It's been harder for smaller hospitals in Ontario and Quebec to get medical isotopes. (CBC)

Smaller hospitals in Ontario and Quebec continue to experience significant disruptions due to the shortage of medical isotopes, the special adviser to federal Health Minister Leona Aglukkaq said Friday.

At an emergency meeting of the natural resources committee on the production of medical isotopes, Dr. Sandy McEwan said he is trying to understand the regional disparity, its cause, and what can be done to help.

Western Canada seems to be coping better with the shortage, McEwan said.

However, he called the situation for patients a "great concern."

More reliable estimates of isotope supplies are now available in weekly bulletins so hospitals can plan and book appointments, but the length of the shutdown means the alternatives are clearly not sustainable over the long term, he said.

Last week, Atomic Energy of Canada Ltd. announced the aging National Research Universal, or NRU, reactor at Chalk River, Ont. won't be able to produce medical isotopes until at least next spring. The reactor was shut down in May, leading to a worldwide shortage of isotopes used in diagnostic imaging for cancer and cardiac patients and some cancer treatments.

Reactor repair timeline

"I want to state unequivocally our belief that the NRU can be repaired and is indeed well worth repairing," AECL's president and chief executive officer Hugh MacDiarmid told the parliamentary committee.

"We are confident that we can return this reactor to service in the first quarter of 2010," he said.

Natural Resources Minister Lisa Raitt has been clear that nothing else at AECL is to take precedence and that resources should be deployed on a 24/7 basis where possible, and that is happening, MacDiarmid said.

Bill Pilkington, senior vice-president and chief nuclear officer of AECL, said inspections showed the number of sites requiring repairs has increased to nine from one initially and then five.

The nine sites are in a band around the corroded base of the vessel, but they are difficult to access, he said. New tools need to be crafted to automatically make the repairs in a radioactive environment, he said.

Isotope alternatives

Robert Atcher, president of the International Society of Nuclear Medicine, told the panel that alternative isotopes for imaging present four problems in some cases:

• Higher radiation doses.
• Lower accuracy (for example, the alternative isotope thallium 201 provides poorer images of obese cardiac patients than technetium-99 from NRU).
• Increased costs.
• More-invasive procedures.

Pediatricians have also expressed concerns about using higher doses of radiation for their patients, Atcher said.

McEwan said sodium fluoride isotopes have been approved for use in PET bone scans in Canada. But doctors in the U.S. have not yet received permission to charge Medicare for the alternative way of checking whether cancer has spread to the bone in lung, breast and prostate cancer patients, Atcher said.

Coviden, which processes isotopes for imaging procedures, said it expects to begin receiving material from the Petten reactor in the Netherlands starting this weekend, according to a letter to hospital clients dated August 18 and posted on the U.S. Food and Drug Administration website on Thursday.

The worldwide shortage was exacerbated when both NRU and Petten were offline, which could happen again for four to six months starting in March 2010.