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Additional important information, Radiation therapy – Siemens EMOTION 16-Jun User Manual

Page 482

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482

Radiation Therapy

Additional Important Information

HU values

The HU values are of crucial importance for the therapy
planning systems of radiation therapists!

• With huge objects, the CT value is independent of

the kernel. With smaller objects, edge effects pro-
duced by the kernel influence the HU values as well
as the scanning. Feed and collimation do not have
any influence.

• An extended FoV of 800 mm means that only 500

mm are scanned, the rest will be interpolated.

• The effect on the HU values of having carbon plate

tagged additionally to the patient table should be
negligible and not measurable.

• CARE Dose 4D does not have any effect on the HU

values.

• HU values and the conversion of the electron densi-

ties depend on the applied spectrum, e.g. kV, prefil-
tration(kV, prefiltration, etc.)

• HU values depend on the use of the online bone cor-

rection (PFO).