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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.
In emergency examinations, kernels H22s, H32s, and
H42s can be used because they allow fast reconstruc-
tion (FR) and easy patient positioning (50 cm FoV). To
ensure best performance, special online bone correc-
tion (PFO) is not used.
High Resolution head studies should be performed
with H50f, H60f (for example, for dental and sinuses).
It is essential to position the area of interest in the cen-
ter of the scan field.
For a better gray-white brain tissue differentiation use
the H37s, H38s or H47s kernel (Emotion 16-slice con-
figuration only).
Child Head Kernels For head scans of small children, the kernels C20s,
C30s (for example for soft tissue studies) and C60s (for
example, provided for sinuses) should be chosen
instead of the "adult" head kernels H20s, H30s and
H60s.