In the first step of the assessment, you must select the images that you want to use. At this stage, the window has the following appearance. You will need to select a short axis stack and two long axis perpendicular slices that pass through the centre of the mitral valve.
In the lower pane of the window, a list of thumbnails is shown. Each thumbnail represents a single image series. An image series is a collection of images that typically shows consecutive phases of the cardiac cycle. You can click on a thumbnail to select an image series, or you can click and drag to select several series at once. When a series is selected, its thumbnail is highlighted. You can click and drag on selected thumbnails to deselect the corresponding image series. The number of phases in an image series is shown in the bottom left-hand corner of the corresponding thumbnail.
In the upper pane of the window there is a three-dimensional view which allows you to compare the orientation and spacing of images. To compare two image series, click on one image thumbnail in the list and then hover the mouse cursor over another. Each 3D image has an outline that is the same colour as the corresponding highlighted thumbnail.
The 3D view allows you to understand how the different image series are related and helps you to check that short axis images are parallel. In addition, it is possible to check that you have selected all of the image series for the short axis stack. You can click and drag within the 3D display to rotate the view, and you can use your mouse wheel to zoom.
Note - If you have acquired the images using a scanning sequence that orders images in an unconventional way, you may find that a single image series contains many image slices. If this is the case, one image series in the thumbnail view will correspond to multiple image slices in the 3D view.
If two or more of the selected image slices are coplanar then only one of them can be displayed at any time. However, a symbol representing the number of coplanar image slices will be displayed at the corner of the image. You can click on this symbol to switch to the next image in the plane.
Before you can advance to stage 2, you must select all of the images that are required for analysis. Once you have selected the necessary images, click on the 'phases' button in the workflow to advance to the next step.