Hypertension is defined as systolic blood pressure (BP) exceeding 140mmHg and/or diastolic BP exceeding 90mmHg measured at least twice on separate days. About 90 percent of cases are due to essential hypertension, while the remaining cases are secondary to another disease, such as renal parenchymal disease or pheochromocytoma. There is also isolated systolic hypertension and isolated diastolic hypertension.
Hypertension occurs when pressure inside the blood vessels is too high. Many people do not experience any symptoms, so they may ignore their condition. Over time, however, the strain hypertension places on the heart and blood vessels can increase the risk of heart disease, stroke, and kidney damage. The condition often can be controlled through a combination of lifestyle changes and, in many cases, medication.
Hypertension is manifested within the eye as both hypertensive retinopathy and hypertensive ocular complications. Hypertensive ocular complications include retinal vessel occlusion, ocular ischemic syndrome, non-arteritic anterior ischemic optic neuropathy, internuclear ophthalmoplegia, cranial nerve palsy, nystagmus and midbrain syndrome, and amaurosis fugax and transient ischemic attack.
Stage 3 hypertension is very serious. This stage is characterized by a blood pressure reading of 180/110 or higher and needs immediate medical attention. The blood pressure shows a persistent elevation (systolic >180mm Hg; diastolic >110mm Hg) with target end organ damage. The damage to the heart may manifest itself in a strain or enlargement of the left ventricle. Kidney damage may show abnormal laboratory value readings that indicate inefficiency. The damage to the eyes could show up as small hemorrhages due to the sustained blood pressure in such small vessels. Stage 3 hypertension is immediately treated with antihypertensive medications.