A Fully Electronically Steerable Therapeutic Ultrasound Phased Array With MR-Guidance

Area of Science:

• Medical Imaging and Ultrasound Technology
• Neurosurgery and Interventional Radiology
• Biomedical Engineering

Background:

• MRI-guided focused ultrasound (FUS) offers a promising non-invasive therapeutic approach.
• Existing FUS systems may have limitations in steering range and near-field heating.
• Uterine fibroids are a common condition often requiring invasive treatment.

Purpose of the Study:

• To introduce a novel MRI-guided FUS device with full electronic steering and minimal near-field heating.
• To evaluate the feasibility and safety of this new FUS device in pre-clinical and clinical settings.
• To assess the efficacy of the device for treating uterine fibroids.

Main Methods:

• A flat, 4096-element, fully steerable FUS phased array compatible with MR scanners was designed and manufactured.
• Pre-clinical studies involved testing focus accuracy, ablation efficiency using MR thermometry, and near-field heating.
• A pilot clinical trial treated eleven patients with uterine fibroids.

Main Results:

• Pre-clinical experiments confirmed accurate targeting, efficient ablation at various angles, and no off-target heating.
• The pilot clinical study showed effective uterine fibroid ablation and significant symptom reduction.
• The device efficiently ablated large tissue volumes with minimal near-field heating, avoiding mechanical translation.

Conclusions:

• The developed MRI-guided FUS device offers high acoustic power and 3D electronic steering for large-volume ablations.
• This system presents a safe and efficient outpatient treatment option for uterine fibroids.
• The technology holds potential for treating other pelvic and abdominal tumors non-invasively.