Noise and Single Slice Spiral Scanning
Effect of interpolation algorithm :
180º LI ? higher noise than axial (x 1.15)
same number of projections, + interpolation
can be shown to be ? ?2 x ?(2/3) x axial
360º LI ? lower noise than axial (x 0.83) uses twice as many projections than 180
can be shown to be = ?(2/3) x axial
See AAPM 1995 Summer School