What might be a potential complication of untreated hypertension on eye health?

Hypertensive retinopathy is a condition directly linked to untreated hypertension and signifies damage to the retina and its blood vessels due to high blood pressure. When hypertension is prolonged and uncontrolled, it can lead to changes in the retinal blood vessels, including narrowing, hemorrhages, and exudates. These changes can compromise vision and, in severe cases, can lead to permanent vision loss if the hypertension remains unmanaged.

The other conditions listed, while they can affect eye health, are not directly caused by untreated hypertension. Optic nerve atrophy may occur from various causes, but it is not specifically a result of hypertension. Color blindness is a genetic condition, unrelated to high blood pressure. Macular degeneration is mostly age-related and not directly caused by hypertension, although there may be some correlation related to overall vascular health. Thus, hypertensive retinopathy stands out as the most immediate complication of uncontrolled hypertension affecting the eyes.