Real World Value Mapping (RWVM)

[Bijesh B]

Hi All,

This is regarding the Real World Value Mapping.
Can anybody tell me if a RWVM can have BOTH "RealWorldValueIntercept &
Slope" AND "LUT Data".
If both can co-exist, then which one takes the preference? LUT data?

Thanks in advance...

Best Regards,
Bijesh

[David Clunie]

Hi Bijesh

Bijesh B wrote:

> This is regarding the Real World Value Mapping.
> Can anybody tell me if a RWVM can have BOTH "RealWorldValueIntercept &
> Slope" AND "LUT Data".
> If both can co-exist, then which one takes the preference? LUT data?

I presume that you are referring to the RWVM IOD and not the
functional group macro as used in the enhanced image IODs,
though the same general principle applies.

Within a single item of the Real World Value Mapping Sequence, either
the linear parameters or a LUT may be present but not both in
the same item.

However, one could construct a single instance that replicated the
same (or an overlapping) list of images that had more than one item
in Referenced Image Real World Value Mapping Sequence and overlapping
pixel value ranges that were mapped, and hence more than one alternative
path.

In such cases neither takes "priority" per se; these would be mappings
to different "units".

For example, the same pixel data values in PET could be mapped
"simultaneously" to counts, activity concentration (MBq/ml) and
different forms of SUV (SUVbw in g/l, SUVlbm and SUVbsa) to give
an extreme example.

David

[Bijesh B]

Thanks David!