Operating instructions

34
Scan and Reconstruction
Head Kernels
For soft tissue head studies, the standard kernel is
H40s; softer images are obtained with H30s or H20s,
H10s, sharper images with H50s. The kernels H21s,
H31s, H41s yield the same visual sharpness as H20s,
H30s or H40s, respectively. The image appearance,
however, is more acceptable due to a "fine-grained"
noise structure; quite often, the low contrast detect-
ability is improved by using H31s, H41s instead of
H30s, H40s.
High Resolution head studies should be performed
with H50f, H60f (e.g. for dental and sinuses). It is man-
datory to position the area of interest in the center of
the scan field.
Child Head Kernels
For head scans of small children, the kernels C20s,
C30s (e.g. for soft tissue studies) and C60s (e.g. for
sinuses are provided) should be chosen instead of the
"adult" head kernels H20s, H30s and H60s.