CT scan : invention to development

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 CT scan :-



A commonly use word in medical field. It takes x ray imaging to a step away from 2D to 3D imaging.
When We are going to discuss conventional x ray imaging we take only a plain radiograph of a 2D plane where as we talk CT scan it is 3D study of an object or human body in multi sliced form.

CT invention - 

First commercial viable CT scanner designed by Sir Godfrey Newbold Housfield in 1971 in london, to over come the visual representation challenges in radiography and convention tomography.

Basic principal of CT - 

The basic principle behind CT is that the internal structure of an object that can be reconstructed from multiple projection of object. To carry out the reconstruction the ,u (mu) of the object is base. 
Where mu is linear attenuation coefficient.

Various principle parameters in CT scan - 

(1)slice   (2)matrix 
(3)pixel   (4)voxel 
(5) CT number (6) window
(7) pitch
Note - we describe these parameters in another part 

CT generations - 

Ct scanners have gone through various design changes since 1971 
These changes are describe in different different generations.
(1) first generation - translate rotate system
(2) second generation - rotate translate system 
(3) third generation - rotate rotate 
(4) fourth generation - rotate stationary
(5) fifth generation - electron beam CT
(6) sixth generation - helical ct 
(7) seventh generation - MDST

We discuss these generation deeply in next part...
     
Source - wikipedia , K thyalan book , s.k. bhargav  book 

                            Thanks...👍👍🙏

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