Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=220415
Story Retrieval Date: 3/11/2014 2:27:39 AM CST
Photo courtesy of Reigh LeBlanc
An MRI scan of the human brain with an arrow pointing to the thalamus. New research shows the importance of tracking shrinkage in the thalamus to assist in diagnosing MS.
Researchers find link between glandular shrinkage, MS
Shrinkage of the thalamus gland was the most reliable predictor of which patients would develop definitive multiple sclerosis, researchers reported Tuesday.
“The point is we looked at lesions,” said Dr. Robert Zivadinov, director of the University of Buffalo Neuroimaging Analysis Center. “Very surprisingly, it resulted that thalamic atrophy was more predictive than the appearance and number of new lesions that appeared.”
In the new study, published in the journal Radiology, researchers tested 216 patients diagnosed with clinically isolated syndrome over two years, following up every six months. Using magnetic resonance imaging measurements, they found that decreasing thalamic volume was common with the 92 patients, or nearly 45 percent, that developed clinically definite MS.
MS is a potentially debilitating disease where the body’s immune system eats away at myelin, or the fatty substance that forms a tissue protecting nerves. According to the National Multiple Sclerosis Society, an estimated 2.1 million people are affected with MS worldwide. The clinically isolated syndrome has been described as a first neurological episode of MS caused by inflammation or demyelination, in one or more spots of the central nervous system.
The thalamus is part of the grey matter of the brain that acts as a point for processing and cognition. White matter, which acts as a communication coordinator between regions of the brain, has long been considered the primary area for disease in MS.
“The fact that thalamic atrophy was more predictive is going to shape our research in the future clinical trials,” Zivadinov said.
He said most of the current MS treatments can inhibit lesions, but they need to understand further how patients evolve in treatment in respect to the shrinking thalamus. He said they are already working on double-blind randomized trials testing how the gland’s shrinkage evolves in treatment.
“We need to apply this biomarker and see if this therapy can change thalamic atrophy over time,” he said.
Dr. Avertano Noronha, a neurologist at the University of Chicago, who was not involved in the study, said that the finding confirms the need to inspect the grey matter more carefully while still examining white matter.
“There is no surprise that in general over time, there is atrophy in the ventricles that contain the cells of spinal fluid that get bigger as the brain is shrinking,” he said.
Noronha said the study, “tells us it is not only there, but it’s also in the midline.”
Nicholas LaRocca, former neurology professor at Einstein Medical Center and vice president of healthcare delivery and policy research at the National MS Society in New York, said there has been increased attention to the relationship between regions in the brain in diagnosing MS.
“I think what it’s led to is an understanding of the fact that MS is much more complex than just lesions here and there,” he said, “and MS to some extent is doing something to overall organization and functioning of the brain even without appearance of lesions.”
LaRocca, who also was not involved in the study, said additional information will help future treatment plans for patients showing potential signs of MS.
“The more we can understand what the trajectory is of this pre-MS condition, the more that adds to the ability of doctor and patient to make some kind of an educated decision,” he said.
Noronha said as radiologists get this technology, the finding will add one more thing to look for.
“Imaging is increasingly important in MS,” he said, “and this will make a point for radiologists to really look at this.”
Zivadinov said researchers must determine how to apply this knowledge to a clinical regime, noting that radiologists do not have the software his team used to directly measure the thalamus in real time.
Going forward, he hopes to uncover the processes that lead to thalamic loss.
“Regarding the part of physiology and where is the damage in this thalamus coming from- we don’t know that,” Zivadinov said. “It’s something we’re looking for.”