8/12/2019 What is CT ?

1/26

Computerized Tomography[ Computerized Axial Tomography ]

CT scanners or CAT scanners

D. J. McMahon 2014 rev 140219

8/12/2019 What is CT ?

2/26

Tomography :

an image from many slices (Greek: tomos= slice)

Digital geometry processing is used to generate athree-dimensional image of the inside of the body

from a large series of two-dimensional X-ray

images taken around a single axis of rotation.

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=QeRN_lZ4En9JHM&tbnid=THWbtodY9oinEM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.stlukeshouston.com%2FOurServices%2FDITR%2FCT-Scan.cfm&ei=a2ocUbgex8qtAdXQgdgM&bvm=bv.42452523,d.aWc&psig=AFQjCNFdFYtCjztkhYQnKWQ7v4JoAmu9Vw&ust=1360903130860988

8/12/2019 What is CT ?

3/26

Individual slice data is generated using an X-ray

source that rotates around the patient; X-ray

sensors are positioned on the opposite side of thecircle from the X-ray source. These sensors use

scintillation systems based on photo diodes.

Many data scans are progressively taken as the

body is gradually passed through the gantry. The

images are combined together by mathematical

procedures known as tomographic reconstruction.

Contrast between soft tissues can be increased by

injection of iodine-based solutions.

8/12/2019 What is CT ?

4/26

Evolution of CT scanning -

Increased beam size, and increased number of detectors.

Most current installations are third and fourth generation.

8/12/2019 What is CT ?

5/26

http://www.youtube.com/watch?v=M-4o0DxBgZk&feature=PlayList&p=BB3FA78509EB5D8F&playnext=1&playnext_from=PL&index=8

http://www.youtube.com/watch?v=lmn7OERw3iA

http://www.youtube.com/watch?v=M-4o0DxBgZk&feature=PlayList&p=BB3FA78509EB5D8F&playnext=1&playnext_from=PL&index=8http://www.youtube.com/watch?v=lmn7OERw3iAhttp://www.youtube.com/watch?v=lmn7OERw3iAhttp://www.youtube.com/watch?v=M-4o0DxBgZk&feature=PlayList&p=BB3FA78509EB5D8F&playnext=1&playnext_from=PL&index=8http://www.youtube.com/watch?v=M-4o0DxBgZk&feature=PlayList&p=BB3FA78509EB5D8F&playnext=1&playnext_from=PL&index=8http://www.youtube.com/watch?v=M-4o0DxBgZk&feature=PlayList&p=BB3FA78509EB5D8F&playnext=1&playnext_from=PL&index=8

8/12/2019 What is CT ?

6/26

More detectors and smaller detectors to give better resolution

Enhanced image data can be reconstructed thru algorithms

8/12/2019 What is CT ?

7/26

64-slice CT unit -

http://upload.wikimedia.org/wikipedia/commons/2/23/64_slice_scanner.JPG

8/12/2019 What is CT ?

8/26

T X-ray tube

D X-ray detectors

X X-ray beam

R Gantry rotation

8/12/2019 What is CT ?

9/26

http://www.youtube.com/watch?v=cjtHNxf01tQ

http://www.youtube.com/watch?v=JfEHvZ6ARdQ

http://www.youtube.com/watch?v=2CWpZKuy-NE

CT de-install -

Open CTs running -

http://www.youtube.com/watch?v=cjtHNxf01tQhttp://www.youtube.com/watch?v=JfEHvZ6ARdQhttp://www.youtube.com/watch?v=2CWpZKuy-NEhttp://www.youtube.com/watch?v=2CWpZKuy-NEhttp://www.youtube.com/watch?v=2CWpZKuy-NEhttp://www.youtube.com/watch?v=2CWpZKuy-NEhttp://www.youtube.com/watch?v=JfEHvZ6ARdQhttp://www.youtube.com/watch?v=cjtHNxf01tQ

8/12/2019 What is CT ?

10/26

Toshiba Aquilion - 80 detectors, 160 slices

http://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-

ct-prime-landing&utm_medium=plumb&utm_campaign=promo

http://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://medical.toshiba.com/products/ct/aquilion-prime/index.php?utm_source=quick-link-ct-prime-landing&utm_medium=plumb&utm_campaign=promohttp://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=Wb3_HSGbi90N5M&tbnid=F-6JsinorxoZrM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.medgadget.com%2F2012%2F08%2Ftoshibas-aquilion-rxl-ct-workhorse-cleared-in-u-s.html&ei=AG8cUfrWCpT_qQGzyoHoAg&bvm=bv.42452523,d.aWc&psig=AFQjCNE-z6twu8qwAq-o94NbFWDHrVDrbg&ust=1360904253749599

8/12/2019 What is CT ?

11/26

Specifications First CT Scanner(circa 1970)

State of the Art CTScanner

Time to acquire one CT image: 5 minutes 0.5 seconds

Pixel size: 3 mm x 3 mm 0.5 mm x 0.5 mm

Number of pixels in an image: 6,400 256,000

Early scan, ~1975 Scan, ~2003

8/12/2019 What is CT ?

12/26

Siemens Definitionscanner: Dual-source CT

Two x-ray tubes are operated at different tube potentials: one at alow energy (e.g. 80 or 100 kV), and the other at a high energy (e.g.140 kV). Different tube energies allow for differentiation between

materials such as iodine, calcium and uric acid, and is used todistinguish bone or iodinated contrast material, as well as thevisualization of blood perfusion.Dual-energy CT can also be used to identify the composition ofmaterials in the body, and to identify renal stone type or to detect

uric acid deposits in joints.

8/12/2019 What is CT ?

13/26

8/12/2019 What is CT ?

14/26

8/12/2019 What is CT ?

15/26

8/12/2019 What is CT ?

