Key Points
- A team of researchers found that echoing soundwaves, captured as acoustic emissions signals generated by circulating microbubbles, are a reliable measurement to predict successful blood-brain barrier opening.
- Their work will help standardize treatments across medical centers and allow physicians to compare clinical outcomes and other treatment effects.
Acoustic Emissions Dose and Spatial Control of Blood-Brain Barrier Opening with Focused Ultrasound
A collaborative team of researchers from the University of Maryland School of Medicine (UMSOM), Mass General Brigham, and other academic institutions recently published their recommendations for defining a dose of microbubble-enhanced transcranial focused ultrasound (MB-FUS) for safe and reversible blood-brain barrier opening (BBBO).
These experts determined that the acoustic emissions dose (AED) can be used to monitor the procedure and its effects.
The team analyzed just under 1,000 MB-FUS sonications performed in 23 patients with brain tumors under a closed feedback loop power scheme. In their analysis, they considered the many patient-specific (e.g., tumor size and location, skull density ratio), operator-adjusted (e.g., AE and MB dose, target, power, duration), and device-related (e.g., the closed feedback loop controller, active elements, duty cycle) factors that lead to successful BBBO. All of the procedures were performed with Insightec’s transcranial Exablate system, which has a multi-element transducer with integrated acoustic emissions detectors and operates under MRI guidance.
The group found AED to be an independent, continuous, and robust predictor of BBBO and used the data to determine an optimal dynamic dose range for successful MB-FUS BBBO.
“Acoustic emissions monitoring and acoustic emissions-derived dosing regimens offer an opportunity for a unifying concept in focused ultrasound,” said Graeme Woodworth, MD, Professor and Chair of Neurosurgery at UMSOM in their press release. “The data and analysis provided in this study serve to advance this methodological paradigm and the focused ultrasound field.”
As an adopted universal metric, AED will help standardize treatments across medical centers and allow physicians to compare clinical outcomes and other treatment effects. Monitoring and capturing AED data will allow comparison between clinical trials and between various focused ultrasound devices used for brain treatments. It may also be used for future regulatory standards.
This study was funded by Insightec and the Focused Ultrasound Foundation. The data were obtained from the multi-site BT008NA clinical trial, which was registered on ClinicalTrials.gov as NCT03551249 and NCT03616860.
See Device (Open Source)
See the University of Maryland Press Release
See the Mass General Brigham Press Release
See Media Coverage in Newswise, Medical Xpress, and Applied Radiology