By Dr S.S. Gill
Ipoh Echo’s EYE HEALTH series continues with Consultant Eye Surgeon Dr S.S. GILL talking to us about effects of hypertension on the eyes.
The World Health Organisation estimates that raised blood pressure results in 7.5 million deaths worldwide. Globally, more than 1 billion people suffer from hypertension which is also called high blood pressure. It is called hypertension because the force of the blood pressure against the walls of the blood vessels (arteries) is high for a prolonged period resulting in it eventually causing health problems such as heart disease, kidney disease, hardening of the arteries, strokes and eye damage.
WHAT HAPPENS IN THE EYES?
The nerve tissue (retina) at the back of the eye (see adjacent picture) gets affected. Uncontrolled hypertension causes the blood vessels in the retina to start thickening therefore making them more narrow. This restricts the blood flow to the retina ma king it swollen and sometimes causing eye strokes (vessel occlusion) in the eye. This can also cause vision minor or major vision problems depending on the severity. This is called Hypertensive Retinopathy. In the more severe and dangerous form, it is called Malignant Hypertension and at this stage it can cause profound blurring vision or even sudden loss of vision.
SYMPTOMS IN THE EYE
When eye symptoms occur, it generally means the hypertension is advanced and already at a late stage. The symptoms may include blurring vision, double vision, headaches or even sudden loss of vision.
SIGNS LOOKED FOR IN THE EYE BY THE DOCTOR
Hypertensive Retinopathy may be evaluated on a scale of 1 to 4. On the lower end of the scale, there may not be any symptoms yet. In the more severe stage of grade 4, the eyes have a swollen nerve (optic nerve) resulting in serious profound vision problems. This late stage is dangerous and indicates uncontrolled hypertension and has a high risk of generalised systemic complications including death.
Prompt diagnosis of hypertensive retinopathy is important in order to avoid visual and systemic morbidity such as heart disease, strokes and renal disease.
The eye certainly gives a grand-stand view of the often hidden systemic problems since it is the only organ where a doctor can visualise blood vessels without having to open up the body. If you suffer from hypertension, it is advisable to get your eyes checked at least once a year before any eye symptoms appear.