Recently diagnosed and have a question

I ended up on the ICU 3 weeks ago without ever having a blood sugar issue. My blood glucose was unreadable even from a lab test. Since the second day in the hospital I noticed my vision has been blurry. The doctor and diabetic educator said within 6 weeks if I get and keep my blood sugar under control (which I have) that it should be back to normal.

My question is if this is common and how likely is this to be true? I was told for the short term to get some cheater glasses to hold me over as my near vision is almost too blurry to read anything. I'm asking here because I cannot find any resources that back up what the doctor and educator told me and I just want to have peace of mind on this topic.

Oh and it should be noted that they still have not diagnosed what type I am. Currently undergoing testing to sort that out.