When you say "saved" you mean you synchronised them from the computer to you iPod touch? If so, you'd lose those of you sync to another computer. If you took the photos with your device you should not lose them as iTunes should just back it up.
If you are still worried, I suggest you download iExplorer from macroplant(dot)com. It's free and works for both Windows and Mac.
After installing, connect your device; when iTunes opens, just close it. Open iExplorer then on the left pane you'd see folders. The photos should be there, you could just drag the folder to your Desktop to copy them off your device.
Hope this helps.