A cataract is a cloudy area in the [lens](../../../../amdb/samples/tissue/1/) of the eye that leads to a decrease in vision. <a title="Rakesh Ahuja, MD, CC BY-SA 3.0 &lt;http://creativecommons.org/licenses/by-sa/3.0/&gt;, via Wikimedia Commons" href="https://commons.wikimedia.org/wiki/File:Cataract_in_human_eye.png"><img width="512" alt="Cataract in human eye" src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Cataract_in_human_eye.png/512px-Cataract_in_human_eye.png"></a> From [Wikipedia](https://en.wikipedia.org/wiki/Cataract) under [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/) license.