Hypertensive retinopathy refers to fundus changes occurring in patients suffering from systemic hypertension. Hypertensive retinopathy is a spectrum of microvascular changes that are associated with high blood pressure. Hypertensive retinopathy represents the ophthalmic findings of endorgan damage secondary to systemic arterial hypertension. As well as retinal changes, hypertension can also damage the choroidal circulation and is responsible for optic and cranial neuropathies.
Hypertension is a worldwide problem that affects approximately 1 billion people worldwide, and is the single most important modifiable risk factor for stroke. Even milder degrees of blood pressure elevation pose increased risk for cardiovascular events. High blood pressure affects not only the heart, kidneys, brain and large arteries but also the eyes. Retinal, choroidal and optic nerve circulations undergo pathological changes, resulting in clinical signs referred to as hypertensive retinopathy, hypertensive choriopathy, and hypertensive optic neuropathy.
The severity of retinal microvascular changes can predict the mortality of hypertensive patients and devised a four-grade classification system for hypertensive retinopathy, with increasing severity based on arterial characteristics and retinopathy. This classification system is known as the Keith-Wagner-Baker system and it ranges from grade 1 to grad 4. Hypertensive retinopathy includes two disease processes. The acute effects of systemic arterial hypertension are a result of vasospasm to auto regulate perfusion. The chronic effects of hypertension are caused by arteriosclerosis and predispose patients to visual loss from vascular occlusions or macro aneurysms.
High blood pressure results in a series of pathophysiological changes in the retinal circulation. The initial response is vasospasm as well as generalized arteriolar narrowing, this is in response to elevated luminal pressure. Chronic arteriosclerotic changes then develop, such as intimal thickening, media-wall hyperplasia, and hyaline degeneration. These changes are clinically seen as focal and diffuse narrowing of the retinal arterioles, opacification of the arteriolar wall (silver or copper wiring), and compression of the venules by arterioles at their common adventitial sheath (arteriovenous nipping or nicking). At a much higher blood pressure, the blood-retinal barrier breaks down, resulting in lipid exudation (hard exudates), hemorrhages, and nerve fiber layer infraction (cotton-wool spots) (exudative stage ). In patients with severe high blood pressure, disc swelling (papilledema) can occur owing to optic nerve ischemia and concomitantly increased intracranial pressure.
*Management
The treatment for hypertensive retinopathy is to correct the underlying condition by normalizing the blood pressure. This causes resolution of the fundus abnormalities over a period of weeks to months in eyes with grade 3 to 4 changes, but often does not affect the changes seen with grades 1 and 2 hypertensive retinopathy. Treatment of malignant hypertensive retinopathy, choriopathy and optic neuropathy consists of lowering blood pressure in a controlled manner. If the decline is too rapid there is impairment of autoregulation and this can lead to ischemia of the optic nerve head, brain and other vital organs. The management of malignant hypertension is considered a medical emergency. Untreated, the mortality rate is 50% at 2 months and 90% at one year. Drugs that are commonly used in the outpatient setting to reduce blood pressure include angiotensin converting enzyme inhibitors, calcium channel blockers, and diuretics. Other less commonly used medications include alpha adrenergic blockers, direct vasodilators, and central a2-adreneric agonists.
is is a project initiated by
and friends to give back to the society the knowledge and skill acquired through the Optometric Studies in Kwame Nkrumah University of Science and Technology, Ghana.It is an outreach system where we visit the less privileged communities to offer free eye screening services and education to the people within the community
AIMS AND OBJECTIVES
To reduce or prevent vision loss through diseases such as glaucoma, cataract and refractive errors.
To enlighten the majority of the Ghanaian population about the importance of proper visual care.
To conscientize people on the need for regular eye checks
To get more people to have their wards screened within the Critical periods of a Child’s Vision Development; thus from ages 3 to till about 10 years.
To help the blind and people with low vision live a better life within the society through education of the general public to stop stigmatization.
To help in the fight of extreme poverty that puts the health of people at risk
Our greatest gratitude goes to
and
for helping to make the aims and objectives of
a reality.