To stop these vessels from proliferating, doctors must stop the release of the vasoproliferative substance. This is acheived by lasering the retina that is producing it. Unfortunately, the damaged retina is no longer functional. Even if a patient is newly diagnosed and has no symptoms of diabetes, they would still want to have a thorough baseline exam from which future exam results can be compared. Long term, uncontorlled hypertension causes this ratio to change.
Hypertension causes the harder arteries to constrict and to compress the more flacid veins.
At worst case, the pressure by the central retinal artery on the central retinal vein becomes too great and chokes off the blood supply to the retina. Blood begins to back up in the eye and the retina begins to starve for oxygen and dies within minutes. In some cases, the eyes can warn of impending stroke or aneurysm. If these are noticed in a patient with a history of hypertension, the patient must be seen immediatel by their primary physician. The take home message from this is that monitoring blood pressure, and blood sugar are very important.