See my reply. Scanned are generally just pictures, so obviously an ocr is the only way to go. However if you have contact with the document supplier and they do not understand how to make pdfs accessible and how to make comments editable etc, it might be easier for them to simply send you the original docx files that they made them with instead, or they will need to be using the paid for pdf Adobe suite of software to make them accessible. They could be using any old third party tool or word itself to make them and hence it would be fare easier to send them as word in the first place. From experience the only reason they site for using pdf is that they do not want people changing content, but in the case of a blind user, if they cannot create an accessible pdf, the use of word would seem to be a logical adjustment to make.
Brian

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