Talk:Computed tomography

Multidetectors

The rewording I suggested is not ideal, but "multidetectors", I believe, is ambiguous in a discussion that includes both SPECT and CT. Depending on the specific Anger camera that is used in SPECT, there commonly would be multiple photodetectors behind the spots in the crystal corresponding with holes in the collimator. Depending on how one thinks about that structure, it is either a group of detectors, or the whole crystal-collimator assembly is one detector. It's certainly not impossible — I think I remember seeing some — where there are multiple such groups on the same gantry, set far enough apart to collect multiple views concurrently and speed up the scan time.

As I understand it, having multiple detectors in spiral CT both is a matter of speed, and also of image quality as the geometry in a spiral scan is much more complex than the essentially sequential planar scan in SPECT. I wanted to be clear about this. At the moment, I am on my first partial cup of coffee, partial because I couldn't wait for the machine to finish a full cup. When I am less caffeine-deficient, I may attempt some sketches, which I think will be literal scanned sketches to be used as examples only. Do you, by any chance, have any graphics that might be redrawn if there's a permissions issue? Even without getting into image construction, I believe that the article addresses some significantly different multiple detector definitions and geometries that these should be visualized. Theoretically, I see no reason that in a transmission technique such as CT, rather than a endogenous generation technique such as SPECT, why there could not be multiple sources as well.

Howard C. Berkowitz 06:55, 22 August 2008 (CDT)