The upper row of images shows blood samples through a traditional microscope. The bottom row shows the same samples imaged on a smartphone.

Courtesy of Sebastian Wachsmann-Hogiu and colleagues hide caption

itoggle caption Courtesy of Sebastian Wachsmann-Hogiu and colleagues

A silicone gel implant (left) and a saline gel implant. The FDA agreed to let implants return to the market in 2006, but stipulated that manufacturers track long-term side effects. Spencer Platt/Getty Images hide caption

itoggle caption Spencer Platt/Getty Images

Many people with sleep apnea wear a CPAP machine mask in bed to help them breathe. Amy Walters/iStockphoto.com hide caption

itoggle caption Amy Walters/iStockphoto.com

The regulation of medical devices bears a passing resemblance to this giant version of the Rube Goldberg-style game Mouse Trap. Bill Ward/Flickr hide caption

itoggle caption Bill Ward/Flickr

Doctors perform a kidney transplant operation in Spain in 2010. One in three people with kidney failure has antibodies that make it hard to receive a transplant, but a new treatment can get rid of them prior to transplant. Xurxo Lobato/Cover/Getty Images hide caption

itoggle caption Xurxo Lobato/Cover/Getty Images