This cyclotron at Sherbrooke University Hospital produces radioactive fluorine used in bone scans. (Dr. Eric Turcotte)

A hospital in Quebec has found a way to ease the impact of the worldwide shortage of medical isotopes by resurrecting an old test that uses an isotope that doesn't require a nuclear reactor to produce it.

The shortage of medical isotopes was caused by a shutdown last month of the nuclear reactor at Chalk River, Ont., which normally produces 30 per cent of the world's stock. It's expected to be out of service for months.

Sherbrooke University Hospital produces a sodium fluoride isotope that can be used for bone scans, which make up 20 to 40 per cent of scans done in a day, according to Dr. Eric Turcotte.

Rather than using a nuclear reactor, radioactive fluorine is produced in a cyclotron and incorporated in a sterile solution as sodium fluoride. It's much cheaper, Turcotte said: It costs about $1 billion to build a reactor, but about $6 million to build a cyclotron facility.

A PET-CT scanner is used to trace the radioactive sodium fluoride. (Dr. Eric Turcotte)

The radioactive sodium fluoride is "not a new tracer. It was developed 40 years ago," Turcotte said. "But its use was stopped because at that moment it was very, very expensive."

Scans performed faster

Using it for bone scans has other advantages as well, he said. The images are more precise, and the test itself takes 45 minutes instead of four hours.

"The catch is you need a special machine (Positron emission tomographs and PETscanners) and permission from Health Canada to use the radioactive tracer," Turcotte said.

After the Chalk River shutdown in 2007, the hospital applied for permission to produce its own sodium fluoride isotopes.

There are 13 PETscans for producing images with the sodium fluoride isotope in Quebec, and Sherbrooke has two, Turcotte said.

"So we are helping many hospitals, such as Sainte-Justine Hospital [in Montreal] and the hospital in Rimouski, to get approved by Health-Canada to use sodium fluoride."

The hospital in Trois-Rivières also started using the alternative sodium fluoride isotope last week. It has already boosted the number of tests staff are able to do, despite the worldwide isotope shortage.