Gantry rotation time

Current MDCT scanners have sub-second gantry rotation times. Reducing the scan rotation time from 1.0-0.5 s will halve the time taken to perform... 

Now in 2006, 64 row CT scanners are being installed i diich allow 64 x 0.6 mm slices to be obtained in a single gantry rotation with gantry rotation times decreasing to 0.33 s. The progression of data acquisition can be depicted by displaying the... 

With this approach, constant temporal resolution equivalent to a quarter of the gantry rotation time is achieved in a centered region of the scan field of view. For trot= 0.33 s, the temporal resolution is t t/4 = 83 ms, independent of the patients heart rate. 

Fig. 1.5a,b. Schematic illustration of a dual-source CT (DSCT) system using two tubes and two corresponding detectors offset by 90°. A scanner of this type provides temporal resolution equivalent to a qiuirter of the gantry rotation time, independent of the patient s heart rate. In a technical realization, one detector (a) covers the entire scan field of view with a diameter of 50 cm, while the other detector (b) is restricted to a smaller, central field of view... 

SORGE 2001), which provide a temporal resolution up to half the gantry rotation time per image in a sufficiently centered region of interest. The 16-slice and 64-sHce CT systems offer gantry rotation times as short as 0.4 s, 0.37 s or even 0.33 s. In this case, temporal resolution can be as good as 200 ms, 185 ms or 165 ms. 

The major improvements of 4-sHce to 64-slice scanners include improved temporal resolution due to shorter gantry rotation times, better spatial resolution owing to sub-millimeter coUimation and considerably reduced examination times (Flohr and Ohnesorge 2001 Flohr et al. 2003b) see Fig. 1.16. 

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