Hypertensive Retinopathy

Systemic hypertension may be primary in etiology or may occur secondary to underlying systemic disease (including renal or cardiovascular dysfunction), endocrinopathy (including hyperthyroidism, hyperadrenocorticism, diabetes mellitus) or neoplasia (including lymphoma, multiple myeloma & phaeochromocytoma). Non-hypertensive, hemorrhagic retinopathy may also be associated with inflammatory, infectious and/or neoplastic disease. Ocular changes are often the presenting symptom of systemic hypertension. Blood-ocular barrier breakdown results in variable combinations of sub-retinal fluid leakage, (pre intra or sub) retinal hemorrhage &/or detachment, hyphema, visual deficits/blindness and/or secondary glaucoma. Neurological symptoms may additionally be present. Ocular symptoms are usually bilateral, however not necessarily symmetrical. Values indicative of hypertension are variable, however systolic pressures above 160mmHg in cats and 140mHg in dogs generally justify therapy, particularly when associated with clinical symptoms.