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Data Accuracy Control

To produce a high quality image we need both accurate volume data and good rendering techniques. Several papers have explored the effect of scan parameters, such as collimation, table increment(pitch), and reconstruction interval on the accuracy of the data produced [2], [4].

Brink et al. showed that for contrast material-enhanced vessels, a decrease in collimation from 2 mm to 1 mm resulted in an increase in noise. Also, the noise is doubled when collimation is decreased from 3 mm to 2 mm. It makes almost no difference in the final image whether 0.5 mm or 1.0 mm reconstruction intervals are used. A pitch of 2 is marginal for 2 mm collimation. Accurate data for analyzing renal artery stenosis is best depicted with 3 mm collimation, 2 mm - 4 mm pitch (table increment) and 1 mm reconstruction interval.



liao naiwen
Thu Dec 12 16:06:02 EST 1996