Open a DICOM file. Open the File menu and select Open. Browse for a DICOM file (.dc3, .dcm, .dic, or no extension) and click OK
Press the Select All button to select all the frames. In the Frame Import Options, choose Import frames as layers. Apply any other settings needed then click OK.

You should now have each frame as layers. Select all the layers by pressing Alt+Ctrl+A or going into the Select menu and choosing All Layers.

Open the Animation window by going into the Window menu and selecting Animation.

In the Animation pallet, click on the
button located near the top right to open the flyout menu. In the flyout menu, select Make Frames From Layers.

If the Animation window is not in Frame view, press the
button to convert the animation into a frame animation. If it's already in frame view, you can skip this step.

Now we need to set how many times it should loop. Click on the bottom right menu to select how the animation should loop. To have the animation loop forever, select Forever.

To save the animation as an animated GIF file, use the Save for Web & Devices tool. To open the Save for Web & Devices tool, press Shift+Ctrl+S or open the File menu and select Save for Web & Devices. In the Save for Web & Devices tool, Select a GIF preset and modify the settings if necessary. Click the Save button when you are ready to save.

