Tremor is one of the most common and obvious Parkinson’s disease symptoms. Parkinson’s tremor is typically a resting tremor. It usually starts in the fingers, hand or foot on one side of the body. As the disease progresses, it affects both sides of the body and can also involve the jaw, chin or mouth.
Parkinson’s tremor tends to be a slow, rhythmic shake that occurs when the body part is at rest. This differentiates it from other types of tremor, such as benign familial tremor or essential tremor. Other tremors are usually action or intention tremors. This means they are less noticeable at rest but increase with actions, such as taking a drink or raising a utensil to your mouth.
Most people with Parkinson’s tremor do not have much disability with it. It tends to decrease with actions, so it doesn’t usually interfere with daily activities. However, it can be very annoying and embarrassing. For many people, it negatively affects quality of life. And it can be severe for some people, making activities difficult. It is also often hard to treat. But one recent advance in Parkinson’s treatment has expanded the options available to people with tremor-dominant disease.
For many years, medications were the only option for treating Parkinson’s tremors. Levodopa is the main drug for treating movement problems in Parkinson’s. But tremor may or may not respond to it. Anticholinergic drugs often do a better job of controlling tremor. But they have significant side effects that can be problematic, including dry mouth, blurry vision, confusion, urinary retention, and constipation. Memory problems and hallucinations can occur as well. So, medications may or may not be the answer.
In the late 1990s, an alternative to medications became available. The FDA (Food and Drug Administration) approved deep brain stimulation (DBS) for the treatment of Parkinson’s tremor. DBS works in the brain a bit like a pacemaker for the heart. It involves placing an electrode in a specific area in the brain. It also requires a pulse generator to send electrical signals to the electrode. Doctors place the pulse generator under the collarbone or in the abdomen. The electrical pulses cancel out the faulty signals in the brain that cause the tremor.
DBP is an option for people whose tremor does not adequately respond to drugs. It now has approval for other motor symptoms in advanced disease and early Parkinson’s, as well, when medicines are not enough.
DBS can be an effective option, but it is very invasive, requiring a small drill hole in the skull to place the electrode and an incision in the chest or belly area to place the pulse generator. It carries risks, such as infection, stroke, bleeding and seizures. People may also experience speech and thinking difficulties afterwards. So, researchers continued to look for successful treatment alternatives.
December 2018 brought another leap forward in Parkinson’s tremor treatment. The FDA approved Exablate Neuro for the treatment of tremor-dominant Parkinson’s. Exablate Neuro is a focused ultrasound device.
Ultrasound technology is noninvasive and uses sound wave energy. It’s a common form of imaging technology. But it can also be therapeutic when it destroys diseased tissue. A single ultrasound beam does not have enough energy to damage tissues. However, concentrating multiple ultrasound waves produces a beam that can destroy small areas of tissue. Another name for this technology is high-intensity focused ultrasound (HIFS).
To treat Parkinson’s tremor, HIFS targets a specific area in the brain from outside the skull. Doctors use MRI (magnetic resonance imaging) to precisely locate the area and aim the HIFS beam. The concentrated beam burns a lesion in the area, which interrupts the circuits causing tremor. It’s able to do this without creating a hole in the skull or damaging surrounding healthy brain tissue. This allows for a quicker recovery and fewer side effects. It’s an effective noninvasive alternative to DBS. However, insurance companies currently do not cover the procedure.
If you are interested in learning more, talk with your doctor to find out if you are a candidate. There are also ongoing clinical trials looking at HIFS to treat other Parkinson’s symptoms, such as slowness and stiffness.