Key Points
- A recent report shows focused ultrasound being safely used on a patient who had previously been implanted with DBS leads.
- The patient successfully underwent the procedure to treat their movement disorder.
It has been postulated that performing focused ultrasound in patients with indwelling metallic devices and electrodes may be risky. The focused ultrasound beam may be deflected and thus not reach the desired target, potentially harming surrounding tissues – or it may heat the DBS device causing uncontrolled heating. However, in Korea, a focused ultrasound pioneer recently published a report showing how he and his team safely used the technology to perform a pallidothalamic tractotomy (PTT) in a patient with DBS leads still implanted in the globus pallidus internus (GPi) region of the brain.
Jin Woo Chang, MD, PhD, a professor of neurosurgery at Korea University Anam Hospital in Seoul, used MR-guided focused ultrasound to perform the high-intensity PTT. The case study has been published in the journal Brain Stimulation.
Dr. Chang performed the high-intensity PTT with the Insightec Exablate Neuro focused ultrasound system in a 69-year-old man who was previously unsuccessfully treated with GPi DBS. The patient had a three-year history of uncontrolled right-sided hemichorea, a movement disorder that produces involuntary muscle spasms on one side of the body.
In most cases, surgeons remove any pre-existing DBS hardware before proceeding with focused ultrasound treatment. In this case, the removal of the hardware created a concern, so the decision was made to perform focused ultrasound with the DBS hardware in place.
“Our concern was that the sonication used for high-intensity focused ultrasound could potentially heat the implanted lead of DBS device,” said Dr. Chang. “However, focused ultrasound is capable of delivering precise and accurate sonication, with targeting accuracy at the sub-millimeter level, so we felt confident in proceeding.”
The authors concluded that using high-intensity focused ultrasound for PTT was a viable treatment option when GPi-DBS fails.
See Brain Stimulation (Open Access)