If the blood pressure is very high it can be called malignant hypertension and cause swelling of the macula and acute loss of vision. Otherwise hypertension can cause progressive constriction of the arterioles in the eye and other findings. Usually high blood pressure alone will not affect vision much, however hypertension is a known risk factor in the onset and/or progression of other eye disease such as glaucoma, diabetic retinopathy, and macular degeneration as well as blocked veins and arteries in the retina or nerve of the eye that can severely affect vision.