Use regular expression to return 5 words before and after target word.

[nilamo]

I think the word "diagnosis" is unimportant here.  Just scrape all the codes from the notes.  It's a well defined format, and should be easy to get.

I don't know anything about it, but yours have all been "R[number][number].[number]", which is a regex that would look like R\d{2}\.\d.  Trying to parse the notes to get codes that happen to be near a word seems ridiculous, when you can just easily go straight to the codes.