Comaprision of values in chart field cell

I have a situation that I could use help with. I've thought about every scenario possible and have ran out of ideas. Scenario: The user changes, make additions, or removes information in the system. Those changes are color coded based on what the changes are. However the 'Other' field in the chart can display - changes, additions, and removals. The 'other' field is a free range text box (basically they can put whatever which sucks), but is there any way to display the differences between the 2 sections to compare the 'old value' and 'new value' within the 'other' section.

•USER CAN ENTER ANY TEXT IN FIELD

•THIS IS A STRING

•PERSON VIEWING THIS CHART NOW HAS TO COMPARE OLD VALUE AND NEW VALUE WITH THE EYE, THERE IS NOTHING ELSE TO LET THE USER KNOW OF THE DIFFERENCES