To begin, create the appropriate folder structure for the protocol. Navigate to the project's main folder and locate the program file. Double-click on the file to launch the software and display the program's code.
To launch the program, click anywhere on the editor window and click the green Run button on the top ribbon of the Editor tab. Click the open DICOM button in the bottom left corner to access the files directory. Navigate to the main project folder and find the original data.
Select the patient's folder to be analyzed and click Open. The images in axial, sagittal, and coronal views will appear on the screen. To examine the slices in a specific view, hover and scroll over them.
Use the crosshairs to display the location of the pointer at that moment. Using the sliders found in the bottom right corner of the program, adjust the brightness and contrast of the image. To analyze the coronary artery calcification, click the zero milligrams per milliliter phantom button.
Hover over the axial view and scroll until the zero milligrams per milliliter section of the phantom is visible. Position the cursor at the zero milligrams per milliliter phantom midpoint in the axial view. Observe the crosshairs in the sagittal and coronal views without moving the cursor.
Scroll through several slices until the crosshairs in the three views are centered on the zero milligrams per milliliter phantom. To generate a red cluster of circles in the axial view and a column of three points in the sagittal and coronal views, place a 10 by 10 point grid on the current and adjacent slices. If a phantom is unavailable or of poor quality, select the No Phantom button to use an aggregation of 10 sample phantoms and their corresponding weighting functions.
Then select an artery button to start tracing each of the four coronary arteries. Hover over the axial view. Scroll to navigate to either the proximal or distal end of the chosen artery and observe the shape of the artery in the slice.
To mark a circular artery, click on its center in the axial view and a five millimeter diameter point will appear, which will also be visible in the sagittal and coronal views. If the artery is more visible in the sagittal or coronal views, place a point there ensuring it aligns with the artery's center in the axial view. Quickly double-click in any of the three views to delete the suboptimal placed points.
Observe the bottom left area for a notification confirming the points deletion. If the shape of the artery is not circular in the axial plane, ensure the desired axial slice is in view and click the Draw ROI button. In the popup window, scroll to zoom in or out, and start tracing around the artery with single clicks.
To delete the previous point in the artery tracing, use the Backspace key while the ROI is open and close the ROI by double-clicking on the last or first point placed. Refine the closed ROI by dragging its perimeter points or double-clicking on the perimeter to add a point. Then lock in and redraw the ROI will appear at the bottom of the popup window.
Once satisfied with the current ROI, click the Lock-in button and close the pop-up window using the red button in the top left corner. To delete a locked-in ROI, double-click any perimeter points in the axial view of the main program window. Scroll through one slice in the axial view and repeat the procedure until the end of the chosen artery is reached.
After completing the tracing, re-click on the Arteries button to ensure no accidental points were placed. After tracing all four arteries, click the SWCS button in the bottom right corner to generate results. The bottom left area will show the progress and display Done Processing when finished.
Close the program window by clicking the red button. To access the results, open the files directory, navigate to the project's main folder and enter the metadata folder. Look for a folder with the same name as the original folder for the subject and find the file in the desired format.
Review the PDFs to obtain the final SWCS and Agatston score for the case and the weighting function used. The percentage difference between the Agatston score obtained from the program versus the commercial software is presented using the Bland-Altman plot.
