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3.2.7 Kappa

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  • 35

This option is only active if the "smoothing" option is turned on AND the "smoothing_algorithm" is set to anything but "gaussian" (PM, area, or rician). It is a floating point value.

This parameter, in a way, defines the strength of the image gradient to be improved. Gradient values below this parameter will be smoothed and gradient values above it will be strengthened.

The value "35" is chosen based on standard DWI signal values up to 2000. If the user's scaling is different than this parameter should be scaled accordingly.