What are the chances of hypernasal speech following adult adenoidectomy?

[phatadenoids]

I've had a recurring ear problem for the past 7 years, and my new ENT doctor has identified the cause of the issue. They say it's that my Eustachian tubes are blocked by enlarged adenoids.

I've extensively searched for information regarding adenoidectomies, but all of the information I find is on children. I'm prepared for a change in vocal quality due to a different amount of air exiting through the nose, and I'm okay with this.

I've read of the condition of hypernasal speech, however. I read different figures stating that the chances are 1/1500, and 1/10000. Either way, this sounds quite rare. The issue is that almost exclusively, discussion of adenoidectomies focuses on children.

Do the implications of the surgery (including, but not limited to, the degree of voice/pitch change, the likelihood of developing hypernasal speech) change because I'm an adult?

The surgery will be 3/4 months away, so I have a lot of time to figure all of this out. I also assume that these issues will be discussed in the preliminary appointment, but I'd like to get on top of this and be fully aware of the implications well in advance.

Thank you!