Windmill artifacts analysis in MSCT

Abstract

One of the most important advantages of the novel multi slice CT (MSCT) with increased number of slices is the ability to reduce the scan time. However, does the increased number of slices in the MSCT enforce us to reduce the pitch, in order to avoid windmill artifacts, hence preventing us from decreasing the scan time? In this work we address this issue along with other aspects of the windmill artifacts. We study the dependence of the windmill artifacts, their strength and frequency, on the number of slices and on the pitch. The study demonstrates, that when retaining constant bed speed while increasing the number of slices, the intensity of the windmill artifacts is reduced significantly. Images of scans performed with the same pitch, yet with various number of slices are compared. It is observed, that the intensity of the windmill artifacts is similar, independent of the number of slices. The frequency of the artifacts however, increases with the number of slices. The study concludes that updating a clinical protocol performed with a low number of slices MSCT, to a similar protocol performed with high number of slices MSCT, the same pitch can be used attaining better IQ. Scanning with the same pitch using wider coverage enables an advantageous shorter scan time in novel MSCT.