Category B - full version without watermark 720x576 (check terms and conditions at www.teledesign.de) The version with watermark is for free to embed A cataract is a painless clouding of the lens of the eye. You generally develop cataracts over a long period of time, leading to a gradual worsening of your eyesight. They can eventually lead to blindness if left untreated. Surgical removal of your cataract is the only way to restore or maintain your vision. This involves replacing your cloudy lens with an artificial one. The most common technique is called phacoemulsification. This is typically performed under local anaesthetic. This completely blocks the feeling from the eye area and you will stay awake during the operation. In cataract surgery, the cloudy natural lens must be removed from the eye. After that, in most cases a permanent intraocular lens (IOL) implant replaces the natural lens to restore focusing power.