The difference in length, 3.1 to 3.0cm is minimal and can be put down to the Dr/Radiographer determining the edge of the cyst.

The difference with the other measurements, I would say, is that your earlier measurement of 1.6cm was made on a cyst which was tubular. Now, it has expanded by 0.4 and 0.6cm to 2.0cm width and 2.2cm depth, so it is slightly flattened now.

That is just my take on it, but the measurements are definitely showing expansion.

Hope that is easier to understand.

Oh, there are 2.54cm in an inch.

Dave.