Hi,
I'm 45, been T1 for 34 years and suffer from retinopathy and glaucoma. I have had 3 vitrectomies in the past and I have flown from the UK to the US many times since the operations. I have never had any problems with my eyes during or after flights. I understand that some people suffer with "dry" eyes due to the climate in the aircraft. This can be a bit worse if you have existing eye problems but you can use eye drops to ease the feeling during the flight. I have been told by my consultant that flying will not cause any problems with the retinopathy, but to avoid flights within the first 2 months following an operation. Ask your eye specialist or optician for their opinions.
Hope that helps.
MB