Dr. Xiaoping Ren (File photo)

A Chinese surgeon leading the world’s first human head transplant carried out on a corpse in China has defended the controversial operation.

The procedure was carried out by a team led by Dr. Xiaoping Ren from Harbin Medical University in northeastern China, according to Italian professor Sergio Canavero.

“During the 18-hour operation, experts successfully reconnected the spine, nerves, and blood vessels of a severed head,” Ren said, adding that a full report about his team’s procedure and a timeframe for the live transplant are expected within the next few days.

“There has never been such a procedure in surgery. We completed the design of the operation, including how to cut and how to deal with the nerves, blood vessels, and muscles. Those are our achievements,” Ren said.

The test run helped the doctors explore various technical options with the surgery and ways to repair tissue, the doctor added.

But critics in the medical community say it is premature to perform such a transplant on humans and a test run on cadavers is no guarantee of success.

Hu Yongsheng, a professor at Xuanwu Hospital Capital Medical University in Beijing, said the operation cannot be technically called surgery, because Ren’s operation on a corpse was about gaining an understanding of anatomy.

Hu suggests that scientists fully test the procedure on animals before carrying out such a surgery on a living human. “Head transplants might eventually become a reality, but not right now.”

The operation can be regarded as an early-stage practice of a real experimental head transplant, Hu said. “It is the first step forward toward a very long distance.”

Ren defended the surgery by saying that all medical progress is achieved amid debates, citing that similar attacks had been leveled against pioneering kidney transplants more than 60 years ago.

“When something new emerges, we should regulate and discuss it, but not to stop it, because history has proven that new things are unstoppable,” Ren said.