Novel Mri Techniques May Have Better Outcomes in Treating Tremors Associated to Parkinson's Disease

A study published today in the journal Brain discussed recently developed MRI techniques designed to precisely target a small area in the brain's thalamus involved in movement. Using these images, physicians can use high-intensity focused ultrasound (HIFU) to remove or burn away the problem tissue, which causes the tremors.

Surgery will no longer be needed for this procedure and has a lesser risk of adverse effects, according to the first author of the study Bhavya R. Shah, M.D., an assistant professor of radiology and neurological surgery at U.T. Southwestern's Peter O'Donnell Jr. Brain Institute.

"The benefit for patients is that we will be better able to target the brain structures that we want. And because we're not hitting the wrong target, we'll have fewer adverse effects," Shah says.

The Food and Drug Administration already approves the procedure, and the U.T. Southwestern plans to start on using it in treating patients on the opening of the Neuro High-Intensity Focused Ultrasound Program this fall.

Adverse Effects of Inaccurate Treatment of Tremors in Parkinson's Disease

Previous treatments of Parkinson's disease could have adverse effects which include problems walking or slurring words. According to Dr. Shah, these could be temporary, but about 15% to 20% of the cases can become permanent.

Furthermore, the National Institutes of Health said that essential tremor affects up to 10 million Americans, while Parkinson's disease impacts 1 million people in the U.S.

The two neurologic diseases are believed to have genetic links, and the typical treatment for the involuntary tremors exhibited by people with these disorders is medication. But the new study revealed that about 30% of the patients do not respond well to the drugs.

Neurosurgeons used to employ the deep brain stimulation procedure during the late 1990s. They open the patient's skull to permanently implant metal electrodes that could then be activated using a battery pack.

Then just a decade ago, scientists were able to develop a new MRI-guided procedure that utilizes high-intensity ultrasound waves to heat and eradicate a small part of the thalamus linked to the neurological disorders.

It is currently approved to use on patients, and they are awake during the procedure since it does not require to open the skulls.

"No cuts. No anesthesia. No implanted devices' says, Dr Shah.

Three New MRI Techniques

Traditionally, doctors rely on the brain from cadavers to help them locate the correct location of the tissue causing the tremors. A small error in locating can lead to damage in the surrounding tissue, Dr. Shah said.

According to EurekAlert!, the new study discusses three newly refined MRI techniques in locating the target tissue. The commonly studied method is the diffusion tractography which creates precise brain images by taking into account the natural water movement within tissues.

The other method involves the quantitative susceptibility mapping that created contrast in the image by detecting distortions in the magnetic field because of the substances like iron and blood.

Moreover, it also involves fast gray matter acquisition T.I. Inversion recovery which turns the brain's white matter dark and its gray matter white to provide greater detail in the gray matter.

To test the diffusion tractography method in patients, Dr. Shah and his team plan to participate in a multicenter clinical trial along with collaborators at the Mayo Clinic in Rochester, Minnesota.