Using Settings - Carestream Vue PACS MR Diffusion User Manual

9. Using Settings

The Perfusion Settings window allows you to change parameters related to the perfusion algorithm,
map parameters, clinical parameters, input state, ischemic regions, and tables.
To change parameters, click Settings
window to make your adjustments. You can change the following settings:
Algorithm-Related Settings
Setting
Deconvolution
Algorithm
Leakage
Advanced Leakage
Correction
sSVD Advanced
Settings
cSVD Advanced
Settings
oSVD Advanced
Settings
Map-Related Settings
Vue PACS MR Perfusion User Guide
AE9362 C
Vue PACS MR Perfusion User Guide - AE9362.docx
in the Perfusion ribbon. Use the Perfusion Settings
Description
Select a deconvolution algorithm.
•
sSVD—Standard Singular Value Decomposition.
•
cSVD—Circular Singular Value Decomposition. An sSVD algorithm with
a circular time curve. This method is stable with respect to delays in the
contrast material in the arterial input.
•
oSVD—Oscillating index Singular Value Decomposition. An iterative
cSVD method which reduces the Oscillating Index (OI).
Set the Leakage parameter to either Corrected or Uncorrected. Select
Uncorrected when you assume no leakage has occurred. When Leakage is set
to Uncorrected, the k2 map is not displayed, and all other map calculations take
no leakage into account.
When Leakage is set to Corrected, the Advanced Leakage Correction
parameter enables you to determine whether the k2 map will be normalized by
K1. This option is not selected by default.
Set regularization type and fraction for sSVD.
Regularization Type:
•
SV cutoff—Set to zero all Singular Values (SV) smaller than the cutoff
value.
•
Tikhonov—Set a threshold for applying the Tikhonov regularization
method.
Regularization Fraction:
Set the fraction of the highest Singular Value (SV) to determine the
regularization threshold.
Set regularization type and fraction for cSVD.
Regularization Type:
•
SV cutoff—Set to zero all SVs smaller than the cutoff value.
•
Tikhonov—Set a threshold for applying the Tikhonov regularization
method.
Regularization Fraction:
Set the fraction of the highest SV to determine the regularization threshold.
Set a regularization threshold for oSVD.
The oSVD method always uses a Wiener filter iteratively until the Oscillating
Index (OI) reaches a value lower than the regularization value.
Uncontrolled unless otherwise indicated
Unrestricted Internal Use
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