Dr. Ming Wang has taken his ophthalmology expertise to China, where he's bought an ownership stake in the country's largest private eye hospital system and trained thousands of eye surgeons.

Wang, who emigrated from China 24 years ago, began taking a more active role in the 1.3 billion-person country after starting the Wang Vision Institute in 2002. He believed the rapid adoption of cellphones and automobiles would translate into potential for eye surgery locations.

"China's economic growth is unprecedented. Never before in world history has there been such rapid economic growth with both speed and amplitude with such a big population," Wang says. "When I came to the U.S. years ago, 90 percent of the vehicles on the street were bicycles. When I went back in April, 90 percent of the vehicles were cars."