(Not Hamish) shows the condition he had.
"It has really boosted my confidence. It's made a dramatic difference. I'm really thrilled about it," Hamish said.
A competitive swimmer, he now plans to get into water polo next year.
Mr Moaveni said Hamish's loss of confidence and experience of teasing were common among people with a chest deformity. About one in 400 people are born with a deformity in the shape of their chest, most commonly a hollow, while in others it sticks out as a "pigeon chest".
The cause of the deformity, more common in males than females, is not known, but there is often a family history and it may be linked to connective tissue disorders. In the more severe cases, the lungs and heart can be affected, leaving the person short of breath on exertion.
Mr Moaveni estimated that in about a third of people with the condition it was severe enough to need surgical correction.
He has developed a new operation, called small incision sternoplasty, which uses a smaller incision - about 7cm long on average - and is less invasive than earlier procedures. The sternum - the breastbone - is cut and a wedge of bone removed to reangle the lower section of the bone. The ribs connect to the sternum through flexible cartilage, so the surface of the chest can be moved in or out, as needed.
A titanium plate - about 6cm long, 5mm wide and 3mm thick - is screwed on to the two parts of the severed sternum from the front. The sternum heals, but the plate is left in place permanently.
Mr Moaveni, who presented findings on use of the new technique to a surgeons' conference in Queenstown yesterday, said about 20 patients had had the procedure since 2011. None had experienced the return of their deformity and there were big improvements in exercise tolerance and self-image. On a scale of 1 to 10, where 10 was the worst, the average self-consciousness score was 7 to 9 before surgery. After surgery it had dropped to 1 to 2.
"The improvement in scores was quite dramatic."
The operation
• To correct severe chest deformities.
• The breastbone is cut.
• A wedge of bone is removed to reangle the breastbone.
• A narrow titanium plate is screwed on to the two sections of bone.