page 4: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/4.jpg)
Ultrasound (B超 )
Use very high frequency sound (MHz)Safe Image in real timeEquipment is not
expensive
LimitationStrong sound
absorption by bonesHard in brain studies,
or anywhere with bones
基本原理(物理的):波的折射与反射
![Page 5: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/5.jpg)
Computed Tomography A parallel sheet of X-ray Mathematical tools needed for successful
computed tomography (CT) imaging Basic principle is discovered more once 1979 Nobel Prize in Physiology and Medicine
was awarded to G. Hounsfield & A.M. Cormack jointly for realizing and bringing to medical use
![Page 6: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/6.jpg)
Computed Tomography
Not expensive to use Some drawbacks
Possible tissue damage from ionization
Low contrasts between different type of soft tissues
![Page 7: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/7.jpg)
Computed Tomography
There are many applications other than medical tomography:Astronomy---binary stars, coronal studyOceangraphy---acoustic probing of ocean
conditionsGeophysics---mantle flow, atmospheric studiesPorous Media---
![Page 8: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/8.jpg)
Hubble Image
![Page 9: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/9.jpg)
Hubble Image
![Page 10: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/10.jpg)
Hubble Image
![Page 11: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/11.jpg)
Hubble Image
![Page 12: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/12.jpg)
Test Object
![Page 13: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/13.jpg)
Model problem
![Page 14: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/14.jpg)
Model problem Coordinate axes satisfy
![Page 15: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/15.jpg)
Radon Transformation
Assume the density function of the test object is given by
The scan data can be written as
Question: how to recover from
![Page 16: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/16.jpg)
Least Square Method To understand the idea
behind, consider3*3 small objectHomogenous blocksThe block densities
either 0 or 1 How to achieve the
reconstruction?
![Page 17: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/17.jpg)
Least Square Method Density 1:
Density 0:
![Page 18: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/18.jpg)
![Page 19: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/19.jpg)
Scan Only 2 Directions
![Page 20: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/20.jpg)
More Directions
![Page 21: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/21.jpg)
How Matrix Forms
![Page 22: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/22.jpg)
Reconstruction with least square
![Page 23: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/23.jpg)
Efficiency
![Page 24: Case Study Computed Tomography (CT)](https://reader035.vdocuments.mx/reader035/viewer/2022062221/568134e0550346895d9c1541/html5/thumbnails/24.jpg)
Computed Tomography
冠状动脉