Cape Town: A musician from South Africa had a tumour in his brain, so doctors opened a hole in his skull to remove it. But they had a crucial request: He must play his acoustic guitar during the surgery.

The musician, Musa Manzini, a jazz bassist, was awake when the doctors performed the surgery last week, and video footage from the local media site News24 shows him strumming an acoustic guitar slowly as they operated.

The technique, known as "awake craniotomy", allows doctors to operate on delicate areas of the brain — like the right frontal lobe, the site of Manzini's tumour — without causing damage. Presumably, had he hit a wrong note, it would have been an immediate signal for the surgeons to probe elsewhere.

"It can be very difficult to tell the difference between the tumour and normal brain tissue," said Dr Basil Enicker, a specialist neurosurgeon who led the operation at Inkosi Albert Luthuli Central Hospital. "Once you're near a critical area, you can pick it up early, because he will tell you."