Multiple Sclerosis: The Thalamus Moves into the Spotlight


Photo: Thalamus

This 3D view shows a composite of the thalamus of healthy controls (outlined in red) and MS patients (magenta). The whole thalamus is generally smaller in MS due to atrophy, and is also shifted (as seen in blue) slightly;
© UB

A growing body of research by multiple sclerosis (MS) investigators at the University at Buffalo (UB) and international partners is providing powerful new evidence that the brain’s gray matter reflects important changes in the disease that could allow clinicians to diagnose earlier and to better monitor and predict how the disease will progress.

Over the past three years, the UB researchers and their partners around the world, supported by an active fellowship program at UB’s Buffalo Neuroimaging Analysis Center (BNAC) and given presentations demonstrating that the thalamus region, in particular, is key to a host of issues involving MS.

“The thalamus is providing us with a new window on MS,” says Doctor Robert Zivadinov. “In our recent studies, we have used large datasets to investigate the evolution of atrophy of the thalamus and its association with clinical impairment in MS, starting with the earliest stages of the disease. The location of the thalamus in the brain, its unique function and its vulnerability to changes wrought by the disease make the thalamus a critical barometer of the damage that MS causes to the brain.”

The study found that atrophy of the thalamus, determined with MRI, can help identify which patients with clinically isolated syndrome (CIS), a patient’s first episode of MS, are at risk for developing clinically definite MS. Such a tool would be immensely helpful to clinicians, Zivadinov notes.

“This study, which included more than 200 patients, shows that thalamic atrophy is one of the most important predictors of clinically definite MS,” says Doctor Dana Horakova, the principal investigator at the Charles University in Prague.

“Therefore, based on these findings, we think MRI should be used to determine which patients are at highest risk for a second attack,” explains Zivadinov.

MS is traditionally viewed as a disease of the brain’s white matter, in which myelin, the fatty material surrounding neurons that allows them to signal effectively, is gradually destroyed. The UB researchers are now revealing how the thalamus and other parts of the brain’s gray matter, play a key role as well.

Central to a wide variety of neurologic functions, the thalamus is involved in motor and sensory function, the regulation of sleep and wakefulness, memory, emotion, consciousness, awareness and attention. It functions as a kind of relay center in the brain, taking in sensory information and sending it to the cerebral cortex; it also processes information coming from the cortex.

“In another study, we found that cognitive dysfunction appears early in the course of MS and that thalamic atrophy plays a central role in predicting cognitive deterioration over the long-term,” says Zivadinov. The findings reveal that atrophy of the thalamus, determined through routine magnetic resonance imaging (MRI), can be an important tool in detecting, evaluating and predicting the course of MS in children and adults; it also may become a valuable method of evaluating new MS treatments.; Source: University at Buffalo