Friday, December 12, 2008

Brain scans may detect early MS

From The Globe & Mail in Toronto:

Brain scanning technology is now so sophisticated that neurologists can detect what appear to be early signs of multiple sclerosis in perfectly healthy patients. And new research by University of California neurologist Darin Okuda has found that about one-third of these patients will go on to experience the disease within 5 ½ years.

"We're capturing MS at such an early time frame now, we're capturing it before symptoms occur," says Dr. Okuda, who followed 44 patients with abnormal magnetic resonance imaging scans that suggested MS.

But because it's too early to know which patients will develop MS, an auto-immune disease that can cause reduced mobility, speech and co-ordination, nerve damage and vision problems, Dr. Okuda's findings have sparked a debate about exactly when it is appropriate to diagnose MS.

Do people have MS if their brains say they do but they have none of the common physical symptoms, such as muscle weakness and vision problems?

Should doctors tell them MS may be on the horizon?

Dr. Okuda's subjects had undergone MRIs due to complaints about symptoms such as headaches or head trauma. Their scans showed signs of the kinds of abnormalities associated with MS - such as an increasing number of lesions in the white matter of the brain - that could not be explained by other diseases or causes.

In addition to the patients who went on to develop symptoms, a further 30 per cent of patients' follow-up scans showed a progression of MS-style abnormalities over time, unaccompanied by symptoms.

Dr. Okuda, who continues to follow these and other patients, says he hopes more research will determine why some patients develop MS - and whether early treatment is possible. He proposes a new classification to describe patients with MRI-only signs of MS, called Radiologically Isolated Syndrome.

Some neurologists are wary of Dr. Okuda's approach. "For now, it is best to recall the wise advice that we treat the patient, not the MRI," Dennis Bourdette of Oregon Health and Science University writes in an editorial that accompanies the study published in the journal Neurology.

The research could have major implications for Canadians, who have one of the highest rates of MS in the world. An estimated 55,000 to 75,000 have the disease and about 1,000 new cases are diagnosed each year, according to the MS Society of Canada.

Paul O'Connor, the director of the MS program at Toronto's St. Michael's Hospital and a professor of neurology at University of Toronto, says that while he sees value in defining a new population of potential MS sufferers, telling patients they may have MS is problematic.

"Labelling people with MS has negative consequences for them in terms of employability, insurance and marriageability," he says. "Most neurologists would not label these patients with MS or treat a patient who had never had symptoms of the disease."

Dr. Okuda says these ethical concerns may come to be outweighed by a patient's desire to address a potential health problem. Currently, he does not recommend treatment for those without symptoms.

"...If it were me and I was having more MRI changes over time, I would still want something done."