I just happened upon your comment. It is amazing to me that NO ONE has commented to you about this. I have had the very same thing happen to me and I was in Nam 66-67. I seem to be doing fare now but have more blebs on the right lung at the bottom. My surgery was much later than yours ( last year)_
There has been some research done by the Air force and the document is there but I can't seem to retrieve it. I will continue because it is something that I believe that every Viet Vet need to know about.
Shuttsey