Non-Invasive Targeted Peripheral Nerve Ablation Using 3D MR Neurography and MRI-Guided High-Intensity Focused...

Area of Science:

• Medical Imaging
• Neurosurgery
• Ultrasound Technology

Background:

• Ultrasound-guided high-intensity focused ultrasound (HIFU) shows promise for neuropathic pain but has guidance limitations.
• Magnetic resonance (MR)-imaging guidance offers potential solutions for improved treatment accuracy and monitoring.

Purpose of the Study:

• To assess the feasibility of using 3D MR neurography with a clinical MR-HIFU system for peripheral nerve ablation.
• To evaluate MR neurography's effectiveness in identifying and guiding ablation of target nerves.

Main Methods:

• Volumetric MR-HIFU was employed to create lesions in peripheral nerves of pigs.
• Diffusion-prep MR neurography and T1-weighted imaging were used for target identification, treatment planning, and post-treatment assessment.
• Histological analysis confirmed ablation site and extent.

Main Results:

• MR neurography accurately identified target peripheral nerves for MR-HIFU ablation.
• Ablation was achieved with single focused ultrasound exposures, reaching peak temperatures of 60.3–85.7°C.
• Lesion dimensions measured via MR neurography correlated well with other imaging modalities and gross pathology, with histology confirming localized nerve damage.

Conclusions:

• MR-HIFU is a feasible technique for targeted peripheral nerve ablation.
• Diffusion-prep 3D MR neurography shows potential for guiding nerve-targeting or avoidance therapies and verifying thermal lesions without contrast agents.