differentiate between a ISBLANK and an actual empty cell?

Is there a way to differentiate between a ISBLANK and an actual empty cell?

I have a formula running from rows 1 to 11....where based on a condition the contents of the cell change to some value or become blank...by using double quotes " "...

Now i want to check whether there is contents in cells from row 1 to 11 , like is it orginally blank or made blank by by using double quotes " "...

ISBLANK does test for an empty cell:

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