Researchers at MIT have found a way to use smartphones and a device known as Catra to help detect cataracts. Cataract, the clouding of the eye's lens, is the world’s leading cause of preventable blindness. About 285 million people are visually impaired worldwide and 90% of the world's visually impaired people live in developing countries where access to eye care is limited or non-existent. Developed by Media Lab Camera Culture group director Ramesh Raskar and colleagues, the Catra system is made of off-the-shelf components. It is being tested in India at the LV Prasad Eye Institute, one of Seva's partners. (For English subtitles for the following video, click on the red CC at the bottom.) Users have to peer through an eyepiece that slides onto a smartphone or other smart devices such as an iPod Touch, and view lines displayed on the screen. When the lines appear cloudy, the user has to press a button to get the device to scan the lens of the eye to create a map of the areas that appear cloudy because of proteins clumping together. Catra produces a diagnosis of cataracts in minutes by identifying the position, size, shape and density of the clouds. It's been tested on 22 people. According to reports, the system even identified one case of cataract that had not been picked up in an eye test at an ophthalmology clinic a few months ago. Catra is expected to give a boost to early cataract diagnosis in developing countries where few people have access to the expensive slit lamps and clinicians used to diagnose the disorder. Earlier detection of cataracts gets better results after surgery. Early cataract onset is difficult to diagnose. This is a device for measuring cataracts, which is highly portable and collects quantifiable data to help tackle a global health problem. According to recent news reports, several research and local practicing ophthalmologists have been in collaboration with this project and are enthusiastic about its unique outcomes.