Hi,
So in the "Title" column of your values, instead of 0, 1, 2, etc enter translation keys like that:
POLLPRESSURE_0
POLLPRESSURE_1
POLLPRESSURE_2
...etc...
Then, edit your language file via the Languages tab of the HikaShop configuration and enter such translation override:
POLLPRESSURE_0="<img src='http://mywebsite.com/myimage0.jpg'/>"
POLLPRESSURE_1="<img src='http://mywebsite.com/myimage1.jpg'/>"
POLLPRESSURE_2="<img src='http://mywebsite.com/myimage2.jpg'/>"
...etc...
Then, you'll see on your frontend that the numbers will be replaced by the images.