Fusion

An important part of the viewer is the ability to fuse together the CT and PET studies so as to see the radioactive take up on the anatomical background. If one releases the MIP button one sees:

The rightmost image is the fused image. It has been clicked up and the dual slider is placed under its control. Normally the dual slider controls the contrast and level, but in this case it changes the relative weight of the PET versus CT. The cursor has been placed upon the slider and it has changed to a double arrow for dragging right or left. Dragging to the far right will give 100% CT, while dragging to the far left will give 100% PET. It starts out in the center with equal weight to both modalities.

This particular study has MRI in addition to CT. By right clicking on the CT image, one can choose to see the MRI.

Here too one can change the relative weights of PET versus MRI by dragging the slider. However, since the structure of the MRI is closer to the PET, there is addition control. This may be useful if you are preparing a slide for a report. Go into Edit, Options to get

First of all you may choose a hot iron fused display in place to the blue one displayed. Second the Fusion factor has been reduced from 120% to 80%. This gives a softer fusion which might be easier to interpret. Each modality is given its position on the dual slider bar multiplied by the fusion factor. 100% would give exactly 50-50 in the middle. You can set the value to whatever is easiest to you to interpret the results. With 80% the image looks like

Another obvious change you could try is reduce the contrast of the PET image itself. To do this, click on the PET image and then grab the right hand side of the dual slider and drag it to the right, widening the slider bar.