Hypertensive retinopathy results from chronic primary hypertension, malignant hypertension, or eclampsia. If untreated, it can lead to retinal detachment. Plus, retinal vessel damage suggests that the patient has suffered damage to other organs, as well.

Pathophysiology

With retinopathy, retinal changes are categorized according to the severity of the vessel damage. Retinal arteriolar narrowing and increased dias­tolic blood pressure are directly related.

Grade I retinal changes may occur when a patient has mildly elevated diastolic blood pressure, about 90 mm Hg. These retinal changes include vascular spasm and arteriolar constriction.

Grade II retinal changes occur when a patient has sustained elevated diastolic blood pressure of more than 100 mm Hg. These retinal changes include localized and generalized arteriole nar­rowing at arteriovenous junctions.

If the patient’s hypertension is left untreated and his diastolic blood pressure remains above 100 mm Hg, he may experience grade III retinal changes. Occlusion of the retinal arterioles may cause superficial, flame-shaped hemorrhages and small, white areas of retinal ischemia called soft exudate or cotton wool spots. Hard, yellow ­white exudate may produce a star-shaped figure around the macula.

Further untreated hypertension can lead to grade IV retinal changes. The occluded arterioles cause the optic disk to become congested and edematous, leading to papilledema (swelling of the optic nerve head). Papilledema causes the optic disc margins to become blurred and indistinct. Without treatment, this condition can lead to blindness.