Users set limits that determine whether a scan gets a Pass or Fail result. This section explains how to set the limits.
After data is uploaded to and processed by the Image Owl servers, two nominal processing results, 'Result' and 'Status', are returned immediately. They can be seen on the image of the 'Phantom scans' page shown below. In this section we will be concerned with the Result.
The Result is Pass-Fail and depends on whether or not the study parameters fall within limits set by the user. The Status of the scan will be Finished if the data is processed successfully, otherwise it will be Error. When the Status is Error, processing of the data failed and no study is generated. Further investigation into why processing failed is required.
Shown below is a sample of three scans from the 'Phantom scans' page. The third scan has a 'Status' of Error, and no study was generated. The first scan has a Result of Pass, and the second has a Result of Fail.
Below is a snapshot of a study. The reason a scan gets marked as Fail is that one or more of the study values falls outside of user-set Pass-Fail limits. Values that fall outside of the limits are shown in red on the study page. In the example below SNR, Max dist., and Max distortion X all fell outside of the limits.
Changing Pass-Fail limits by editing the Card
In the study data snapshot above, note the line in the header that says "CLONE 121: SYSTEM PHANTOM CARD". The pass-fail limits for study data results are set on a "card", in this case card 121. Clicking on the "Cards" link in the left hand menu will bring you to a list of cards for the posts you have set up. There is a card for each post, and the pass-fail limits can be customized on each card where they are then applied to the study data for the post associated with that card.
Below is a snapshot of the page that appears when you click on the "Cards" link in the left hand menu. Every customer will see only the cards attached to posts they have created. There are three options available for each card: Edit, Build CardItems, and Clone. The "Edit" option allows you to change the name of the card from the nominal, obscure "Clone 121: System Phantom Card" i.e., to something descriptive and useful like the name of the post the card is associated with, for example "Phantom Lab 3d MPRAGE". To change the name of the card click on the "Edit" link and type in the new card name as well as any descriptive notes in the appropriate edit boxes, and then click the "Change" button.
To change Pass-Fail limits, click on the "Build CardItems" link.
After clicking on the "Build CardItems" link you will see a list of study data parameters as shown below. To edit the Pass-Fail limits for a particular study parameter click on the name of the parameter, for example if you want to edit Pass-Fail limits for SNR, click on "SNR".
After clicking on the name of the study parameter whose limits you want to edit, you will see the card entries for that parameter (SNR in the example below). The limits are found toward the bottom of the page. In this case the limits are 150, 130, and 90 for Upper, Center, and Lower, respectively. To edit the limits simply check the "Edit limits" box, enter the new limits, and click the submit button on the bottom of the page. The new limits will be applied to Pass-Fail testing of all future scans. They won't be applied retroactively to past scans.