What are Cataracts?

9 September 2019

A cataract is a medical condition that affects most people sooner or later. It is the most common eye disease and part of the normal aging process. After the age of 50, it is quite probable that the human eye starts to develop some form of this ocular disease. The word cataract is derived from the Latin cataracta, meaning ‘waterfall’ and from the Ancient Greek καταρράκτης (katarrhaktēs), which means ‘down-rushing’. Like water rapidly rushing turns white, it may be a metaphorical term to describe the effect running time has on the whitening of a lens with advanced cataract progression.

Impaired
Healthy

Vision impaired by cataract
Healthy vision

Cataract causes

Cataracts are an eye disorder that occurs typically with increasing age. The natural lens of the eye, called also crystalline lens is mostly made of water and protein. Due to a change in that protein structure over time, the natural lens becomes increasingly cloudy – gradually causing the main symptoms of cataracts.

According to the latest assessment of the World Health Organization (WHO):

Cataracts are responsible for 51% of world blindness and remains the leading cause of blindness.
This represents about 20 million people.
Many people over the age of 50 have some form of this eye disorder.¹

At an early stage of cataracts, the crystalline lens starts to become cloudy causing slightly blurred vision. The more the cataract advances, the worse the quality of the image projected onto the retina becomes. Untreated, it may lead to blindness.

Symptoms

Signs to detect a cataract

It starts out slowly with little influence on your sight. The first sign of cataracts may be when you notice that your vision is a little blurry. It may feel like looking through a cloudy piece of glass or a foggy layer on a window. To detect cataracts at an early stage, it is important to know the most common symptoms.

Common symptoms of cataracts include: