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A comment on Godfrey Newbold Hounsfield, who revolutionized neuroimaging. Parent comment

Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by dreamcompiler on Saturday October 02, 2021 @04:21PM (#28731742)
Marching Cubes is only the visualization mechanism after you have the voxels. The real work is in reconstructing the 3D data [voxels] from 1D scans, and that typically uses the Radon transform:

https://en.wikipedia.org/wiki/Radon_transform

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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by AnimalMuppet on Saturday October 02, 2021 @06:09PM (#28732559)
Don't they really use Feldkamp-Davis-Kress cone-beam algorithm? (https://pubmed.ncbi.nlm.nih.gov/15305448/)

Because the x-ray sources are point sources, or close, so you get a cone beam.

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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by habi on Sunday October 03, 2021 @03:39AM (#28735301)
There’s a large amount of different reconstruction algorithms, some geared for speed, some geared for noisy data, some geared for quality. Wikipedia has a quick overview: https://en.wikipedia.org/wiki/Tomographic_reconstruction
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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by sandwall on Saturday October 02, 2021 @10:19PM (#28733989)
Later, that was developed in 1984; CT's use collimated fan beams
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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by AnimalMuppet on Saturday October 02, 2021 @10:29PM (#28734045)
Use? You mean currently? I thought they used cone beams, but I never worked on them directly...
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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by habi on Sunday October 03, 2021 @03:36AM (#28735281)
A fan beam is ‘just’ a more collimated cone beam.
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Re:Godfrey Newbold Hounsfield, who revolutionized neuroimaging by sandwall on Sunday October 03, 2021 @09:08AM (#28736906)
Yes, but this was only shown later -- The reconstruction algorithm for cone-beam was published in 1984 by research staff at Ford Motor Company. The Felkamp, Davis, and Kress algorithm was demonstrated as a natural extension of the fan-beam algorithm. -- first pencil beam, then fan-beam, finally cone-beam
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