BEIJING — A surgeon in China says he has built an extra nose out of a man’s rib cartilage and implanted it under the skin of his forehead to prepare for a transplant in what may be the first operation of its kind.

Surgeon Guo Zhihui at Fujian Medical University Union Hospital in China’s southeastern province of Fujian spent nine months cultivating the graft for a 22-year-old man whose nose was damaged.

The striking images of the implant — with the nostril section facing diagonally upward on the left side of the man’s forehead — drew widespread publicity after they began to circulate in Chinese media. Guo plans to cut the nose from the forehead while leaving a section of skin connected, and then rotate and graft it into position in a later operation.

“We were just interested in helping the man and did not expect it would stir up this much attention,” Guo said in an interview.

Surgeons previously have used cartilage to help rebuild noses in their proper position and are experimenting with growing new ones from stem cells on other parts of the body, such as a forearm. This was the first known case of building a nose on a forehead.

Alexander Seifalian, a professor of nanotechnology and regenerative medicine at University College London who has worked on transplants using stem cells, said implanting the nose graft in the forehead makes sense because the skin there has the same “structure and texture” as that of a nose.

However, he said it was unclear why the Chinese team built the nose on the forehead rather than in its proper position. “They could have made the nose and just put it on the nose,” he said.

The patient lost part of his nose in an accident in 2012, and an infection later ate away much of his nose cartilage, Guo said.