16/26

Typical CT study of a skull :

http://upload.wikimedia.org/wikipedia/commons/e/ed/CT_of_brain_of_Mikael_H%C3%A4ggstr%C3%B6m_large.png

8/12/2019 What is CT ?

17/26

Three-dimensional CT scanning:

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=5_1_w-t0HolswM&tbnid=0oJF30XPd1akxM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.physicscentral.com%2Fexplore%2Faction%2Fscans-1.cfm&ei=zFkcUeuiF4izrQHG3oDwCw&bvm=bv.42452523,d.aWc&psig=AFQjCNGMphHKOVnDb0mBwu1aFPJT2IGPxA&ust=1360898155301571

8/12/2019 What is CT ?

18/26

pixels voxels

http://localhost/var/www/apps/conversion/tmp/scratch_3//upload.wikimedia.org/wikipedia/commons/b/bc/Voxels.svghttp://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=3SW_VWNKM64zlM&tbnid=vTWo2OQePzzPzM:&ved=0CAUQjRw&url=http%3A%2F%2F24flinching.com%2Fword%2Fheadline%2Fa-pickle-of-pixels-pushing-the-boundaries-of-the-tiny-square%2F&ei=lXMcUcX-KYnwiwKYp4GQBQ&bvm=bv.42452523,d.cGE&psig=AFQjCNGXdxuLp4aEoWr9DuQ1yfDZhaqjyw&ust=1360905459077146http://localhost/var/www/apps/conversion/tmp/scratch_3//upload.wikimedia.org/wikipedia/commons/b/bc/Voxels.svghttp://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=Jm-w0mq86coUyM&tbnid=RPI0aN_dmwc1QM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.oculist.net%2Fdownaton502%2Fprof%2Febook%2Fduanes%2Fpages%2Fv2%2Fv2c025.html&ei=WXQcUdnzHqvFiwLWyoGQDw&bvm=bv.42452523,d.cGE&psig=AFQjCNGvpo74j_OP1-OagD7UVa4MnNwrWA&ust=1360905657851761

8/12/2019 What is CT ?

19/26

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=39L5Q4l_UwL97M&tbnid=7_le5nW5auSvQM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.flickr.com%2Fphotos%2Freaxis%2Fpage5%2F&ei=JngcUcDtK6OBiwLBm4GoCg&psig=AFQjCNGvpo74j_OP1-OagD7UVa4MnNwrWA&ust=1360905657851761http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=5FHgmx1p5KH8AM&tbnid=MWkrxlcSlWvZ1M:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.mccauslandcenter.sc.edu%2Fmricro%2Fmricro%2Frender%2Findex.html&ei=yHccUdj9KrCUigLpvYFI&psig=AFQjCNGvpo74j_OP1-OagD7UVa4MnNwrWA&ust=1360905657851761

8/12/2019 What is CT ?

20/26

http://upload.wikimedia.org/wikipedia/commons/4/4a/Ct-workstation-neck.jpg

8/12/2019 What is CT ?

21/26

Revealing bone densities and vessels by manipulation of the data -

http://upload.wikimedia.org/wikipedia/en/5/54/Venesreconstruction.JPGhttp://upload.wikimedia.org/wikipedia/commons/3/3d/Bonereconstruction.jpg

8/12/2019 What is CT ?

22/26

www.radiologyinfo.org/en/photocat/photos_pc.cfm?image=AbdoPelvMovie.jpg&pg=bodyct

Two views of a femoral fracture -

http://www.radiologyinfo.org/en/photocat/photos_pc.cfm?image=AbdoPelvMovie.jpg&pg=bodycthttp://www.radiologyinfo.org/en/photocat/photos_pc.cfm?image=AbdoPelvMovie.jpg&pg=bodyct

8/12/2019 What is CT ?

23/26

How much ??

4-slice scanner: $85,000 - $115,000

16-slice scanner: $145,000 - $225,000

64-slice scanner: $250,000 - $450,000

Service contracts: $100,000 - $135,000

8/12/2019 What is CT ?

24/26

CT tube replacement: $50,000 - $100,000

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=EaodYhr3ykPdfM&tbnid=yiFLgrGQ_J3NrM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.xrayglobal.com%2Fx-ray_products%2FVarian_CT_Scan_Tube.html&ei=Bl8cUfT2Foi9iwLEg4DwCA&bvm=bv.42452523,d.aWc&psig=AFQjCNGMphHKOVnDb0mBwu1aFPJT2IGPxA&ust=1360898155301571

8/12/2019 What is CT ?

25/26

Major players in CT scanners:

G.E. Medical ( GEMS)

Philips

Siemens

Toshiba

8/12/2019 What is CT ?

26/26

Major players inCT service and tubes:

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=4jTywsmGb0C3MM&tbnid=wCDcPh-hhfiHRM:&ved=0CAUQjRw&url=http%3A%2F%2Fradiationoncologymarketplace.com%2FListing%2FIndex%2FExternal_Beam_Radiation_Therapy%2FAccelerators%2F3708%2F11&ei=hzYdUf-7KI3YyAHurICIDg&bvm=bv.42452523,d.aWc&psig=AFQjCNERSFzISCYQUZM4xZb4urgiT52kRw&ust=1360955332016254http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=PJVDIU40rkOewM&tbnid=kqnzS-CC8n1yHM:&ved=0CAUQjRw&url=http%3A%2F%2Frsnabuyersguide.com%2FListing%2FCompany%2FRadiography%2FCameras__Camera_Systems%2F1129&ei=ETYdUdWEN6GFyQGd0YCQDQ&bvm=bv.42452523,d.aWc&psig=AFQjCNGYktht0DT_7cAW4IMkr-6OZp-Emw&ust=1360955238850696