In the past, cornea transplants relied solely on donation, making corneas is a scare resource. Scientists around the world have been looking for proper material to create a substitute for the human cornea. However, making an artificial cornea that has the identical intricate structure to a human cornea is very difficult.

　　After more than 10 years of effort, researchers in The Fourth Military Medical University have successfully made a biological cornea from that of a pig, which function's like the human cornea. Professor Jin Yan is the director of the school of organ engineering.

　　"A pig's organ structure is very close to that of a human's. But to use it, we must remove the pig's antigenicity and cells, while maintaining the useful collagenous fibers. This is the key to making a perfect cornea. It's also one of the most challenging technical difficulties."

　　Jin Yan says a few high-tech reagents are the final solution to this problem.

　　China's artificial biological cornea was put into clinical trials in 2010. One-hundred and fifteen patients from different hospitals in the country participated in the trial.

　　Zou Liuhe, a doctor at Beijing Tongren Hospital, says the trials proved successful.

　　"We see from observation that such cornea can help the recovery of ulcers. No rejection reaction was found between the two organs. Seventy percent of the replaced corneas are clear and safe to use in humans."

　　Zhang Mingchang, director of the ophthalmology department at Wuhan Union Hospital, says the clinical trial success of China's artificial biological cornea may bring big hopes for the visually impaired nation-wide.

　　"These artificial corneas solve the problem of material scarcity. We can use such products to perform operations in a timely manner. It especially benefits patients who are in the early stages of visual impairment--it gives us more options."

　　Figures show that more than five million people in China need cornea transplant operations. The number is growing by about 100,000 each year, but only 3,000 corneas were donated annually.