ROI_number

Hi,
thank you for this tool.

I have some difficulties when adding a new ROI into an existing RTstructure.

In fact, I looked at the code and when adding a new ROI, the ROI_number is set to ds.StructureSetROISequence +1. However, in the RT file I have downloaded from my PACS, ROI_number are not consecutive. For example they are foing from 2 to 17, then 19 and 63. So I have for example 17 initial ROIs, and if I add 2 more ROIs, numbers 18 and 19 are automatically attributed, and this generates a error message when I reimport the RT structure in my PACS because there are two "numbers 19".

I will try to get around the problem but one of my suggestion would be to propose to the user to add (or not) the ROI_number when calling the add_ROI function and at least to specify this problem in your readme file as it was very difficult to understand where was the problem.

Best

Fabien

Start at the add_ROI function mentioned in the issue and inspect how ROI_number is chosen from the existing StructureSetROISequence. Reproduce the case with non-consecutive ROI numbers such as 2–17, 19, and 63, then verify that adding ROIs does not create duplicates and that the resulting RT structure can be reimported.