My PD Story

Utilizing Targeted Ultrasound Waves to Help Alleviate Freezing of Gait in Parkinson’s

Robert Chen, MA, MB BChir, MSc, FRCPC, of Toronto Western Hospital and recipient of a Parkinson’s Foundation Impact Award, will be exploring how using ultrasound waves targeted at specific regions of the brain might alleviate movement impairments in people with Parkinson’s disease (PD).

Dr. Chen and his team are interested in treating the common PD symptom known as freezing of gait — when people with Parkinson’s are suddenly unable to move their feet, no matter how hard they try. While freezing episodes often only last seconds, unexpected freezing of gait episodes can lead to serious falls and injuries. Current PD medications do not address freezing of gait, driving further research into alternative treatments.

What is freezing of gait?
Some people with Parkinson’s may experience “freezing” episodes —the temporary, involuntary inability to move. Usually, freezing lasts a few seconds, but it is one of the more frustrating and dangerous symptoms of PD as it can lead to falls.

Recent studies have found that freezing of gait may be related to overactivity in the cerebellum, a structure deep within the brain responsible for posture, balance and coordination of movement. Transcranial magnetic stimulation (TMS), a non-invasive treatment involving the activation of neurons using magnetic pulses, has shown success in managing similar movement symptoms of PD. However, TMS is unable to reach the cerebellum effectively, limiting its use in treating freezing of gait.

Where TMS falls short, Dr. Chen will be investigating if transcranial focused ultrasound (TUS) can go the distance. TUS uses ultrasound acoustic waves to stimulate neurons in a manner similar to TMS; however, ultrasound waves can penetrate deeper into the brain than magnetic waves, making TUS an ideal candidate for reaching the cerebellum and treating freezing of gait in Parkinson’s.

With help from the Toronto Western Hospital Movement Disorders Clinic, a Parkinson’s Foundation Center of Excellence, Dr. Chen will be enrolling 25 people with Parkinson’s who experience freezing of gait for his study. These participants will undergo MRI and CT scans of their brain before and after undergoing either TUS or a placebo treatment (where the ultrasound waves will not be directed to the brain), allowing Dr. Chen to calculate and measure the effects of ultrasound stimulation on the area of the brain related to freezing of gait. The participants’ freezing of gait symptoms will be assessed before and after treatment as well, determining whether TUS can help alleviate freezing of gait in people with PD.

Speaking about his Parkinson’s Foundation Impact Award, Dr. Chen said, “The support from the Parkinson community is strong encouragement for me to be fully engaged in Parkinson’s research to improve the lives of people with Parkinson's disease. This research will increase our understanding of the pathophysiology of Parkinson's disease, particularly freezing of gait, which is disabling and is resistant to current treatments. This will lay the foundation for the development of transcranial ultrasound stimulation as new, non-invasive treatment for Parkinson's disease.”